WSL2-Linux-Kernel/drivers/net/virtio_net.c

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C
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/* A network driver using virtio.
*
* Copyright 2007 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
//#define DEBUG
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/module.h>
#include <linux/virtio.h>
#include <linux/virtio_net.h>
#include <linux/bpf.h>
bpf: add initial bpf tracepoints This work adds a number of tracepoints to paths that are either considered slow-path or exception-like states, where monitoring or inspecting them would be desirable. For bpf(2) syscall, tracepoints have been placed for main commands when they succeed. In XDP case, tracepoint is for exceptions, that is, f.e. on abnormal BPF program exit such as unknown or XDP_ABORTED return code, or when error occurs during XDP_TX action and the packet could not be forwarded. Both have been split into separate event headers, and can be further extended. Worst case, if they unexpectedly should get into our way in future, they can also removed [1]. Of course, these tracepoints (like any other) can be analyzed by eBPF itself, etc. Example output: # ./perf record -a -e bpf:* sleep 10 # ./perf script sock_example 6197 [005] 283.980322: bpf:bpf_map_create: map type=ARRAY ufd=4 key=4 val=8 max=256 flags=0 sock_example 6197 [005] 283.980721: bpf:bpf_prog_load: prog=a5ea8fa30ea6849c type=SOCKET_FILTER ufd=5 sock_example 6197 [005] 283.988423: bpf:bpf_prog_get_type: prog=a5ea8fa30ea6849c type=SOCKET_FILTER sock_example 6197 [005] 283.988443: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[06 00 00 00] val=[00 00 00 00 00 00 00 00] [...] sock_example 6197 [005] 288.990868: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[01 00 00 00] val=[14 00 00 00 00 00 00 00] swapper 0 [005] 289.338243: bpf:bpf_prog_put_rcu: prog=a5ea8fa30ea6849c type=SOCKET_FILTER [1] https://lwn.net/Articles/705270/ Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 04:28:18 +03:00
#include <linux/bpf_trace.h>
#include <linux/scatterlist.h>
#include <linux/if_vlan.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 11:04:11 +03:00
#include <linux/slab.h>
#include <linux/cpu.h>
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
#include <linux/average.h>
static int napi_weight = NAPI_POLL_WEIGHT;
module_param(napi_weight, int, 0444);
static bool csum = true, gso = true;
module_param(csum, bool, 0444);
module_param(gso, bool, 0444);
/* FIXME: MTU in config. */
virtio-net: mergeable buffer size should include virtio-net header Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size. However, the merge buffer size does not take into account the size of the virtio-net header. Consequently, packets that are MTU-size will take two buffers intead of one (to store the virtio-net header), substantially decreasing the throughput of MTU-size traffic due to TCP window / SKB truesize effects. This commit changes the mergeable buffer size to include the virtio-net header. The buffer size is cacheline-aligned because skb_page_frag_refill will not automatically align the requested size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs and vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Transmit offloads and mergeable receive buffers are enabled, but guest_tso4 / guest_csum are explicitly disabled to force MTU-sized packets on the receiver. next-net trunk before 2613af0ed18a (PAGE_SIZE buf): 3861.08Gb/s net-next trunk (MTU 1500- packet uses two buf due to size bug): 4076.62Gb/s net-next trunk (MTU 1480- packet fits in one buf): 6301.34Gb/s net-next trunk w/ size fix (MTU 1500 - packet fits in one buf): 6445.44Gb/s Suggested-by: Eric Northup <digitaleric@google.com> Signed-off-by: Michael Dalton <mwdalton@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14 22:41:04 +04:00
#define GOOD_PACKET_LEN (ETH_HLEN + VLAN_HLEN + ETH_DATA_LEN)
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
#define GOOD_COPY_LEN 128
#define VIRTNET_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD)
/* Amount of XDP headroom to prepend to packets for use by xdp_adjust_head */
#define VIRTIO_XDP_HEADROOM 256
/* RX packet size EWMA. The average packet size is used to determine the packet
* buffer size when refilling RX rings. As the entire RX ring may be refilled
* at once, the weight is chosen so that the EWMA will be insensitive to short-
* term, transient changes in packet size.
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
*/
DECLARE_EWMA(pkt_len, 0, 64)
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
/* With mergeable buffers we align buffer address and use the low bits to
* encode its true size. Buffer size is up to 1 page so we need to align to
* square root of page size to ensure we reserve enough bits to encode the true
* size.
*/
#define MERGEABLE_BUFFER_MIN_ALIGN_SHIFT ((PAGE_SHIFT + 1) / 2)
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
/* Minimum alignment for mergeable packet buffers. */
#define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, \
1 << MERGEABLE_BUFFER_MIN_ALIGN_SHIFT)
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
#define VIRTNET_DRIVER_VERSION "1.0.0"
struct virtnet_stats {
struct u64_stats_sync tx_syncp;
struct u64_stats_sync rx_syncp;
u64 tx_bytes;
u64 tx_packets;
u64 rx_bytes;
u64 rx_packets;
};
/* Internal representation of a send virtqueue */
struct send_queue {
/* Virtqueue associated with this send _queue */
struct virtqueue *vq;
/* TX: fragments + linear part + virtio header */
struct scatterlist sg[MAX_SKB_FRAGS + 2];
/* Name of the send queue: output.$index */
char name[40];
};
/* Internal representation of a receive virtqueue */
struct receive_queue {
/* Virtqueue associated with this receive_queue */
struct virtqueue *vq;
struct napi_struct napi;
struct bpf_prog __rcu *xdp_prog;
/* Chain pages by the private ptr. */
struct page *pages;
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
/* Average packet length for mergeable receive buffers. */
struct ewma_pkt_len mrg_avg_pkt_len;
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
/* Page frag for packet buffer allocation. */
struct page_frag alloc_frag;
/* RX: fragments + linear part + virtio header */
struct scatterlist sg[MAX_SKB_FRAGS + 2];
/* Name of this receive queue: input.$index */
char name[40];
};
struct virtnet_info {
struct virtio_device *vdev;
struct virtqueue *cvq;
struct net_device *dev;
struct send_queue *sq;
struct receive_queue *rq;
unsigned int status;
/* Max # of queue pairs supported by the device */
u16 max_queue_pairs;
/* # of queue pairs currently used by the driver */
u16 curr_queue_pairs;
/* # of XDP queue pairs currently used by the driver */
u16 xdp_queue_pairs;
/* I like... big packets and I cannot lie! */
bool big_packets;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
/* Host will merge rx buffers for big packets (shake it! shake it!) */
bool mergeable_rx_bufs;
/* Has control virtqueue */
bool has_cvq;
/* Host can handle any s/g split between our header and packet data */
bool any_header_sg;
/* Packet virtio header size */
u8 hdr_len;
/* Active statistics */
struct virtnet_stats __percpu *stats;
/* Work struct for refilling if we run low on memory. */
struct delayed_work refill;
/* Work struct for config space updates */
struct work_struct config_work;
/* Does the affinity hint is set for virtqueues? */
bool affinity_hint_set;
/* CPU hotplug instances for online & dead */
struct hlist_node node;
struct hlist_node node_dead;
/* Control VQ buffers: protected by the rtnl lock */
struct virtio_net_ctrl_hdr ctrl_hdr;
virtio_net_ctrl_ack ctrl_status;
struct virtio_net_ctrl_mq ctrl_mq;
u8 ctrl_promisc;
u8 ctrl_allmulti;
u16 ctrl_vid;
/* Ethtool settings */
u8 duplex;
u32 speed;
};
struct padded_vnet_hdr {
struct virtio_net_hdr_mrg_rxbuf hdr;
/*
* hdr is in a separate sg buffer, and data sg buffer shares same page
* with this header sg. This padding makes next sg 16 byte aligned
* after the header.
*/
char padding[4];
};
/* Converting between virtqueue no. and kernel tx/rx queue no.
* 0:rx0 1:tx0 2:rx1 3:tx1 ... 2N:rxN 2N+1:txN 2N+2:cvq
*/
static int vq2txq(struct virtqueue *vq)
{
return (vq->index - 1) / 2;
}
static int txq2vq(int txq)
{
return txq * 2 + 1;
}
static int vq2rxq(struct virtqueue *vq)
{
return vq->index / 2;
}
static int rxq2vq(int rxq)
{
return rxq * 2;
}
static inline struct virtio_net_hdr_mrg_rxbuf *skb_vnet_hdr(struct sk_buff *skb)
{
return (struct virtio_net_hdr_mrg_rxbuf *)skb->cb;
}
/*
* private is used to chain pages for big packets, put the whole
* most recent used list in the beginning for reuse
*/
static void give_pages(struct receive_queue *rq, struct page *page)
{
struct page *end;
/* Find end of list, sew whole thing into vi->rq.pages. */
for (end = page; end->private; end = (struct page *)end->private);
end->private = (unsigned long)rq->pages;
rq->pages = page;
}
static struct page *get_a_page(struct receive_queue *rq, gfp_t gfp_mask)
{
struct page *p = rq->pages;
if (p) {
rq->pages = (struct page *)p->private;
/* clear private here, it is used to chain pages */
p->private = 0;
} else
p = alloc_page(gfp_mask);
return p;
}
static void virtqueue_napi_schedule(struct napi_struct *napi,
struct virtqueue *vq)
{
if (napi_schedule_prep(napi)) {
virtqueue_disable_cb(vq);
__napi_schedule(napi);
}
}
static void virtqueue_napi_complete(struct napi_struct *napi,
struct virtqueue *vq, int processed)
{
int opaque;
opaque = virtqueue_enable_cb_prepare(vq);
if (napi_complete_done(napi, processed) &&
unlikely(virtqueue_poll(vq, opaque)))
virtqueue_napi_schedule(napi, vq);
}
static void skb_xmit_done(struct virtqueue *vq)
{
struct virtnet_info *vi = vq->vdev->priv;
/* Suppress further interrupts. */
virtqueue_disable_cb(vq);
/* We were probably waiting for more output buffers. */
netif_wake_subqueue(vi->dev, vq2txq(vq));
}
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
static unsigned int mergeable_ctx_to_buf_truesize(unsigned long mrg_ctx)
{
unsigned int truesize = mrg_ctx & (MERGEABLE_BUFFER_ALIGN - 1);
return (truesize + 1) * MERGEABLE_BUFFER_ALIGN;
}
static void *mergeable_ctx_to_buf_address(unsigned long mrg_ctx)
{
return (void *)(mrg_ctx & -MERGEABLE_BUFFER_ALIGN);
}
static unsigned long mergeable_buf_to_ctx(void *buf, unsigned int truesize)
{
unsigned int size = truesize / MERGEABLE_BUFFER_ALIGN;
return (unsigned long)buf | (size - 1);
}
/* Called from bottom half context */
static struct sk_buff *page_to_skb(struct virtnet_info *vi,
struct receive_queue *rq,
struct page *page, unsigned int offset,
unsigned int len, unsigned int truesize)
{
struct sk_buff *skb;
struct virtio_net_hdr_mrg_rxbuf *hdr;
unsigned int copy, hdr_len, hdr_padded_len;
char *p;
p = page_address(page) + offset;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
/* copy small packet so we can reuse these pages for small data */
skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN);
if (unlikely(!skb))
return NULL;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
hdr = skb_vnet_hdr(skb);
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
hdr_len = vi->hdr_len;
if (vi->mergeable_rx_bufs)
hdr_padded_len = sizeof *hdr;
else
hdr_padded_len = sizeof(struct padded_vnet_hdr);
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
memcpy(hdr, p, hdr_len);
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
len -= hdr_len;
offset += hdr_padded_len;
p += hdr_padded_len;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
copy = len;
if (copy > skb_tailroom(skb))
copy = skb_tailroom(skb);
memcpy(skb_put(skb, copy), p, copy);
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
len -= copy;
offset += copy;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
if (vi->mergeable_rx_bufs) {
if (len)
skb_add_rx_frag(skb, 0, page, offset, len, truesize);
else
put_page(page);
return skb;
}
/*
* Verify that we can indeed put this data into a skb.
* This is here to handle cases when the device erroneously
* tries to receive more than is possible. This is usually
* the case of a broken device.
*/
if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) {
net_dbg_ratelimited("%s: too much data\n", skb->dev->name);
dev_kfree_skb(skb);
return NULL;
}
BUG_ON(offset >= PAGE_SIZE);
while (len) {
unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len);
skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset,
frag_size, truesize);
len -= frag_size;
page = (struct page *)page->private;
offset = 0;
}
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
if (page)
give_pages(rq, page);
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
return skb;
}
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
bpf: add initial bpf tracepoints This work adds a number of tracepoints to paths that are either considered slow-path or exception-like states, where monitoring or inspecting them would be desirable. For bpf(2) syscall, tracepoints have been placed for main commands when they succeed. In XDP case, tracepoint is for exceptions, that is, f.e. on abnormal BPF program exit such as unknown or XDP_ABORTED return code, or when error occurs during XDP_TX action and the packet could not be forwarded. Both have been split into separate event headers, and can be further extended. Worst case, if they unexpectedly should get into our way in future, they can also removed [1]. Of course, these tracepoints (like any other) can be analyzed by eBPF itself, etc. Example output: # ./perf record -a -e bpf:* sleep 10 # ./perf script sock_example 6197 [005] 283.980322: bpf:bpf_map_create: map type=ARRAY ufd=4 key=4 val=8 max=256 flags=0 sock_example 6197 [005] 283.980721: bpf:bpf_prog_load: prog=a5ea8fa30ea6849c type=SOCKET_FILTER ufd=5 sock_example 6197 [005] 283.988423: bpf:bpf_prog_get_type: prog=a5ea8fa30ea6849c type=SOCKET_FILTER sock_example 6197 [005] 283.988443: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[06 00 00 00] val=[00 00 00 00 00 00 00 00] [...] sock_example 6197 [005] 288.990868: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[01 00 00 00] val=[14 00 00 00 00 00 00 00] swapper 0 [005] 289.338243: bpf:bpf_prog_put_rcu: prog=a5ea8fa30ea6849c type=SOCKET_FILTER [1] https://lwn.net/Articles/705270/ Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 04:28:18 +03:00
static bool virtnet_xdp_xmit(struct virtnet_info *vi,
struct receive_queue *rq,
struct xdp_buff *xdp)
{
struct virtio_net_hdr_mrg_rxbuf *hdr;
unsigned int len;
struct send_queue *sq;
unsigned int qp;
void *xdp_sent;
int err;
qp = vi->curr_queue_pairs - vi->xdp_queue_pairs + smp_processor_id();
sq = &vi->sq[qp];
/* Free up any pending old buffers before queueing new ones. */
while ((xdp_sent = virtqueue_get_buf(sq->vq, &len)) != NULL) {
struct page *sent_page = virt_to_head_page(xdp_sent);
put_page(sent_page);
}
xdp->data -= vi->hdr_len;
/* Zero header and leave csum up to XDP layers */
hdr = xdp->data;
memset(hdr, 0, vi->hdr_len);
sg_init_one(sq->sg, xdp->data, xdp->data_end - xdp->data);
err = virtqueue_add_outbuf(sq->vq, sq->sg, 1, xdp->data, GFP_ATOMIC);
if (unlikely(err)) {
struct page *page = virt_to_head_page(xdp->data);
put_page(page);
bpf: add initial bpf tracepoints This work adds a number of tracepoints to paths that are either considered slow-path or exception-like states, where monitoring or inspecting them would be desirable. For bpf(2) syscall, tracepoints have been placed for main commands when they succeed. In XDP case, tracepoint is for exceptions, that is, f.e. on abnormal BPF program exit such as unknown or XDP_ABORTED return code, or when error occurs during XDP_TX action and the packet could not be forwarded. Both have been split into separate event headers, and can be further extended. Worst case, if they unexpectedly should get into our way in future, they can also removed [1]. Of course, these tracepoints (like any other) can be analyzed by eBPF itself, etc. Example output: # ./perf record -a -e bpf:* sleep 10 # ./perf script sock_example 6197 [005] 283.980322: bpf:bpf_map_create: map type=ARRAY ufd=4 key=4 val=8 max=256 flags=0 sock_example 6197 [005] 283.980721: bpf:bpf_prog_load: prog=a5ea8fa30ea6849c type=SOCKET_FILTER ufd=5 sock_example 6197 [005] 283.988423: bpf:bpf_prog_get_type: prog=a5ea8fa30ea6849c type=SOCKET_FILTER sock_example 6197 [005] 283.988443: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[06 00 00 00] val=[00 00 00 00 00 00 00 00] [...] sock_example 6197 [005] 288.990868: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[01 00 00 00] val=[14 00 00 00 00 00 00 00] swapper 0 [005] 289.338243: bpf:bpf_prog_put_rcu: prog=a5ea8fa30ea6849c type=SOCKET_FILTER [1] https://lwn.net/Articles/705270/ Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 04:28:18 +03:00
return false;
}
virtqueue_kick(sq->vq);
bpf: add initial bpf tracepoints This work adds a number of tracepoints to paths that are either considered slow-path or exception-like states, where monitoring or inspecting them would be desirable. For bpf(2) syscall, tracepoints have been placed for main commands when they succeed. In XDP case, tracepoint is for exceptions, that is, f.e. on abnormal BPF program exit such as unknown or XDP_ABORTED return code, or when error occurs during XDP_TX action and the packet could not be forwarded. Both have been split into separate event headers, and can be further extended. Worst case, if they unexpectedly should get into our way in future, they can also removed [1]. Of course, these tracepoints (like any other) can be analyzed by eBPF itself, etc. Example output: # ./perf record -a -e bpf:* sleep 10 # ./perf script sock_example 6197 [005] 283.980322: bpf:bpf_map_create: map type=ARRAY ufd=4 key=4 val=8 max=256 flags=0 sock_example 6197 [005] 283.980721: bpf:bpf_prog_load: prog=a5ea8fa30ea6849c type=SOCKET_FILTER ufd=5 sock_example 6197 [005] 283.988423: bpf:bpf_prog_get_type: prog=a5ea8fa30ea6849c type=SOCKET_FILTER sock_example 6197 [005] 283.988443: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[06 00 00 00] val=[00 00 00 00 00 00 00 00] [...] sock_example 6197 [005] 288.990868: bpf:bpf_map_lookup_elem: map type=ARRAY ufd=4 key=[01 00 00 00] val=[14 00 00 00 00 00 00 00] swapper 0 [005] 289.338243: bpf:bpf_prog_put_rcu: prog=a5ea8fa30ea6849c type=SOCKET_FILTER [1] https://lwn.net/Articles/705270/ Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25 04:28:18 +03:00
return true;
}
static unsigned int virtnet_get_headroom(struct virtnet_info *vi)
{
return vi->xdp_queue_pairs ? VIRTIO_XDP_HEADROOM : 0;
}
static struct sk_buff *receive_small(struct net_device *dev,
struct virtnet_info *vi,
struct receive_queue *rq,
void *buf, unsigned int len)
{
struct sk_buff *skb;
struct bpf_prog *xdp_prog;
unsigned int xdp_headroom = virtnet_get_headroom(vi);
unsigned int header_offset = VIRTNET_RX_PAD + xdp_headroom;
unsigned int headroom = vi->hdr_len + header_offset;
unsigned int buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
unsigned int delta = 0;
len -= vi->hdr_len;
rcu_read_lock();
xdp_prog = rcu_dereference(rq->xdp_prog);
if (xdp_prog) {
struct virtio_net_hdr_mrg_rxbuf *hdr = buf + header_offset;
struct xdp_buff xdp;
void *orig_data;
u32 act;
if (unlikely(hdr->hdr.gso_type || hdr->hdr.flags))
goto err_xdp;
xdp.data_hard_start = buf + VIRTNET_RX_PAD + vi->hdr_len;
xdp.data = xdp.data_hard_start + xdp_headroom;
xdp.data_end = xdp.data + len;
orig_data = xdp.data;
act = bpf_prog_run_xdp(xdp_prog, &xdp);
switch (act) {
case XDP_PASS:
/* Recalculate length in case bpf program changed it */
delta = orig_data - xdp.data;
break;
case XDP_TX:
if (unlikely(!virtnet_xdp_xmit(vi, rq, &xdp)))
trace_xdp_exception(vi->dev, xdp_prog, act);
rcu_read_unlock();
goto xdp_xmit;
default:
bpf_warn_invalid_xdp_action(act);
case XDP_ABORTED:
trace_xdp_exception(vi->dev, xdp_prog, act);
case XDP_DROP:
goto err_xdp;
}
}
rcu_read_unlock();
skb = build_skb(buf, buflen);
if (!skb) {
put_page(virt_to_head_page(buf));
goto err;
}
skb_reserve(skb, headroom - delta);
skb_put(skb, len + delta);
if (!delta) {
buf += header_offset;
memcpy(skb_vnet_hdr(skb), buf, vi->hdr_len);
} /* keep zeroed vnet hdr since packet was changed by bpf */
err:
return skb;
err_xdp:
rcu_read_unlock();
dev->stats.rx_dropped++;
put_page(virt_to_head_page(buf));
xdp_xmit:
return NULL;
}
static struct sk_buff *receive_big(struct net_device *dev,
struct virtnet_info *vi,
struct receive_queue *rq,
void *buf,
unsigned int len)
{
struct page *page = buf;
struct sk_buff *skb = page_to_skb(vi, rq, page, 0, len, PAGE_SIZE);
if (unlikely(!skb))
goto err;
return skb;
err:
dev->stats.rx_dropped++;
give_pages(rq, page);
return NULL;
}
/* The conditions to enable XDP should preclude the underlying device from
* sending packets across multiple buffers (num_buf > 1). However per spec
* it does not appear to be illegal to do so but rather just against convention.
* So in order to avoid making a system unresponsive the packets are pushed
* into a page and the XDP program is run. This will be extremely slow and we
* push a warning to the user to fix this as soon as possible. Fixing this may
* require resolving the underlying hardware to determine why multiple buffers
* are being received or simply loading the XDP program in the ingress stack
* after the skb is built because there is no advantage to running it here
* anymore.
*/
static struct page *xdp_linearize_page(struct receive_queue *rq,
u16 *num_buf,
struct page *p,
int offset,
unsigned int *len)
{
struct page *page = alloc_page(GFP_ATOMIC);
unsigned int page_off = VIRTIO_XDP_HEADROOM;
if (!page)
return NULL;
memcpy(page_address(page) + page_off, page_address(p) + offset, *len);
page_off += *len;
while (--*num_buf) {
unsigned int buflen;
unsigned long ctx;
void *buf;
int off;
ctx = (unsigned long)virtqueue_get_buf(rq->vq, &buflen);
if (unlikely(!ctx))
goto err_buf;
buf = mergeable_ctx_to_buf_address(ctx);
p = virt_to_head_page(buf);
off = buf - page_address(p);
/* guard against a misconfigured or uncooperative backend that
* is sending packet larger than the MTU.
*/
if ((page_off + buflen) > PAGE_SIZE) {
put_page(p);
goto err_buf;
}
memcpy(page_address(page) + page_off,
page_address(p) + off, buflen);
page_off += buflen;
put_page(p);
}
/* Headroom does not contribute to packet length */
*len = page_off - VIRTIO_XDP_HEADROOM;
return page;
err_buf:
__free_pages(page, 0);
return NULL;
}
static struct sk_buff *receive_mergeable(struct net_device *dev,
struct virtnet_info *vi,
struct receive_queue *rq,
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
unsigned long ctx,
unsigned int len)
{
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
void *buf = mergeable_ctx_to_buf_address(ctx);
struct virtio_net_hdr_mrg_rxbuf *hdr = buf;
u16 num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);
struct page *page = virt_to_head_page(buf);
int offset = buf - page_address(page);
struct sk_buff *head_skb, *curr_skb;
struct bpf_prog *xdp_prog;
unsigned int truesize;
head_skb = NULL;
rcu_read_lock();
xdp_prog = rcu_dereference(rq->xdp_prog);
if (xdp_prog) {
struct page *xdp_page;
struct xdp_buff xdp;
void *data;
u32 act;
/* This happens when rx buffer size is underestimated */
if (unlikely(num_buf > 1)) {
/* linearize data for XDP */
xdp_page = xdp_linearize_page(rq, &num_buf,
page, offset, &len);
if (!xdp_page)
goto err_xdp;
offset = VIRTIO_XDP_HEADROOM;
} else {
xdp_page = page;
}
/* Transient failure which in theory could occur if
* in-flight packets from before XDP was enabled reach
* the receive path after XDP is loaded. In practice I
* was not able to create this condition.
*/
if (unlikely(hdr->hdr.gso_type))
goto err_xdp;
/* Allow consuming headroom but reserve enough space to push
* the descriptor on if we get an XDP_TX return code.
*/
data = page_address(xdp_page) + offset;
xdp.data_hard_start = data - VIRTIO_XDP_HEADROOM + vi->hdr_len;
xdp.data = data + vi->hdr_len;
xdp.data_end = xdp.data + (len - vi->hdr_len);
act = bpf_prog_run_xdp(xdp_prog, &xdp);
switch (act) {
case XDP_PASS:
/* recalculate offset to account for any header
* adjustments. Note other cases do not build an
* skb and avoid using offset
*/
offset = xdp.data -
page_address(xdp_page) - vi->hdr_len;
/* We can only create skb based on xdp_page. */
if (unlikely(xdp_page != page)) {
rcu_read_unlock();
put_page(page);
head_skb = page_to_skb(vi, rq, xdp_page,
offset, len, PAGE_SIZE);
ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
return head_skb;
}
break;
case XDP_TX:
if (unlikely(!virtnet_xdp_xmit(vi, rq, &xdp)))
trace_xdp_exception(vi->dev, xdp_prog, act);
ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
if (unlikely(xdp_page != page))
goto err_xdp;
rcu_read_unlock();
goto xdp_xmit;
default:
bpf_warn_invalid_xdp_action(act);
case XDP_ABORTED:
trace_xdp_exception(vi->dev, xdp_prog, act);
case XDP_DROP:
if (unlikely(xdp_page != page))
__free_pages(xdp_page, 0);
ewma_pkt_len_add(&rq->mrg_avg_pkt_len, len);
goto err_xdp;
}
}
rcu_read_unlock();
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
head_skb = page_to_skb(vi, rq, page, offset, len, truesize);
curr_skb = head_skb;
if (unlikely(!curr_skb))
goto err_skb;
while (--num_buf) {
int num_skb_frags;
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
if (unlikely(!ctx)) {
pr_debug("%s: rx error: %d buffers out of %d missing\n",
dev->name, num_buf,
virtio16_to_cpu(vi->vdev,
hdr->num_buffers));
dev->stats.rx_length_errors++;
goto err_buf;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
}
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
buf = mergeable_ctx_to_buf_address(ctx);
page = virt_to_head_page(buf);
num_skb_frags = skb_shinfo(curr_skb)->nr_frags;
if (unlikely(num_skb_frags == MAX_SKB_FRAGS)) {
struct sk_buff *nskb = alloc_skb(0, GFP_ATOMIC);
if (unlikely(!nskb))
goto err_skb;
if (curr_skb == head_skb)
skb_shinfo(curr_skb)->frag_list = nskb;
else
curr_skb->next = nskb;
curr_skb = nskb;
head_skb->truesize += nskb->truesize;
num_skb_frags = 0;
}
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
truesize = max(len, mergeable_ctx_to_buf_truesize(ctx));
if (curr_skb != head_skb) {
head_skb->data_len += len;
head_skb->len += len;
head_skb->truesize += truesize;
}
offset = buf - page_address(page);
virtio-net: coalesce rx frags when possible during rx Commit 2613af0ed18a11d5c566a81f9a6510b73180660a (virtio_net: migrate mergeable rx buffers to page frag allocators) try to increase the payload/truesize for MTU-sized traffic. But this will introduce the extra overhead for GSO packets received because of the frag list. This commit tries to reduce this issue by coalesce the possible rx frags when possible during rx. Test result shows the about 15% improvement on full size GSO packet receiving (and even better than before commit 2613af0ed18a11d5c566a81f9a6510b73180660a). Before this commit: ./netperf -H 192.168.100.4 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.100.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 20303.87 After this commit: ./netperf -H 192.168.100.4 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.100.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 23841.26 Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Michael Dalton <mwdalton@google.com> Cc: Eric Dumazet <edumazet@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-01 10:07:48 +04:00
if (skb_can_coalesce(curr_skb, num_skb_frags, page, offset)) {
put_page(page);
skb_coalesce_rx_frag(curr_skb, num_skb_frags - 1,
len, truesize);
virtio-net: coalesce rx frags when possible during rx Commit 2613af0ed18a11d5c566a81f9a6510b73180660a (virtio_net: migrate mergeable rx buffers to page frag allocators) try to increase the payload/truesize for MTU-sized traffic. But this will introduce the extra overhead for GSO packets received because of the frag list. This commit tries to reduce this issue by coalesce the possible rx frags when possible during rx. Test result shows the about 15% improvement on full size GSO packet receiving (and even better than before commit 2613af0ed18a11d5c566a81f9a6510b73180660a). Before this commit: ./netperf -H 192.168.100.4 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.100.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 20303.87 After this commit: ./netperf -H 192.168.100.4 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.100.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 23841.26 Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Michael Dalton <mwdalton@google.com> Cc: Eric Dumazet <edumazet@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-01 10:07:48 +04:00
} else {
skb_add_rx_frag(curr_skb, num_skb_frags, page,
offset, len, truesize);
virtio-net: coalesce rx frags when possible during rx Commit 2613af0ed18a11d5c566a81f9a6510b73180660a (virtio_net: migrate mergeable rx buffers to page frag allocators) try to increase the payload/truesize for MTU-sized traffic. But this will introduce the extra overhead for GSO packets received because of the frag list. This commit tries to reduce this issue by coalesce the possible rx frags when possible during rx. Test result shows the about 15% improvement on full size GSO packet receiving (and even better than before commit 2613af0ed18a11d5c566a81f9a6510b73180660a). Before this commit: ./netperf -H 192.168.100.4 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.100.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 20303.87 After this commit: ./netperf -H 192.168.100.4 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.100.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 23841.26 Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Michael Dalton <mwdalton@google.com> Cc: Eric Dumazet <edumazet@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-01 10:07:48 +04:00
}
}
ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);
return head_skb;
err_xdp:
rcu_read_unlock();
err_skb:
put_page(page);
while (--num_buf) {
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
ctx = (unsigned long)virtqueue_get_buf(rq->vq, &len);
if (unlikely(!ctx)) {
pr_debug("%s: rx error: %d buffers missing\n",
dev->name, num_buf);
dev->stats.rx_length_errors++;
break;
}
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
page = virt_to_head_page(mergeable_ctx_to_buf_address(ctx));
put_page(page);
}
err_buf:
dev->stats.rx_dropped++;
dev_kfree_skb(head_skb);
xdp_xmit:
return NULL;
}
static int receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
void *buf, unsigned int len)
{
struct net_device *dev = vi->dev;
struct sk_buff *skb;
struct virtio_net_hdr_mrg_rxbuf *hdr;
int ret;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
pr_debug("%s: short packet %i\n", dev->name, len);
dev->stats.rx_length_errors++;
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
if (vi->mergeable_rx_bufs) {
unsigned long ctx = (unsigned long)buf;
void *base = mergeable_ctx_to_buf_address(ctx);
put_page(virt_to_head_page(base));
} else if (vi->big_packets) {
give_pages(rq, buf);
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
} else {
put_page(virt_to_head_page(buf));
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
}
return 0;
}
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
if (vi->mergeable_rx_bufs)
skb = receive_mergeable(dev, vi, rq, (unsigned long)buf, len);
else if (vi->big_packets)
skb = receive_big(dev, vi, rq, buf, len);
else
skb = receive_small(dev, vi, rq, buf, len);
if (unlikely(!skb))
return 0;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
hdr = skb_vnet_hdr(skb);
ret = skb->len;
if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
skb->ip_summed = CHECKSUM_UNNECESSARY;
if (virtio_net_hdr_to_skb(skb, &hdr->hdr,
virtio_is_little_endian(vi->vdev))) {
net_warn_ratelimited("%s: bad gso: type: %u, size: %u\n",
dev->name, hdr->hdr.gso_type,
hdr->hdr.gso_size);
goto frame_err;
}
skb->protocol = eth_type_trans(skb, dev);
pr_debug("Receiving skb proto 0x%04x len %i type %i\n",
ntohs(skb->protocol), skb->len, skb->pkt_type);
napi_gro_receive(&rq->napi, skb);
return ret;
frame_err:
dev->stats.rx_frame_errors++;
dev_kfree_skb(skb);
return 0;
}
static int add_recvbuf_small(struct virtnet_info *vi, struct receive_queue *rq,
gfp_t gfp)
{
struct page_frag *alloc_frag = &rq->alloc_frag;
char *buf;
unsigned int xdp_headroom = virtnet_get_headroom(vi);
int len = vi->hdr_len + VIRTNET_RX_PAD + GOOD_PACKET_LEN + xdp_headroom;
int err;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
len = SKB_DATA_ALIGN(len) +
SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
if (unlikely(!skb_page_frag_refill(len, alloc_frag, gfp)))
return -ENOMEM;
buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
get_page(alloc_frag->page);
alloc_frag->offset += len;
sg_init_one(rq->sg, buf + VIRTNET_RX_PAD + xdp_headroom,
vi->hdr_len + GOOD_PACKET_LEN);
err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, buf, gfp);
if (err < 0)
put_page(virt_to_head_page(buf));
return err;
}
static int add_recvbuf_big(struct virtnet_info *vi, struct receive_queue *rq,
gfp_t gfp)
{
struct page *first, *list = NULL;
char *p;
int i, err, offset;
sg_init_table(rq->sg, MAX_SKB_FRAGS + 2);
/* page in rq->sg[MAX_SKB_FRAGS + 1] is list tail */
for (i = MAX_SKB_FRAGS + 1; i > 1; --i) {
first = get_a_page(rq, gfp);
if (!first) {
if (list)
give_pages(rq, list);
return -ENOMEM;
}
sg_set_buf(&rq->sg[i], page_address(first), PAGE_SIZE);
/* chain new page in list head to match sg */
first->private = (unsigned long)list;
list = first;
}
first = get_a_page(rq, gfp);
if (!first) {
give_pages(rq, list);
return -ENOMEM;
}
p = page_address(first);
/* rq->sg[0], rq->sg[1] share the same page */
/* a separated rq->sg[0] for header - required in case !any_header_sg */
sg_set_buf(&rq->sg[0], p, vi->hdr_len);
/* rq->sg[1] for data packet, from offset */
offset = sizeof(struct padded_vnet_hdr);
sg_set_buf(&rq->sg[1], p + offset, PAGE_SIZE - offset);
/* chain first in list head */
first->private = (unsigned long)list;
err = virtqueue_add_inbuf(rq->vq, rq->sg, MAX_SKB_FRAGS + 2,
first, gfp);
if (err < 0)
give_pages(rq, first);
return err;
}
static unsigned int get_mergeable_buf_len(struct ewma_pkt_len *avg_pkt_len)
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
{
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
const size_t hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
unsigned int len;
len = hdr_len + clamp_t(unsigned int, ewma_pkt_len_read(avg_pkt_len),
GOOD_PACKET_LEN, PAGE_SIZE - hdr_len);
return ALIGN(len, MERGEABLE_BUFFER_ALIGN);
}
static int add_recvbuf_mergeable(struct virtnet_info *vi,
struct receive_queue *rq, gfp_t gfp)
{
struct page_frag *alloc_frag = &rq->alloc_frag;
unsigned int headroom = virtnet_get_headroom(vi);
char *buf;
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
unsigned long ctx;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
int err;
unsigned int len, hole;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
len = get_mergeable_buf_len(&rq->mrg_avg_pkt_len);
if (unlikely(!skb_page_frag_refill(len + headroom, alloc_frag, gfp)))
return -ENOMEM;
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset;
buf += headroom; /* advance address leaving hole at front of pkt */
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
ctx = mergeable_buf_to_ctx(buf, len);
get_page(alloc_frag->page);
alloc_frag->offset += len + headroom;
hole = alloc_frag->size - alloc_frag->offset;
if (hole < len + headroom) {
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
/* To avoid internal fragmentation, if there is very likely not
* enough space for another buffer, add the remaining space to
* the current buffer. This extra space is not included in
* the truesize stored in ctx.
*/
len += hole;
alloc_frag->offset += hole;
}
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
sg_init_one(rq->sg, buf, len);
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
err = virtqueue_add_inbuf(rq->vq, rq->sg, 1, (void *)ctx, gfp);
if (err < 0)
put_page(virt_to_head_page(buf));
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
return err;
}
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
/*
* Returns false if we couldn't fill entirely (OOM).
*
* Normally run in the receive path, but can also be run from ndo_open
* before we're receiving packets, or from refill_work which is
* careful to disable receiving (using napi_disable).
*/
static bool try_fill_recv(struct virtnet_info *vi, struct receive_queue *rq,
gfp_t gfp)
{
int err;
bool oom;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
gfp |= __GFP_COLD;
do {
if (vi->mergeable_rx_bufs)
err = add_recvbuf_mergeable(vi, rq, gfp);
else if (vi->big_packets)
err = add_recvbuf_big(vi, rq, gfp);
else
err = add_recvbuf_small(vi, rq, gfp);
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
oom = err == -ENOMEM;
if (err)
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
break;
Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches. You can see my solution in my pending-rebases branch, if that helps, but I know you love merging: https://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=commit;h=12e4e64fa66a4c812e4855de32abdb4d819526fe Cheers, Rusty. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAABAgAGBQJQz/vKAAoJENkgDmzRrbjx+eYQAK/egj9T8Nnth6mkzdbCFSO7 Bciga2hDiudGCiGojTRGPRSc0VP9LgfvPbY2pxX+R9CfEqR+a8q/rRQhCS79ZwPB /mJy3HNiCx418HZxgwNtk6vPe0PjJm6SsjbXeB9hB+PQLCbdwA0BjpG6xjF/jitP noPqhhXreeQgYVxAKoFPvff/Byu2GlNnDdVMQxWRmo8hTKlTCzl0T/7BHRxthhJj iOrXTFzrT/osPT0zyqlngT03T4wlBvL2Bfw8d/kuRPEZ71dpIctWeH2KzdwXVCrz hFQGxAz4OWvW3xrNwj7c6O3SWj4VemUMjQqeA/PtRiOEI5gM0Y/Bit47dWL4wM/O OWUKFHzq4DFs8MmwXBgDDXl5xOjOBH9Ik4FZayn3Y7COT/B8CjFdOC2MdDGmZ9yd NInumg7FqP+u12g+9Vq8S/b0cfoQm4qFe8VHiPJu+jRmCZglyvLjk7oq/QwW8Gaq Pkzit1Ey0DWo2KvZ4D/nuXJCuhmzN/AJ10M48lLYZhtOIVg9gsa0xjhfgq4FnvSK xFCf3rcWnlGIXcOYh/hKU25WaCLzBuqMuSK35A72IujrQOL7OJTk4Oqote3Z3H9B 08XJmyW6SOZdfw17X4Im1jbyuLek///xQJ9Jw/tya7j9lBt8zjJ+FmLPs4mLGEOm WJv9uZPs+QbIMNky2Lcb =myDR -----END PGP SIGNATURE----- Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...
2012-12-20 20:37:04 +04:00
} while (rq->vq->num_free);
virtqueue_kick(rq->vq);
return !oom;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
}
static void skb_recv_done(struct virtqueue *rvq)
{
struct virtnet_info *vi = rvq->vdev->priv;
struct receive_queue *rq = &vi->rq[vq2rxq(rvq)];
virtqueue_napi_schedule(&rq->napi, rvq);
}
static void virtnet_napi_enable(struct virtqueue *vq, struct napi_struct *napi)
{
napi_enable(napi);
/* If all buffers were filled by other side before we napi_enabled, we
* won't get another interrupt, so process any outstanding packets now.
* Call local_bh_enable after to trigger softIRQ processing.
*/
local_bh_disable();
virtqueue_napi_schedule(napi, vq);
local_bh_enable();
}
static void refill_work(struct work_struct *work)
{
struct virtnet_info *vi =
container_of(work, struct virtnet_info, refill.work);
bool still_empty;
int i;
for (i = 0; i < vi->curr_queue_pairs; i++) {
struct receive_queue *rq = &vi->rq[i];
napi_disable(&rq->napi);
still_empty = !try_fill_recv(vi, rq, GFP_KERNEL);
virtnet_napi_enable(rq->vq, &rq->napi);
/* In theory, this can happen: if we don't get any buffers in
* we will *never* try to fill again.
*/
if (still_empty)
schedule_delayed_work(&vi->refill, HZ/2);
}
}
static int virtnet_receive(struct receive_queue *rq, int budget)
{
struct virtnet_info *vi = rq->vq->vdev->priv;
unsigned int len, received = 0, bytes = 0;
void *buf;
struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
while (received < budget &&
(buf = virtqueue_get_buf(rq->vq, &len)) != NULL) {
bytes += receive_buf(vi, rq, buf, len);
received++;
}
if (rq->vq->num_free > virtqueue_get_vring_size(rq->vq) / 2) {
if (!try_fill_recv(vi, rq, GFP_ATOMIC))
schedule_delayed_work(&vi->refill, 0);
}
u64_stats_update_begin(&stats->rx_syncp);
stats->rx_bytes += bytes;
stats->rx_packets += received;
u64_stats_update_end(&stats->rx_syncp);
return received;
}
static int virtnet_poll(struct napi_struct *napi, int budget)
{
struct receive_queue *rq =
container_of(napi, struct receive_queue, napi);
unsigned int received;
received = virtnet_receive(rq, budget);
/* Out of packets? */
if (received < budget)
virtqueue_napi_complete(napi, rq->vq, received);
return received;
}
static int virtnet_open(struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
int i;
for (i = 0; i < vi->max_queue_pairs; i++) {
if (i < vi->curr_queue_pairs)
/* Make sure we have some buffers: if oom use wq. */
if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
schedule_delayed_work(&vi->refill, 0);
virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
}
return 0;
}
Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches. You can see my solution in my pending-rebases branch, if that helps, but I know you love merging: https://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=commit;h=12e4e64fa66a4c812e4855de32abdb4d819526fe Cheers, Rusty. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAABAgAGBQJQz/vKAAoJENkgDmzRrbjx+eYQAK/egj9T8Nnth6mkzdbCFSO7 Bciga2hDiudGCiGojTRGPRSc0VP9LgfvPbY2pxX+R9CfEqR+a8q/rRQhCS79ZwPB /mJy3HNiCx418HZxgwNtk6vPe0PjJm6SsjbXeB9hB+PQLCbdwA0BjpG6xjF/jitP noPqhhXreeQgYVxAKoFPvff/Byu2GlNnDdVMQxWRmo8hTKlTCzl0T/7BHRxthhJj iOrXTFzrT/osPT0zyqlngT03T4wlBvL2Bfw8d/kuRPEZ71dpIctWeH2KzdwXVCrz hFQGxAz4OWvW3xrNwj7c6O3SWj4VemUMjQqeA/PtRiOEI5gM0Y/Bit47dWL4wM/O OWUKFHzq4DFs8MmwXBgDDXl5xOjOBH9Ik4FZayn3Y7COT/B8CjFdOC2MdDGmZ9yd NInumg7FqP+u12g+9Vq8S/b0cfoQm4qFe8VHiPJu+jRmCZglyvLjk7oq/QwW8Gaq Pkzit1Ey0DWo2KvZ4D/nuXJCuhmzN/AJ10M48lLYZhtOIVg9gsa0xjhfgq4FnvSK xFCf3rcWnlGIXcOYh/hKU25WaCLzBuqMuSK35A72IujrQOL7OJTk4Oqote3Z3H9B 08XJmyW6SOZdfw17X4Im1jbyuLek///xQJ9Jw/tya7j9lBt8zjJ+FmLPs4mLGEOm WJv9uZPs+QbIMNky2Lcb =myDR -----END PGP SIGNATURE----- Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...
2012-12-20 20:37:04 +04:00
static void free_old_xmit_skbs(struct send_queue *sq)
{
struct sk_buff *skb;
unsigned int len;
struct virtnet_info *vi = sq->vq->vdev->priv;
struct virtnet_stats *stats = this_cpu_ptr(vi->stats);
unsigned int packets = 0;
unsigned int bytes = 0;
while ((skb = virtqueue_get_buf(sq->vq, &len)) != NULL) {
pr_debug("Sent skb %p\n", skb);
bytes += skb->len;
packets++;
virtio_net: use dev_kfree_skb_any() in free_old_xmit_skbs() Because netpoll can call netdevice start_xmit() method with irqs disabled, drivers should not call kfree_skb() from their start_xmit(), but use dev_kfree_skb_any() instead. Oct 8 11:16:52 172.30.1.31 [113074.791813] ------------[ cut here ]------------ Oct 8 11:16:52 172.30.1.31 [113074.791813] WARNING: at net/core/skbuff.c:398 \ skb_release_head_state+0x64/0xc8() Oct 8 11:16:52 172.30.1.31 [113074.791813] Hardware name: Oct 8 11:16:52 172.30.1.31 [113074.791813] Modules linked in: netconsole ocfs2 jbd2 quota_tree \ ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs crc32c drbd cn loop \ serio_raw psmouse snd_pcm snd_timer snd soundcore snd_page_alloc virtio_net pcspkr parport_pc parport \ i2c_piix4 i2c_core button processor evdev ext3 jbd mbcache dm_mirror dm_region_hash dm_log dm_snapshot \ dm_mod ide_cd_mod cdrom ata_generic ata_piix virtio_blk libata scsi_mod piix ide_pci_generic ide_core \ virtio_pci virtio_ring virtio floppy thermal fan thermal_sys [last unloaded: netconsole] Oct 8 11:16:52 172.30.1.31 [113074.791813] Pid: 11132, comm: php5-cgi Tainted: G W \ 2.6.31.2-vserver #1 Oct 8 11:16:52 172.30.1.31 [113074.791813] Call Trace: Oct 8 11:16:52 172.30.1.31 [113074.791813] <IRQ> [<ffffffff81253cd5>] ? \ skb_release_head_state+0x64/0xc8 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81253cd5>] ? skb_release_head_state+0x64/0xc8 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81049ae1>] ? warn_slowpath_common+0x77/0xa3 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81253cd5>] ? skb_release_head_state+0x64/0xc8 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81253a1a>] ? __kfree_skb+0x9/0x7d Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffffa01cb139>] ? free_old_xmit_skbs+0x51/0x6e \ [virtio_net] Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffffa01cbc85>] ? start_xmit+0x26/0xf2 [virtio_net] Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff8126934f>] ? netpoll_send_skb+0xd2/0x205 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffffa0429216>] ? write_msg+0x90/0xeb [netconsole] Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81049f06>] ? __call_console_drivers+0x5e/0x6f Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff8102b49d>] ? kvm_clock_read+0x4d/0x52 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff8104a082>] ? release_console_sem+0x115/0x1ba Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff8104a632>] ? vprintk+0x2f2/0x34b Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff8106b142>] ? vx_update_load+0x18/0x13e Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81308309>] ? printk+0x4e/0x5d Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff8102b49d>] ? kvm_clock_read+0x4d/0x52 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81070b62>] ? getnstimeofday+0x55/0xaf Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81062683>] ? ktime_get_ts+0x21/0x49 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff810626b7>] ? ktime_get+0xc/0x41 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81062788>] ? hrtimer_interrupt+0x9c/0x146 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81024a4b>] ? smp_apic_timer_interrupt+0x80/0x93 Oct 8 11:16:52 172.30.1.31 [113074.791813] [<ffffffff81011663>] ? apic_timer_interrupt+0x13/0x20 Oct 8 11:16:52 172.30.1.31 [113074.791813] <EOI> [<ffffffff8130a9eb>] ? _spin_unlock_irq+0xd/0x31 Reported-and-tested-by: Massimo Cetra <mcetra@navynet.it> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Bug-Entry: http://bugzilla.kernel.org/show_bug.cgi?id=14378 Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-14 18:36:43 +04:00
dev_kfree_skb_any(skb);
}
/* Avoid overhead when no packets have been processed
* happens when called speculatively from start_xmit.
*/
if (!packets)
return;
u64_stats_update_begin(&stats->tx_syncp);
stats->tx_bytes += bytes;
stats->tx_packets += packets;
u64_stats_update_end(&stats->tx_syncp);
}
static int xmit_skb(struct send_queue *sq, struct sk_buff *skb)
{
struct virtio_net_hdr_mrg_rxbuf *hdr;
const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
struct virtnet_info *vi = sq->vq->vdev->priv;
unsigned num_sg;
unsigned hdr_len = vi->hdr_len;
bool can_push;
pr_debug("%s: xmit %p %pM\n", vi->dev->name, skb, dest);
can_push = vi->any_header_sg &&
!((unsigned long)skb->data & (__alignof__(*hdr) - 1)) &&
!skb_header_cloned(skb) && skb_headroom(skb) >= hdr_len;
/* Even if we can, don't push here yet as this would skew
* csum_start offset below. */
if (can_push)
hdr = (struct virtio_net_hdr_mrg_rxbuf *)(skb->data - hdr_len);
else
hdr = skb_vnet_hdr(skb);
if (virtio_net_hdr_from_skb(skb, &hdr->hdr,
virtio_is_little_endian(vi->vdev), false))
BUG();
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
if (vi->mergeable_rx_bufs)
hdr->num_buffers = 0;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
sg_init_table(sq->sg, skb_shinfo(skb)->nr_frags + (can_push ? 1 : 2));
if (can_push) {
__skb_push(skb, hdr_len);
num_sg = skb_to_sgvec(skb, sq->sg, 0, skb->len);
/* Pull header back to avoid skew in tx bytes calculations. */
__skb_pull(skb, hdr_len);
} else {
sg_set_buf(sq->sg, hdr, hdr_len);
num_sg = skb_to_sgvec(skb, sq->sg + 1, 0, skb->len) + 1;
}
return virtqueue_add_outbuf(sq->vq, sq->sg, num_sg, skb, GFP_ATOMIC);
}
static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
int qnum = skb_get_queue_mapping(skb);
struct send_queue *sq = &vi->sq[qnum];
int err;
struct netdev_queue *txq = netdev_get_tx_queue(dev, qnum);
bool kick = !skb->xmit_more;
/* Free up any pending old buffers before queueing new ones. */
free_old_xmit_skbs(sq);
/* timestamp packet in software */
skb_tx_timestamp(skb);
/* Try to transmit */
Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches. You can see my solution in my pending-rebases branch, if that helps, but I know you love merging: https://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=commit;h=12e4e64fa66a4c812e4855de32abdb4d819526fe Cheers, Rusty. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAABAgAGBQJQz/vKAAoJENkgDmzRrbjx+eYQAK/egj9T8Nnth6mkzdbCFSO7 Bciga2hDiudGCiGojTRGPRSc0VP9LgfvPbY2pxX+R9CfEqR+a8q/rRQhCS79ZwPB /mJy3HNiCx418HZxgwNtk6vPe0PjJm6SsjbXeB9hB+PQLCbdwA0BjpG6xjF/jitP noPqhhXreeQgYVxAKoFPvff/Byu2GlNnDdVMQxWRmo8hTKlTCzl0T/7BHRxthhJj iOrXTFzrT/osPT0zyqlngT03T4wlBvL2Bfw8d/kuRPEZ71dpIctWeH2KzdwXVCrz hFQGxAz4OWvW3xrNwj7c6O3SWj4VemUMjQqeA/PtRiOEI5gM0Y/Bit47dWL4wM/O OWUKFHzq4DFs8MmwXBgDDXl5xOjOBH9Ik4FZayn3Y7COT/B8CjFdOC2MdDGmZ9yd NInumg7FqP+u12g+9Vq8S/b0cfoQm4qFe8VHiPJu+jRmCZglyvLjk7oq/QwW8Gaq Pkzit1Ey0DWo2KvZ4D/nuXJCuhmzN/AJ10M48lLYZhtOIVg9gsa0xjhfgq4FnvSK xFCf3rcWnlGIXcOYh/hKU25WaCLzBuqMuSK35A72IujrQOL7OJTk4Oqote3Z3H9B 08XJmyW6SOZdfw17X4Im1jbyuLek///xQJ9Jw/tya7j9lBt8zjJ+FmLPs4mLGEOm WJv9uZPs+QbIMNky2Lcb =myDR -----END PGP SIGNATURE----- Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...
2012-12-20 20:37:04 +04:00
err = xmit_skb(sq, skb);
/* This should not happen! */
if (unlikely(err)) {
dev->stats.tx_fifo_errors++;
if (net_ratelimit())
dev_warn(&dev->dev,
Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches. You can see my solution in my pending-rebases branch, if that helps, but I know you love merging: https://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=commit;h=12e4e64fa66a4c812e4855de32abdb4d819526fe Cheers, Rusty. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAABAgAGBQJQz/vKAAoJENkgDmzRrbjx+eYQAK/egj9T8Nnth6mkzdbCFSO7 Bciga2hDiudGCiGojTRGPRSc0VP9LgfvPbY2pxX+R9CfEqR+a8q/rRQhCS79ZwPB /mJy3HNiCx418HZxgwNtk6vPe0PjJm6SsjbXeB9hB+PQLCbdwA0BjpG6xjF/jitP noPqhhXreeQgYVxAKoFPvff/Byu2GlNnDdVMQxWRmo8hTKlTCzl0T/7BHRxthhJj iOrXTFzrT/osPT0zyqlngT03T4wlBvL2Bfw8d/kuRPEZ71dpIctWeH2KzdwXVCrz hFQGxAz4OWvW3xrNwj7c6O3SWj4VemUMjQqeA/PtRiOEI5gM0Y/Bit47dWL4wM/O OWUKFHzq4DFs8MmwXBgDDXl5xOjOBH9Ik4FZayn3Y7COT/B8CjFdOC2MdDGmZ9yd NInumg7FqP+u12g+9Vq8S/b0cfoQm4qFe8VHiPJu+jRmCZglyvLjk7oq/QwW8Gaq Pkzit1Ey0DWo2KvZ4D/nuXJCuhmzN/AJ10M48lLYZhtOIVg9gsa0xjhfgq4FnvSK xFCf3rcWnlGIXcOYh/hKU25WaCLzBuqMuSK35A72IujrQOL7OJTk4Oqote3Z3H9B 08XJmyW6SOZdfw17X4Im1jbyuLek///xQJ9Jw/tya7j9lBt8zjJ+FmLPs4mLGEOm WJv9uZPs+QbIMNky2Lcb =myDR -----END PGP SIGNATURE----- Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...
2012-12-20 20:37:04 +04:00
"Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
dev->stats.tx_dropped++;
dev_kfree_skb_any(skb);
return NETDEV_TX_OK;
}
/* Don't wait up for transmitted skbs to be freed. */
skb_orphan(skb);
nf_reset(skb);
/* If running out of space, stop queue to avoid getting packets that we
* are then unable to transmit.
* An alternative would be to force queuing layer to requeue the skb by
* returning NETDEV_TX_BUSY. However, NETDEV_TX_BUSY should not be
* returned in a normal path of operation: it means that driver is not
* maintaining the TX queue stop/start state properly, and causes
* the stack to do a non-trivial amount of useless work.
* Since most packets only take 1 or 2 ring slots, stopping the queue
* early means 16 slots are typically wasted.
*/
Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches. You can see my solution in my pending-rebases branch, if that helps, but I know you love merging: https://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=commit;h=12e4e64fa66a4c812e4855de32abdb4d819526fe Cheers, Rusty. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAABAgAGBQJQz/vKAAoJENkgDmzRrbjx+eYQAK/egj9T8Nnth6mkzdbCFSO7 Bciga2hDiudGCiGojTRGPRSc0VP9LgfvPbY2pxX+R9CfEqR+a8q/rRQhCS79ZwPB /mJy3HNiCx418HZxgwNtk6vPe0PjJm6SsjbXeB9hB+PQLCbdwA0BjpG6xjF/jitP noPqhhXreeQgYVxAKoFPvff/Byu2GlNnDdVMQxWRmo8hTKlTCzl0T/7BHRxthhJj iOrXTFzrT/osPT0zyqlngT03T4wlBvL2Bfw8d/kuRPEZ71dpIctWeH2KzdwXVCrz hFQGxAz4OWvW3xrNwj7c6O3SWj4VemUMjQqeA/PtRiOEI5gM0Y/Bit47dWL4wM/O OWUKFHzq4DFs8MmwXBgDDXl5xOjOBH9Ik4FZayn3Y7COT/B8CjFdOC2MdDGmZ9yd NInumg7FqP+u12g+9Vq8S/b0cfoQm4qFe8VHiPJu+jRmCZglyvLjk7oq/QwW8Gaq Pkzit1Ey0DWo2KvZ4D/nuXJCuhmzN/AJ10M48lLYZhtOIVg9gsa0xjhfgq4FnvSK xFCf3rcWnlGIXcOYh/hKU25WaCLzBuqMuSK35A72IujrQOL7OJTk4Oqote3Z3H9B 08XJmyW6SOZdfw17X4Im1jbyuLek///xQJ9Jw/tya7j9lBt8zjJ+FmLPs4mLGEOm WJv9uZPs+QbIMNky2Lcb =myDR -----END PGP SIGNATURE----- Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...
2012-12-20 20:37:04 +04:00
if (sq->vq->num_free < 2+MAX_SKB_FRAGS) {
netif_stop_subqueue(dev, qnum);
if (unlikely(!virtqueue_enable_cb_delayed(sq->vq))) {
/* More just got used, free them then recheck. */
Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches. You can see my solution in my pending-rebases branch, if that helps, but I know you love merging: https://git.kernel.org/?p=linux/kernel/git/rusty/linux.git;a=commit;h=12e4e64fa66a4c812e4855de32abdb4d819526fe Cheers, Rusty. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAABAgAGBQJQz/vKAAoJENkgDmzRrbjx+eYQAK/egj9T8Nnth6mkzdbCFSO7 Bciga2hDiudGCiGojTRGPRSc0VP9LgfvPbY2pxX+R9CfEqR+a8q/rRQhCS79ZwPB /mJy3HNiCx418HZxgwNtk6vPe0PjJm6SsjbXeB9hB+PQLCbdwA0BjpG6xjF/jitP noPqhhXreeQgYVxAKoFPvff/Byu2GlNnDdVMQxWRmo8hTKlTCzl0T/7BHRxthhJj iOrXTFzrT/osPT0zyqlngT03T4wlBvL2Bfw8d/kuRPEZ71dpIctWeH2KzdwXVCrz hFQGxAz4OWvW3xrNwj7c6O3SWj4VemUMjQqeA/PtRiOEI5gM0Y/Bit47dWL4wM/O OWUKFHzq4DFs8MmwXBgDDXl5xOjOBH9Ik4FZayn3Y7COT/B8CjFdOC2MdDGmZ9yd NInumg7FqP+u12g+9Vq8S/b0cfoQm4qFe8VHiPJu+jRmCZglyvLjk7oq/QwW8Gaq Pkzit1Ey0DWo2KvZ4D/nuXJCuhmzN/AJ10M48lLYZhtOIVg9gsa0xjhfgq4FnvSK xFCf3rcWnlGIXcOYh/hKU25WaCLzBuqMuSK35A72IujrQOL7OJTk4Oqote3Z3H9B 08XJmyW6SOZdfw17X4Im1jbyuLek///xQJ9Jw/tya7j9lBt8zjJ+FmLPs4mLGEOm WJv9uZPs+QbIMNky2Lcb =myDR -----END PGP SIGNATURE----- Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull virtio update from Rusty Russell: "Some nice cleanups, and even a patch my wife did as a "live" demo for Latinoware 2012. There's a slightly non-trivial merge in virtio-net, as we cleaned up the virtio add_buf interface while DaveM accepted the mq virtio-net patches." * tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (27 commits) virtio_console: Add support for remoteproc serial virtio_console: Merge struct buffer_token into struct port_buffer virtio: add drv_to_virtio to make code clearly virtio: use dev_to_virtio wrapper in virtio virtio-mmio: Fix irq parsing in command line parameter virtio_console: Free buffers from out-queue upon close virtio: Convert dev_printk(KERN_<LEVEL> to dev_<level>( virtio_console: Use kmalloc instead of kzalloc virtio_console: Free buffer if splice fails virtio: tools: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: scsi: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: rpmsg: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: net: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: console: make it clear that virtqueue_add_buf() no longer returns > 0 virtio: make virtqueue_add_buf() returning 0 on success, not capacity. virtio: console: don't rely on virtqueue_add_buf() returning capacity. virtio_net: don't rely on virtqueue_add_buf() returning capacity. virtio-net: remove unused skb_vnet_hdr->num_sg field virtio-net: correct capacity math on ring full virtio: move queue_index and num_free fields into core struct virtqueue. ...
2012-12-20 20:37:04 +04:00
free_old_xmit_skbs(sq);
if (sq->vq->num_free >= 2+MAX_SKB_FRAGS) {
netif_start_subqueue(dev, qnum);
virtqueue_disable_cb(sq->vq);
}
}
}
if (kick || netif_xmit_stopped(txq))
virtqueue_kick(sq->vq);
return NETDEV_TX_OK;
}
/*
* Send command via the control virtqueue and check status. Commands
* supported by the hypervisor, as indicated by feature bits, should
* never fail unless improperly formatted.
*/
static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
struct scatterlist *out)
{
struct scatterlist *sgs[4], hdr, stat;
unsigned out_num = 0, tmp;
/* Caller should know better */
BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
vi->ctrl_status = ~0;
vi->ctrl_hdr.class = class;
vi->ctrl_hdr.cmd = cmd;
/* Add header */
sg_init_one(&hdr, &vi->ctrl_hdr, sizeof(vi->ctrl_hdr));
sgs[out_num++] = &hdr;
if (out)
sgs[out_num++] = out;
/* Add return status. */
sg_init_one(&stat, &vi->ctrl_status, sizeof(vi->ctrl_status));
sgs[out_num] = &stat;
BUG_ON(out_num + 1 > ARRAY_SIZE(sgs));
virtqueue_add_sgs(vi->cvq, sgs, out_num, 1, vi, GFP_ATOMIC);
if (unlikely(!virtqueue_kick(vi->cvq)))
return vi->ctrl_status == VIRTIO_NET_OK;
/* Spin for a response, the kick causes an ioport write, trapping
* into the hypervisor, so the request should be handled immediately.
*/
while (!virtqueue_get_buf(vi->cvq, &tmp) &&
!virtqueue_is_broken(vi->cvq))
cpu_relax();
return vi->ctrl_status == VIRTIO_NET_OK;
}
static int virtnet_set_mac_address(struct net_device *dev, void *p)
{
struct virtnet_info *vi = netdev_priv(dev);
struct virtio_device *vdev = vi->vdev;
int ret;
struct sockaddr *addr;
struct scatterlist sg;
addr = kmemdup(p, sizeof(*addr), GFP_KERNEL);
if (!addr)
return -ENOMEM;
ret = eth_prepare_mac_addr_change(dev, addr);
if (ret)
goto out;
if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR)) {
sg_init_one(&sg, addr->sa_data, dev->addr_len);
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
VIRTIO_NET_CTRL_MAC_ADDR_SET, &sg)) {
dev_warn(&vdev->dev,
"Failed to set mac address by vq command.\n");
ret = -EINVAL;
goto out;
}
} else if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC) &&
!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) {
unsigned int i;
/* Naturally, this has an atomicity problem. */
for (i = 0; i < dev->addr_len; i++)
virtio_cwrite8(vdev,
offsetof(struct virtio_net_config, mac) +
i, addr->sa_data[i]);
}
eth_commit_mac_addr_change(dev, p);
ret = 0;
out:
kfree(addr);
return ret;
}
static void virtnet_stats(struct net_device *dev,
struct rtnl_link_stats64 *tot)
{
struct virtnet_info *vi = netdev_priv(dev);
int cpu;
unsigned int start;
for_each_possible_cpu(cpu) {
struct virtnet_stats *stats = per_cpu_ptr(vi->stats, cpu);
u64 tpackets, tbytes, rpackets, rbytes;
do {
start = u64_stats_fetch_begin_irq(&stats->tx_syncp);
tpackets = stats->tx_packets;
tbytes = stats->tx_bytes;
} while (u64_stats_fetch_retry_irq(&stats->tx_syncp, start));
do {
start = u64_stats_fetch_begin_irq(&stats->rx_syncp);
rpackets = stats->rx_packets;
rbytes = stats->rx_bytes;
} while (u64_stats_fetch_retry_irq(&stats->rx_syncp, start));
tot->rx_packets += rpackets;
tot->tx_packets += tpackets;
tot->rx_bytes += rbytes;
tot->tx_bytes += tbytes;
}
tot->tx_dropped = dev->stats.tx_dropped;
tot->tx_fifo_errors = dev->stats.tx_fifo_errors;
tot->rx_dropped = dev->stats.rx_dropped;
tot->rx_length_errors = dev->stats.rx_length_errors;
tot->rx_frame_errors = dev->stats.rx_frame_errors;
}
#ifdef CONFIG_NET_POLL_CONTROLLER
static void virtnet_netpoll(struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
int i;
for (i = 0; i < vi->curr_queue_pairs; i++)
napi_schedule(&vi->rq[i].napi);
}
#endif
static void virtnet_ack_link_announce(struct virtnet_info *vi)
{
rtnl_lock();
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_ANNOUNCE,
VIRTIO_NET_CTRL_ANNOUNCE_ACK, NULL))
dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
rtnl_unlock();
}
static int _virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
{
struct scatterlist sg;
struct net_device *dev = vi->dev;
if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
return 0;
vi->ctrl_mq.virtqueue_pairs = cpu_to_virtio16(vi->vdev, queue_pairs);
sg_init_one(&sg, &vi->ctrl_mq, sizeof(vi->ctrl_mq));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET, &sg)) {
dev_warn(&dev->dev, "Fail to set num of queue pairs to %d\n",
queue_pairs);
return -EINVAL;
} else {
vi->curr_queue_pairs = queue_pairs;
/* virtnet_open() will refill when device is going to up. */
if (dev->flags & IFF_UP)
schedule_delayed_work(&vi->refill, 0);
}
return 0;
}
static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
{
int err;
rtnl_lock();
err = _virtnet_set_queues(vi, queue_pairs);
rtnl_unlock();
return err;
}
static int virtnet_close(struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
int i;
/* Make sure refill_work doesn't re-enable napi! */
cancel_delayed_work_sync(&vi->refill);
for (i = 0; i < vi->max_queue_pairs; i++)
napi_disable(&vi->rq[i].napi);
return 0;
}
static void virtnet_set_rx_mode(struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
struct scatterlist sg[2];
struct virtio_net_ctrl_mac *mac_data;
struct netdev_hw_addr *ha;
int uc_count;
int mc_count;
void *buf;
int i;
/* We can't dynamically set ndo_set_rx_mode, so return gracefully */
if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_RX))
return;
vi->ctrl_promisc = ((dev->flags & IFF_PROMISC) != 0);
vi->ctrl_allmulti = ((dev->flags & IFF_ALLMULTI) != 0);
sg_init_one(sg, &vi->ctrl_promisc, sizeof(vi->ctrl_promisc));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
VIRTIO_NET_CTRL_RX_PROMISC, sg))
dev_warn(&dev->dev, "Failed to %sable promisc mode.\n",
vi->ctrl_promisc ? "en" : "dis");
sg_init_one(sg, &vi->ctrl_allmulti, sizeof(vi->ctrl_allmulti));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_RX,
VIRTIO_NET_CTRL_RX_ALLMULTI, sg))
dev_warn(&dev->dev, "Failed to %sable allmulti mode.\n",
vi->ctrl_allmulti ? "en" : "dis");
uc_count = netdev_uc_count(dev);
mc_count = netdev_mc_count(dev);
/* MAC filter - use one buffer for both lists */
buf = kzalloc(((uc_count + mc_count) * ETH_ALEN) +
(2 * sizeof(mac_data->entries)), GFP_ATOMIC);
mac_data = buf;
if (!buf)
return;
sg_init_table(sg, 2);
/* Store the unicast list and count in the front of the buffer */
mac_data->entries = cpu_to_virtio32(vi->vdev, uc_count);
i = 0;
netdev_for_each_uc_addr(ha, dev)
memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
sg_set_buf(&sg[0], mac_data,
sizeof(mac_data->entries) + (uc_count * ETH_ALEN));
/* multicast list and count fill the end */
mac_data = (void *)&mac_data->macs[uc_count][0];
mac_data->entries = cpu_to_virtio32(vi->vdev, mc_count);
i = 0;
netdev_for_each_mc_addr(ha, dev)
memcpy(&mac_data->macs[i++][0], ha->addr, ETH_ALEN);
sg_set_buf(&sg[1], mac_data,
sizeof(mac_data->entries) + (mc_count * ETH_ALEN));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MAC,
VIRTIO_NET_CTRL_MAC_TABLE_SET, sg))
dev_warn(&dev->dev, "Failed to set MAC filter table.\n");
kfree(buf);
}
static int virtnet_vlan_rx_add_vid(struct net_device *dev,
__be16 proto, u16 vid)
{
struct virtnet_info *vi = netdev_priv(dev);
struct scatterlist sg;
vi->ctrl_vid = vid;
sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
VIRTIO_NET_CTRL_VLAN_ADD, &sg))
dev_warn(&dev->dev, "Failed to add VLAN ID %d.\n", vid);
return 0;
}
static int virtnet_vlan_rx_kill_vid(struct net_device *dev,
__be16 proto, u16 vid)
{
struct virtnet_info *vi = netdev_priv(dev);
struct scatterlist sg;
vi->ctrl_vid = vid;
sg_init_one(&sg, &vi->ctrl_vid, sizeof(vi->ctrl_vid));
if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_VLAN,
VIRTIO_NET_CTRL_VLAN_DEL, &sg))
dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
return 0;
}
static void virtnet_clean_affinity(struct virtnet_info *vi, long hcpu)
{
int i;
if (vi->affinity_hint_set) {
for (i = 0; i < vi->max_queue_pairs; i++) {
virtqueue_set_affinity(vi->rq[i].vq, -1);
virtqueue_set_affinity(vi->sq[i].vq, -1);
}
vi->affinity_hint_set = false;
}
}
static void virtnet_set_affinity(struct virtnet_info *vi)
{
int i;
int cpu;
/* In multiqueue mode, when the number of cpu is equal to the number of
* queue pairs, we let the queue pairs to be private to one cpu by
* setting the affinity hint to eliminate the contention.
*/
if (vi->curr_queue_pairs == 1 ||
vi->max_queue_pairs != num_online_cpus()) {
virtnet_clean_affinity(vi, -1);
return;
}
i = 0;
for_each_online_cpu(cpu) {
virtqueue_set_affinity(vi->rq[i].vq, cpu);
virtqueue_set_affinity(vi->sq[i].vq, cpu);
netif_set_xps_queue(vi->dev, cpumask_of(cpu), i);
i++;
}
vi->affinity_hint_set = true;
}
static int virtnet_cpu_online(unsigned int cpu, struct hlist_node *node)
{
struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
node);
virtnet_set_affinity(vi);
return 0;
}
static int virtnet_cpu_dead(unsigned int cpu, struct hlist_node *node)
{
struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
node_dead);
virtnet_set_affinity(vi);
return 0;
}
static int virtnet_cpu_down_prep(unsigned int cpu, struct hlist_node *node)
{
struct virtnet_info *vi = hlist_entry_safe(node, struct virtnet_info,
node);
virtnet_clean_affinity(vi, cpu);
return 0;
}
static enum cpuhp_state virtionet_online;
static int virtnet_cpu_notif_add(struct virtnet_info *vi)
{
int ret;
ret = cpuhp_state_add_instance_nocalls(virtionet_online, &vi->node);
if (ret)
return ret;
ret = cpuhp_state_add_instance_nocalls(CPUHP_VIRT_NET_DEAD,
&vi->node_dead);
if (!ret)
return ret;
cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
return ret;
}
static void virtnet_cpu_notif_remove(struct virtnet_info *vi)
{
cpuhp_state_remove_instance_nocalls(virtionet_online, &vi->node);
cpuhp_state_remove_instance_nocalls(CPUHP_VIRT_NET_DEAD,
&vi->node_dead);
}
static void virtnet_get_ringparam(struct net_device *dev,
struct ethtool_ringparam *ring)
{
struct virtnet_info *vi = netdev_priv(dev);
ring->rx_max_pending = virtqueue_get_vring_size(vi->rq[0].vq);
ring->tx_max_pending = virtqueue_get_vring_size(vi->sq[0].vq);
ring->rx_pending = ring->rx_max_pending;
ring->tx_pending = ring->tx_max_pending;
}
static void virtnet_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *info)
{
struct virtnet_info *vi = netdev_priv(dev);
struct virtio_device *vdev = vi->vdev;
strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
strlcpy(info->version, VIRTNET_DRIVER_VERSION, sizeof(info->version));
strlcpy(info->bus_info, virtio_bus_name(vdev), sizeof(info->bus_info));
}
/* TODO: Eliminate OOO packets during switching */
static int virtnet_set_channels(struct net_device *dev,
struct ethtool_channels *channels)
{
struct virtnet_info *vi = netdev_priv(dev);
u16 queue_pairs = channels->combined_count;
int err;
/* We don't support separate rx/tx channels.
* We don't allow setting 'other' channels.
*/
if (channels->rx_count || channels->tx_count || channels->other_count)
return -EINVAL;
if (queue_pairs > vi->max_queue_pairs || queue_pairs == 0)
return -EINVAL;
/* For now we don't support modifying channels while XDP is loaded
* also when XDP is loaded all RX queues have XDP programs so we only
* need to check a single RX queue.
*/
if (vi->rq[0].xdp_prog)
return -EINVAL;
get_online_cpus();
err = _virtnet_set_queues(vi, queue_pairs);
if (!err) {
netif_set_real_num_tx_queues(dev, queue_pairs);
netif_set_real_num_rx_queues(dev, queue_pairs);
virtnet_set_affinity(vi);
}
put_online_cpus();
return err;
}
static void virtnet_get_channels(struct net_device *dev,
struct ethtool_channels *channels)
{
struct virtnet_info *vi = netdev_priv(dev);
channels->combined_count = vi->curr_queue_pairs;
channels->max_combined = vi->max_queue_pairs;
channels->max_other = 0;
channels->rx_count = 0;
channels->tx_count = 0;
channels->other_count = 0;
}
/* Check if the user is trying to change anything besides speed/duplex */
static bool
virtnet_validate_ethtool_cmd(const struct ethtool_link_ksettings *cmd)
{
struct ethtool_link_ksettings diff1 = *cmd;
struct ethtool_link_ksettings diff2 = {};
/* cmd is always set so we need to clear it, validate the port type
* and also without autonegotiation we can ignore advertising
*/
diff1.base.speed = 0;
diff2.base.port = PORT_OTHER;
ethtool_link_ksettings_zero_link_mode(&diff1, advertising);
diff1.base.duplex = 0;
diff1.base.cmd = 0;
diff1.base.link_mode_masks_nwords = 0;
return !memcmp(&diff1.base, &diff2.base, sizeof(diff1.base)) &&
bitmap_empty(diff1.link_modes.supported,
__ETHTOOL_LINK_MODE_MASK_NBITS) &&
bitmap_empty(diff1.link_modes.advertising,
__ETHTOOL_LINK_MODE_MASK_NBITS) &&
bitmap_empty(diff1.link_modes.lp_advertising,
__ETHTOOL_LINK_MODE_MASK_NBITS);
}
static int virtnet_set_link_ksettings(struct net_device *dev,
const struct ethtool_link_ksettings *cmd)
{
struct virtnet_info *vi = netdev_priv(dev);
u32 speed;
speed = cmd->base.speed;
/* don't allow custom speed and duplex */
if (!ethtool_validate_speed(speed) ||
!ethtool_validate_duplex(cmd->base.duplex) ||
!virtnet_validate_ethtool_cmd(cmd))
return -EINVAL;
vi->speed = speed;
vi->duplex = cmd->base.duplex;
return 0;
}
static int virtnet_get_link_ksettings(struct net_device *dev,
struct ethtool_link_ksettings *cmd)
{
struct virtnet_info *vi = netdev_priv(dev);
cmd->base.speed = vi->speed;
cmd->base.duplex = vi->duplex;
cmd->base.port = PORT_OTHER;
return 0;
}
static void virtnet_init_settings(struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
vi->speed = SPEED_UNKNOWN;
vi->duplex = DUPLEX_UNKNOWN;
}
static const struct ethtool_ops virtnet_ethtool_ops = {
.get_drvinfo = virtnet_get_drvinfo,
.get_link = ethtool_op_get_link,
.get_ringparam = virtnet_get_ringparam,
.set_channels = virtnet_set_channels,
.get_channels = virtnet_get_channels,
.get_ts_info = ethtool_op_get_ts_info,
.get_link_ksettings = virtnet_get_link_ksettings,
.set_link_ksettings = virtnet_set_link_ksettings,
};
static void virtnet_freeze_down(struct virtio_device *vdev)
{
struct virtnet_info *vi = vdev->priv;
int i;
/* Make sure no work handler is accessing the device */
flush_work(&vi->config_work);
netif_device_detach(vi->dev);
cancel_delayed_work_sync(&vi->refill);
if (netif_running(vi->dev)) {
for (i = 0; i < vi->max_queue_pairs; i++)
napi_disable(&vi->rq[i].napi);
}
}
static int init_vqs(struct virtnet_info *vi);
static void _remove_vq_common(struct virtnet_info *vi);
static int virtnet_restore_up(struct virtio_device *vdev)
{
struct virtnet_info *vi = vdev->priv;
int err, i;
err = init_vqs(vi);
if (err)
return err;
virtio_device_ready(vdev);
if (netif_running(vi->dev)) {
for (i = 0; i < vi->curr_queue_pairs; i++)
if (!try_fill_recv(vi, &vi->rq[i], GFP_KERNEL))
schedule_delayed_work(&vi->refill, 0);
for (i = 0; i < vi->max_queue_pairs; i++)
virtnet_napi_enable(vi->rq[i].vq, &vi->rq[i].napi);
}
netif_device_attach(vi->dev);
return err;
}
virito-net: set queues after reset during xdp_set We set queues before reset which will cause a crash[1]. This is because is_xdp_raw_buffer_queue() depends on the old xdp queue pairs number to do the correct detection. So fix this by - passing xdp queue pairs and current queue pairs to virtnet_reset() - change vi->xdp_qp after reset but before refill, to make sure both free_unused_bufs() and refill can make correct detection of XDP. - remove the duplicated queue pairs setting before virtnet_reset() since we will do it inside virtnet_reset() [1] [ 74.328168] general protection fault: 0000 [#1] SMP [ 74.328625] Modules linked in: nfsd xfs libcrc32c virtio_net virtio_pci [ 74.329117] CPU: 0 PID: 2849 Comm: xdp2 Not tainted 4.10.0-rc7+ #499 [ 74.329577] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014 [ 74.330424] task: ffff88007a894000 task.stack: ffffc90004388000 [ 74.330844] RIP: 0010:skb_release_head_state+0x28/0x80 [ 74.331298] RSP: 0018:ffffc9000438b8d0 EFLAGS: 00010206 [ 74.331676] RAX: 0000000000000000 RBX: ffff88007ad96300 RCX: 0000000000000000 [ 74.332217] RDX: ffff88007fc137a8 RSI: ffff88007fc0db28 RDI: 0001bf00000001be [ 74.332758] RBP: ffffc9000438b8d8 R08: 000000000005008f R09: 00000000000005f9 [ 74.333274] R10: ffff88007d001700 R11: ffffffff820a8a4d R12: ffff88007ad96300 [ 74.333787] R13: 0000000000000002 R14: ffff880036604000 R15: 000077ff80000000 [ 74.334308] FS: 00007fc70d8a7b40(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 [ 74.334891] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 74.335314] CR2: 00007fff4144a710 CR3: 000000007ab56000 CR4: 00000000003406f0 [ 74.335830] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 74.336373] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 74.336895] Call Trace: [ 74.337086] skb_release_all+0xd/0x30 [ 74.337356] consume_skb+0x2c/0x90 [ 74.337607] free_unused_bufs+0x1ff/0x270 [virtio_net] [ 74.337988] ? vp_synchronize_vectors+0x3b/0x60 [virtio_pci] [ 74.338398] virtnet_xdp+0x21e/0x440 [virtio_net] [ 74.338741] dev_change_xdp_fd+0x101/0x140 [ 74.339048] do_setlink+0xcf4/0xd20 [ 74.339304] ? symcmp+0xf/0x20 [ 74.339529] ? mls_level_isvalid+0x52/0x60 [ 74.339828] ? mls_range_isvalid+0x43/0x50 [ 74.340135] ? nla_parse+0xa0/0x100 [ 74.340400] rtnl_setlink+0xd4/0x120 [ 74.340664] ? cpumask_next_and+0x30/0x50 [ 74.340966] rtnetlink_rcv_msg+0x7f/0x1f0 [ 74.341259] ? sock_has_perm+0x59/0x60 [ 74.341586] ? napi_consume_skb+0xe2/0x100 [ 74.342010] ? rtnl_newlink+0x890/0x890 [ 74.342435] netlink_rcv_skb+0x92/0xb0 [ 74.342846] rtnetlink_rcv+0x23/0x30 [ 74.343277] netlink_unicast+0x162/0x210 [ 74.343677] netlink_sendmsg+0x2db/0x390 [ 74.343968] sock_sendmsg+0x33/0x40 [ 74.344233] SYSC_sendto+0xee/0x160 [ 74.344482] ? SYSC_bind+0xb0/0xe0 [ 74.344806] ? sock_alloc_file+0x92/0x110 [ 74.345106] ? fd_install+0x20/0x30 [ 74.345360] ? sock_map_fd+0x3f/0x60 [ 74.345586] SyS_sendto+0x9/0x10 [ 74.345790] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 74.346086] RIP: 0033:0x7fc70d1b8f6d [ 74.346312] RSP: 002b:00007fff4144a708 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 74.346785] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fc70d1b8f6d [ 74.347244] RDX: 000000000000002c RSI: 00007fff4144a720 RDI: 0000000000000003 [ 74.347683] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 [ 74.348544] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff4144bd90 [ 74.349082] R13: 0000000000000002 R14: 0000000000000002 R15: 00007fff4144cda0 [ 74.349607] Code: 00 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 58 48 85 ff 74 0e 40 f6 c7 01 74 3d 48 c7 43 58 00 00 00 00 48 8b 7b 68 48 85 ff 74 05 <f0> ff 0f 74 20 48 8b 43 60 48 85 c0 74 14 65 8b 15 f3 ab 8d 7e [ 74.351008] RIP: skb_release_head_state+0x28/0x80 RSP: ffffc9000438b8d0 [ 74.351625] ---[ end trace fe6e19fd11cfc80b ]--- Fixes: 2de2f7f40ef9 ("virtio_net: XDP support for adjust_head") Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-20 06:50:20 +03:00
static int virtnet_reset(struct virtnet_info *vi, int curr_qp, int xdp_qp)
{
struct virtio_device *dev = vi->vdev;
int ret;
virtio_config_disable(dev);
dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
virtnet_freeze_down(dev);
_remove_vq_common(vi);
dev->config->reset(dev);
virtio_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER);
ret = virtio_finalize_features(dev);
if (ret)
goto err;
virito-net: set queues after reset during xdp_set We set queues before reset which will cause a crash[1]. This is because is_xdp_raw_buffer_queue() depends on the old xdp queue pairs number to do the correct detection. So fix this by - passing xdp queue pairs and current queue pairs to virtnet_reset() - change vi->xdp_qp after reset but before refill, to make sure both free_unused_bufs() and refill can make correct detection of XDP. - remove the duplicated queue pairs setting before virtnet_reset() since we will do it inside virtnet_reset() [1] [ 74.328168] general protection fault: 0000 [#1] SMP [ 74.328625] Modules linked in: nfsd xfs libcrc32c virtio_net virtio_pci [ 74.329117] CPU: 0 PID: 2849 Comm: xdp2 Not tainted 4.10.0-rc7+ #499 [ 74.329577] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014 [ 74.330424] task: ffff88007a894000 task.stack: ffffc90004388000 [ 74.330844] RIP: 0010:skb_release_head_state+0x28/0x80 [ 74.331298] RSP: 0018:ffffc9000438b8d0 EFLAGS: 00010206 [ 74.331676] RAX: 0000000000000000 RBX: ffff88007ad96300 RCX: 0000000000000000 [ 74.332217] RDX: ffff88007fc137a8 RSI: ffff88007fc0db28 RDI: 0001bf00000001be [ 74.332758] RBP: ffffc9000438b8d8 R08: 000000000005008f R09: 00000000000005f9 [ 74.333274] R10: ffff88007d001700 R11: ffffffff820a8a4d R12: ffff88007ad96300 [ 74.333787] R13: 0000000000000002 R14: ffff880036604000 R15: 000077ff80000000 [ 74.334308] FS: 00007fc70d8a7b40(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 [ 74.334891] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 74.335314] CR2: 00007fff4144a710 CR3: 000000007ab56000 CR4: 00000000003406f0 [ 74.335830] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 74.336373] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 74.336895] Call Trace: [ 74.337086] skb_release_all+0xd/0x30 [ 74.337356] consume_skb+0x2c/0x90 [ 74.337607] free_unused_bufs+0x1ff/0x270 [virtio_net] [ 74.337988] ? vp_synchronize_vectors+0x3b/0x60 [virtio_pci] [ 74.338398] virtnet_xdp+0x21e/0x440 [virtio_net] [ 74.338741] dev_change_xdp_fd+0x101/0x140 [ 74.339048] do_setlink+0xcf4/0xd20 [ 74.339304] ? symcmp+0xf/0x20 [ 74.339529] ? mls_level_isvalid+0x52/0x60 [ 74.339828] ? mls_range_isvalid+0x43/0x50 [ 74.340135] ? nla_parse+0xa0/0x100 [ 74.340400] rtnl_setlink+0xd4/0x120 [ 74.340664] ? cpumask_next_and+0x30/0x50 [ 74.340966] rtnetlink_rcv_msg+0x7f/0x1f0 [ 74.341259] ? sock_has_perm+0x59/0x60 [ 74.341586] ? napi_consume_skb+0xe2/0x100 [ 74.342010] ? rtnl_newlink+0x890/0x890 [ 74.342435] netlink_rcv_skb+0x92/0xb0 [ 74.342846] rtnetlink_rcv+0x23/0x30 [ 74.343277] netlink_unicast+0x162/0x210 [ 74.343677] netlink_sendmsg+0x2db/0x390 [ 74.343968] sock_sendmsg+0x33/0x40 [ 74.344233] SYSC_sendto+0xee/0x160 [ 74.344482] ? SYSC_bind+0xb0/0xe0 [ 74.344806] ? sock_alloc_file+0x92/0x110 [ 74.345106] ? fd_install+0x20/0x30 [ 74.345360] ? sock_map_fd+0x3f/0x60 [ 74.345586] SyS_sendto+0x9/0x10 [ 74.345790] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 74.346086] RIP: 0033:0x7fc70d1b8f6d [ 74.346312] RSP: 002b:00007fff4144a708 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 74.346785] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fc70d1b8f6d [ 74.347244] RDX: 000000000000002c RSI: 00007fff4144a720 RDI: 0000000000000003 [ 74.347683] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 [ 74.348544] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff4144bd90 [ 74.349082] R13: 0000000000000002 R14: 0000000000000002 R15: 00007fff4144cda0 [ 74.349607] Code: 00 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 58 48 85 ff 74 0e 40 f6 c7 01 74 3d 48 c7 43 58 00 00 00 00 48 8b 7b 68 48 85 ff 74 05 <f0> ff 0f 74 20 48 8b 43 60 48 85 c0 74 14 65 8b 15 f3 ab 8d 7e [ 74.351008] RIP: skb_release_head_state+0x28/0x80 RSP: ffffc9000438b8d0 [ 74.351625] ---[ end trace fe6e19fd11cfc80b ]--- Fixes: 2de2f7f40ef9 ("virtio_net: XDP support for adjust_head") Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-20 06:50:20 +03:00
vi->xdp_queue_pairs = xdp_qp;
ret = virtnet_restore_up(dev);
if (ret)
goto err;
virito-net: set queues after reset during xdp_set We set queues before reset which will cause a crash[1]. This is because is_xdp_raw_buffer_queue() depends on the old xdp queue pairs number to do the correct detection. So fix this by - passing xdp queue pairs and current queue pairs to virtnet_reset() - change vi->xdp_qp after reset but before refill, to make sure both free_unused_bufs() and refill can make correct detection of XDP. - remove the duplicated queue pairs setting before virtnet_reset() since we will do it inside virtnet_reset() [1] [ 74.328168] general protection fault: 0000 [#1] SMP [ 74.328625] Modules linked in: nfsd xfs libcrc32c virtio_net virtio_pci [ 74.329117] CPU: 0 PID: 2849 Comm: xdp2 Not tainted 4.10.0-rc7+ #499 [ 74.329577] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014 [ 74.330424] task: ffff88007a894000 task.stack: ffffc90004388000 [ 74.330844] RIP: 0010:skb_release_head_state+0x28/0x80 [ 74.331298] RSP: 0018:ffffc9000438b8d0 EFLAGS: 00010206 [ 74.331676] RAX: 0000000000000000 RBX: ffff88007ad96300 RCX: 0000000000000000 [ 74.332217] RDX: ffff88007fc137a8 RSI: ffff88007fc0db28 RDI: 0001bf00000001be [ 74.332758] RBP: ffffc9000438b8d8 R08: 000000000005008f R09: 00000000000005f9 [ 74.333274] R10: ffff88007d001700 R11: ffffffff820a8a4d R12: ffff88007ad96300 [ 74.333787] R13: 0000000000000002 R14: ffff880036604000 R15: 000077ff80000000 [ 74.334308] FS: 00007fc70d8a7b40(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 [ 74.334891] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 74.335314] CR2: 00007fff4144a710 CR3: 000000007ab56000 CR4: 00000000003406f0 [ 74.335830] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 74.336373] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 74.336895] Call Trace: [ 74.337086] skb_release_all+0xd/0x30 [ 74.337356] consume_skb+0x2c/0x90 [ 74.337607] free_unused_bufs+0x1ff/0x270 [virtio_net] [ 74.337988] ? vp_synchronize_vectors+0x3b/0x60 [virtio_pci] [ 74.338398] virtnet_xdp+0x21e/0x440 [virtio_net] [ 74.338741] dev_change_xdp_fd+0x101/0x140 [ 74.339048] do_setlink+0xcf4/0xd20 [ 74.339304] ? symcmp+0xf/0x20 [ 74.339529] ? mls_level_isvalid+0x52/0x60 [ 74.339828] ? mls_range_isvalid+0x43/0x50 [ 74.340135] ? nla_parse+0xa0/0x100 [ 74.340400] rtnl_setlink+0xd4/0x120 [ 74.340664] ? cpumask_next_and+0x30/0x50 [ 74.340966] rtnetlink_rcv_msg+0x7f/0x1f0 [ 74.341259] ? sock_has_perm+0x59/0x60 [ 74.341586] ? napi_consume_skb+0xe2/0x100 [ 74.342010] ? rtnl_newlink+0x890/0x890 [ 74.342435] netlink_rcv_skb+0x92/0xb0 [ 74.342846] rtnetlink_rcv+0x23/0x30 [ 74.343277] netlink_unicast+0x162/0x210 [ 74.343677] netlink_sendmsg+0x2db/0x390 [ 74.343968] sock_sendmsg+0x33/0x40 [ 74.344233] SYSC_sendto+0xee/0x160 [ 74.344482] ? SYSC_bind+0xb0/0xe0 [ 74.344806] ? sock_alloc_file+0x92/0x110 [ 74.345106] ? fd_install+0x20/0x30 [ 74.345360] ? sock_map_fd+0x3f/0x60 [ 74.345586] SyS_sendto+0x9/0x10 [ 74.345790] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 74.346086] RIP: 0033:0x7fc70d1b8f6d [ 74.346312] RSP: 002b:00007fff4144a708 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 74.346785] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fc70d1b8f6d [ 74.347244] RDX: 000000000000002c RSI: 00007fff4144a720 RDI: 0000000000000003 [ 74.347683] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 [ 74.348544] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff4144bd90 [ 74.349082] R13: 0000000000000002 R14: 0000000000000002 R15: 00007fff4144cda0 [ 74.349607] Code: 00 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 58 48 85 ff 74 0e 40 f6 c7 01 74 3d 48 c7 43 58 00 00 00 00 48 8b 7b 68 48 85 ff 74 05 <f0> ff 0f 74 20 48 8b 43 60 48 85 c0 74 14 65 8b 15 f3 ab 8d 7e [ 74.351008] RIP: skb_release_head_state+0x28/0x80 RSP: ffffc9000438b8d0 [ 74.351625] ---[ end trace fe6e19fd11cfc80b ]--- Fixes: 2de2f7f40ef9 ("virtio_net: XDP support for adjust_head") Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-20 06:50:20 +03:00
ret = _virtnet_set_queues(vi, curr_qp);
if (ret)
goto err;
virtio_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
virtio_config_enable(dev);
return 0;
err:
virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
return ret;
}
static int virtnet_xdp_set(struct net_device *dev, struct bpf_prog *prog)
{
unsigned long int max_sz = PAGE_SIZE - sizeof(struct padded_vnet_hdr);
struct virtnet_info *vi = netdev_priv(dev);
struct bpf_prog *old_prog;
virito-net: set queues after reset during xdp_set We set queues before reset which will cause a crash[1]. This is because is_xdp_raw_buffer_queue() depends on the old xdp queue pairs number to do the correct detection. So fix this by - passing xdp queue pairs and current queue pairs to virtnet_reset() - change vi->xdp_qp after reset but before refill, to make sure both free_unused_bufs() and refill can make correct detection of XDP. - remove the duplicated queue pairs setting before virtnet_reset() since we will do it inside virtnet_reset() [1] [ 74.328168] general protection fault: 0000 [#1] SMP [ 74.328625] Modules linked in: nfsd xfs libcrc32c virtio_net virtio_pci [ 74.329117] CPU: 0 PID: 2849 Comm: xdp2 Not tainted 4.10.0-rc7+ #499 [ 74.329577] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014 [ 74.330424] task: ffff88007a894000 task.stack: ffffc90004388000 [ 74.330844] RIP: 0010:skb_release_head_state+0x28/0x80 [ 74.331298] RSP: 0018:ffffc9000438b8d0 EFLAGS: 00010206 [ 74.331676] RAX: 0000000000000000 RBX: ffff88007ad96300 RCX: 0000000000000000 [ 74.332217] RDX: ffff88007fc137a8 RSI: ffff88007fc0db28 RDI: 0001bf00000001be [ 74.332758] RBP: ffffc9000438b8d8 R08: 000000000005008f R09: 00000000000005f9 [ 74.333274] R10: ffff88007d001700 R11: ffffffff820a8a4d R12: ffff88007ad96300 [ 74.333787] R13: 0000000000000002 R14: ffff880036604000 R15: 000077ff80000000 [ 74.334308] FS: 00007fc70d8a7b40(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 [ 74.334891] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 74.335314] CR2: 00007fff4144a710 CR3: 000000007ab56000 CR4: 00000000003406f0 [ 74.335830] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 74.336373] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 74.336895] Call Trace: [ 74.337086] skb_release_all+0xd/0x30 [ 74.337356] consume_skb+0x2c/0x90 [ 74.337607] free_unused_bufs+0x1ff/0x270 [virtio_net] [ 74.337988] ? vp_synchronize_vectors+0x3b/0x60 [virtio_pci] [ 74.338398] virtnet_xdp+0x21e/0x440 [virtio_net] [ 74.338741] dev_change_xdp_fd+0x101/0x140 [ 74.339048] do_setlink+0xcf4/0xd20 [ 74.339304] ? symcmp+0xf/0x20 [ 74.339529] ? mls_level_isvalid+0x52/0x60 [ 74.339828] ? mls_range_isvalid+0x43/0x50 [ 74.340135] ? nla_parse+0xa0/0x100 [ 74.340400] rtnl_setlink+0xd4/0x120 [ 74.340664] ? cpumask_next_and+0x30/0x50 [ 74.340966] rtnetlink_rcv_msg+0x7f/0x1f0 [ 74.341259] ? sock_has_perm+0x59/0x60 [ 74.341586] ? napi_consume_skb+0xe2/0x100 [ 74.342010] ? rtnl_newlink+0x890/0x890 [ 74.342435] netlink_rcv_skb+0x92/0xb0 [ 74.342846] rtnetlink_rcv+0x23/0x30 [ 74.343277] netlink_unicast+0x162/0x210 [ 74.343677] netlink_sendmsg+0x2db/0x390 [ 74.343968] sock_sendmsg+0x33/0x40 [ 74.344233] SYSC_sendto+0xee/0x160 [ 74.344482] ? SYSC_bind+0xb0/0xe0 [ 74.344806] ? sock_alloc_file+0x92/0x110 [ 74.345106] ? fd_install+0x20/0x30 [ 74.345360] ? sock_map_fd+0x3f/0x60 [ 74.345586] SyS_sendto+0x9/0x10 [ 74.345790] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 74.346086] RIP: 0033:0x7fc70d1b8f6d [ 74.346312] RSP: 002b:00007fff4144a708 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 74.346785] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fc70d1b8f6d [ 74.347244] RDX: 000000000000002c RSI: 00007fff4144a720 RDI: 0000000000000003 [ 74.347683] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 [ 74.348544] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff4144bd90 [ 74.349082] R13: 0000000000000002 R14: 0000000000000002 R15: 00007fff4144cda0 [ 74.349607] Code: 00 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 58 48 85 ff 74 0e 40 f6 c7 01 74 3d 48 c7 43 58 00 00 00 00 48 8b 7b 68 48 85 ff 74 05 <f0> ff 0f 74 20 48 8b 43 60 48 85 c0 74 14 65 8b 15 f3 ab 8d 7e [ 74.351008] RIP: skb_release_head_state+0x28/0x80 RSP: ffffc9000438b8d0 [ 74.351625] ---[ end trace fe6e19fd11cfc80b ]--- Fixes: 2de2f7f40ef9 ("virtio_net: XDP support for adjust_head") Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-20 06:50:20 +03:00
u16 xdp_qp = 0, curr_qp;
int i, err;
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO4) ||
virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_TSO6) ||
virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_ECN) ||
virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_UFO)) {
netdev_warn(dev, "can't set XDP while host is implementing LRO, disable LRO first\n");
return -EOPNOTSUPP;
}
if (vi->mergeable_rx_bufs && !vi->any_header_sg) {
netdev_warn(dev, "XDP expects header/data in single page, any_header_sg required\n");
return -EINVAL;
}
if (dev->mtu > max_sz) {
netdev_warn(dev, "XDP requires MTU less than %lu\n", max_sz);
return -EINVAL;
}
curr_qp = vi->curr_queue_pairs - vi->xdp_queue_pairs;
if (prog)
xdp_qp = nr_cpu_ids;
/* XDP requires extra queues for XDP_TX */
if (curr_qp + xdp_qp > vi->max_queue_pairs) {
netdev_warn(dev, "request %i queues but max is %i\n",
curr_qp + xdp_qp, vi->max_queue_pairs);
return -ENOMEM;
}
if (prog) {
prog = bpf_prog_add(prog, vi->max_queue_pairs - 1);
if (IS_ERR(prog))
return PTR_ERR(prog);
}
/* Changing the headroom in buffers is a disruptive operation because
* existing buffers must be flushed and reallocated. This will happen
* when a xdp program is initially added or xdp is disabled by removing
* the xdp program resulting in number of XDP queues changing.
*/
if (vi->xdp_queue_pairs != xdp_qp) {
virito-net: set queues after reset during xdp_set We set queues before reset which will cause a crash[1]. This is because is_xdp_raw_buffer_queue() depends on the old xdp queue pairs number to do the correct detection. So fix this by - passing xdp queue pairs and current queue pairs to virtnet_reset() - change vi->xdp_qp after reset but before refill, to make sure both free_unused_bufs() and refill can make correct detection of XDP. - remove the duplicated queue pairs setting before virtnet_reset() since we will do it inside virtnet_reset() [1] [ 74.328168] general protection fault: 0000 [#1] SMP [ 74.328625] Modules linked in: nfsd xfs libcrc32c virtio_net virtio_pci [ 74.329117] CPU: 0 PID: 2849 Comm: xdp2 Not tainted 4.10.0-rc7+ #499 [ 74.329577] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014 [ 74.330424] task: ffff88007a894000 task.stack: ffffc90004388000 [ 74.330844] RIP: 0010:skb_release_head_state+0x28/0x80 [ 74.331298] RSP: 0018:ffffc9000438b8d0 EFLAGS: 00010206 [ 74.331676] RAX: 0000000000000000 RBX: ffff88007ad96300 RCX: 0000000000000000 [ 74.332217] RDX: ffff88007fc137a8 RSI: ffff88007fc0db28 RDI: 0001bf00000001be [ 74.332758] RBP: ffffc9000438b8d8 R08: 000000000005008f R09: 00000000000005f9 [ 74.333274] R10: ffff88007d001700 R11: ffffffff820a8a4d R12: ffff88007ad96300 [ 74.333787] R13: 0000000000000002 R14: ffff880036604000 R15: 000077ff80000000 [ 74.334308] FS: 00007fc70d8a7b40(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 [ 74.334891] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 74.335314] CR2: 00007fff4144a710 CR3: 000000007ab56000 CR4: 00000000003406f0 [ 74.335830] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 74.336373] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 74.336895] Call Trace: [ 74.337086] skb_release_all+0xd/0x30 [ 74.337356] consume_skb+0x2c/0x90 [ 74.337607] free_unused_bufs+0x1ff/0x270 [virtio_net] [ 74.337988] ? vp_synchronize_vectors+0x3b/0x60 [virtio_pci] [ 74.338398] virtnet_xdp+0x21e/0x440 [virtio_net] [ 74.338741] dev_change_xdp_fd+0x101/0x140 [ 74.339048] do_setlink+0xcf4/0xd20 [ 74.339304] ? symcmp+0xf/0x20 [ 74.339529] ? mls_level_isvalid+0x52/0x60 [ 74.339828] ? mls_range_isvalid+0x43/0x50 [ 74.340135] ? nla_parse+0xa0/0x100 [ 74.340400] rtnl_setlink+0xd4/0x120 [ 74.340664] ? cpumask_next_and+0x30/0x50 [ 74.340966] rtnetlink_rcv_msg+0x7f/0x1f0 [ 74.341259] ? sock_has_perm+0x59/0x60 [ 74.341586] ? napi_consume_skb+0xe2/0x100 [ 74.342010] ? rtnl_newlink+0x890/0x890 [ 74.342435] netlink_rcv_skb+0x92/0xb0 [ 74.342846] rtnetlink_rcv+0x23/0x30 [ 74.343277] netlink_unicast+0x162/0x210 [ 74.343677] netlink_sendmsg+0x2db/0x390 [ 74.343968] sock_sendmsg+0x33/0x40 [ 74.344233] SYSC_sendto+0xee/0x160 [ 74.344482] ? SYSC_bind+0xb0/0xe0 [ 74.344806] ? sock_alloc_file+0x92/0x110 [ 74.345106] ? fd_install+0x20/0x30 [ 74.345360] ? sock_map_fd+0x3f/0x60 [ 74.345586] SyS_sendto+0x9/0x10 [ 74.345790] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 74.346086] RIP: 0033:0x7fc70d1b8f6d [ 74.346312] RSP: 002b:00007fff4144a708 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 74.346785] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fc70d1b8f6d [ 74.347244] RDX: 000000000000002c RSI: 00007fff4144a720 RDI: 0000000000000003 [ 74.347683] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 [ 74.348544] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff4144bd90 [ 74.349082] R13: 0000000000000002 R14: 0000000000000002 R15: 00007fff4144cda0 [ 74.349607] Code: 00 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 58 48 85 ff 74 0e 40 f6 c7 01 74 3d 48 c7 43 58 00 00 00 00 48 8b 7b 68 48 85 ff 74 05 <f0> ff 0f 74 20 48 8b 43 60 48 85 c0 74 14 65 8b 15 f3 ab 8d 7e [ 74.351008] RIP: skb_release_head_state+0x28/0x80 RSP: ffffc9000438b8d0 [ 74.351625] ---[ end trace fe6e19fd11cfc80b ]--- Fixes: 2de2f7f40ef9 ("virtio_net: XDP support for adjust_head") Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-20 06:50:20 +03:00
err = virtnet_reset(vi, curr_qp + xdp_qp, xdp_qp);
if (err) {
dev_warn(&dev->dev, "XDP reset failure.\n");
goto virtio_reset_err;
virito-net: set queues after reset during xdp_set We set queues before reset which will cause a crash[1]. This is because is_xdp_raw_buffer_queue() depends on the old xdp queue pairs number to do the correct detection. So fix this by - passing xdp queue pairs and current queue pairs to virtnet_reset() - change vi->xdp_qp after reset but before refill, to make sure both free_unused_bufs() and refill can make correct detection of XDP. - remove the duplicated queue pairs setting before virtnet_reset() since we will do it inside virtnet_reset() [1] [ 74.328168] general protection fault: 0000 [#1] SMP [ 74.328625] Modules linked in: nfsd xfs libcrc32c virtio_net virtio_pci [ 74.329117] CPU: 0 PID: 2849 Comm: xdp2 Not tainted 4.10.0-rc7+ #499 [ 74.329577] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014 [ 74.330424] task: ffff88007a894000 task.stack: ffffc90004388000 [ 74.330844] RIP: 0010:skb_release_head_state+0x28/0x80 [ 74.331298] RSP: 0018:ffffc9000438b8d0 EFLAGS: 00010206 [ 74.331676] RAX: 0000000000000000 RBX: ffff88007ad96300 RCX: 0000000000000000 [ 74.332217] RDX: ffff88007fc137a8 RSI: ffff88007fc0db28 RDI: 0001bf00000001be [ 74.332758] RBP: ffffc9000438b8d8 R08: 000000000005008f R09: 00000000000005f9 [ 74.333274] R10: ffff88007d001700 R11: ffffffff820a8a4d R12: ffff88007ad96300 [ 74.333787] R13: 0000000000000002 R14: ffff880036604000 R15: 000077ff80000000 [ 74.334308] FS: 00007fc70d8a7b40(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000 [ 74.334891] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 74.335314] CR2: 00007fff4144a710 CR3: 000000007ab56000 CR4: 00000000003406f0 [ 74.335830] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 74.336373] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 74.336895] Call Trace: [ 74.337086] skb_release_all+0xd/0x30 [ 74.337356] consume_skb+0x2c/0x90 [ 74.337607] free_unused_bufs+0x1ff/0x270 [virtio_net] [ 74.337988] ? vp_synchronize_vectors+0x3b/0x60 [virtio_pci] [ 74.338398] virtnet_xdp+0x21e/0x440 [virtio_net] [ 74.338741] dev_change_xdp_fd+0x101/0x140 [ 74.339048] do_setlink+0xcf4/0xd20 [ 74.339304] ? symcmp+0xf/0x20 [ 74.339529] ? mls_level_isvalid+0x52/0x60 [ 74.339828] ? mls_range_isvalid+0x43/0x50 [ 74.340135] ? nla_parse+0xa0/0x100 [ 74.340400] rtnl_setlink+0xd4/0x120 [ 74.340664] ? cpumask_next_and+0x30/0x50 [ 74.340966] rtnetlink_rcv_msg+0x7f/0x1f0 [ 74.341259] ? sock_has_perm+0x59/0x60 [ 74.341586] ? napi_consume_skb+0xe2/0x100 [ 74.342010] ? rtnl_newlink+0x890/0x890 [ 74.342435] netlink_rcv_skb+0x92/0xb0 [ 74.342846] rtnetlink_rcv+0x23/0x30 [ 74.343277] netlink_unicast+0x162/0x210 [ 74.343677] netlink_sendmsg+0x2db/0x390 [ 74.343968] sock_sendmsg+0x33/0x40 [ 74.344233] SYSC_sendto+0xee/0x160 [ 74.344482] ? SYSC_bind+0xb0/0xe0 [ 74.344806] ? sock_alloc_file+0x92/0x110 [ 74.345106] ? fd_install+0x20/0x30 [ 74.345360] ? sock_map_fd+0x3f/0x60 [ 74.345586] SyS_sendto+0x9/0x10 [ 74.345790] entry_SYSCALL_64_fastpath+0x1a/0xa9 [ 74.346086] RIP: 0033:0x7fc70d1b8f6d [ 74.346312] RSP: 002b:00007fff4144a708 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 74.346785] RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fc70d1b8f6d [ 74.347244] RDX: 000000000000002c RSI: 00007fff4144a720 RDI: 0000000000000003 [ 74.347683] RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 [ 74.348544] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff4144bd90 [ 74.349082] R13: 0000000000000002 R14: 0000000000000002 R15: 00007fff4144cda0 [ 74.349607] Code: 00 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 58 48 85 ff 74 0e 40 f6 c7 01 74 3d 48 c7 43 58 00 00 00 00 48 8b 7b 68 48 85 ff 74 05 <f0> ff 0f 74 20 48 8b 43 60 48 85 c0 74 14 65 8b 15 f3 ab 8d 7e [ 74.351008] RIP: skb_release_head_state+0x28/0x80 RSP: ffffc9000438b8d0 [ 74.351625] ---[ end trace fe6e19fd11cfc80b ]--- Fixes: 2de2f7f40ef9 ("virtio_net: XDP support for adjust_head") Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-20 06:50:20 +03:00
}
}
netif_set_real_num_rx_queues(dev, curr_qp + xdp_qp);
for (i = 0; i < vi->max_queue_pairs; i++) {
old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
rcu_assign_pointer(vi->rq[i].xdp_prog, prog);
if (old_prog)
bpf_prog_put(old_prog);
}
return 0;
virtio_reset_err:
/* On reset error do our best to unwind XDP changes inflight and return
* error up to user space for resolution. The underlying reset hung on
* us so not much we can do here.
*/
if (prog)
bpf_prog_sub(prog, vi->max_queue_pairs - 1);
return err;
}
static bool virtnet_xdp_query(struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
int i;
for (i = 0; i < vi->max_queue_pairs; i++) {
if (vi->rq[i].xdp_prog)
return true;
}
return false;
}
static int virtnet_xdp(struct net_device *dev, struct netdev_xdp *xdp)
{
switch (xdp->command) {
case XDP_SETUP_PROG:
return virtnet_xdp_set(dev, xdp->prog);
case XDP_QUERY_PROG:
xdp->prog_attached = virtnet_xdp_query(dev);
return 0;
default:
return -EINVAL;
}
}
static const struct net_device_ops virtnet_netdev = {
.ndo_open = virtnet_open,
.ndo_stop = virtnet_close,
.ndo_start_xmit = start_xmit,
.ndo_validate_addr = eth_validate_addr,
.ndo_set_mac_address = virtnet_set_mac_address,
.ndo_set_rx_mode = virtnet_set_rx_mode,
.ndo_get_stats64 = virtnet_stats,
.ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,
.ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,
#ifdef CONFIG_NET_POLL_CONTROLLER
.ndo_poll_controller = virtnet_netpoll,
#endif
.ndo_xdp = virtnet_xdp,
};
static void virtnet_config_changed_work(struct work_struct *work)
{
struct virtnet_info *vi =
container_of(work, struct virtnet_info, config_work);
u16 v;
if (virtio_cread_feature(vi->vdev, VIRTIO_NET_F_STATUS,
struct virtio_net_config, status, &v) < 0)
return;
if (v & VIRTIO_NET_S_ANNOUNCE) {
netdev_notify_peers(vi->dev);
virtnet_ack_link_announce(vi);
}
/* Ignore unknown (future) status bits */
v &= VIRTIO_NET_S_LINK_UP;
if (vi->status == v)
return;
vi->status = v;
if (vi->status & VIRTIO_NET_S_LINK_UP) {
netif_carrier_on(vi->dev);
netif_tx_wake_all_queues(vi->dev);
} else {
netif_carrier_off(vi->dev);
netif_tx_stop_all_queues(vi->dev);
}
}
static void virtnet_config_changed(struct virtio_device *vdev)
{
struct virtnet_info *vi = vdev->priv;
schedule_work(&vi->config_work);
}
static void virtnet_free_queues(struct virtnet_info *vi)
{
virtio: delete napi structures from netdev before releasing memory free_netdev calls netif_napi_del too, but it's too late, because napi structures are placed on vi->rq. netif_napi_add() is called from virtnet_alloc_queues. general protection fault: 0000 [#1] SMP Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: ip6table_filter ip6_tables iptable_filter ip_tables virtio_balloon pcspkr virtio_net(-) i2c_pii CPU: 1 PID: 347 Comm: rmmod Not tainted 3.13.0-rc2+ #171 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff8800b779c420 ti: ffff8800379e0000 task.ti: ffff8800379e0000 RIP: 0010:[<ffffffff81322e19>] [<ffffffff81322e19>] __list_del_entry+0x29/0xd0 RSP: 0018:ffff8800379e1dd0 EFLAGS: 00010a83 RAX: 6b6b6b6b6b6b6b6b RBX: ffff8800379c2fd0 RCX: dead000000200200 RDX: 6b6b6b6b6b6b6b6b RSI: 0000000000000001 RDI: ffff8800379c2fd0 RBP: ffff8800379e1dd0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff8800379c2f90 R13: ffff880037839160 R14: 0000000000000000 R15: 00000000013352f0 FS: 00007f1400e34740(0000) GS:ffff8800bfb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007f464124c763 CR3: 00000000b68cf000 CR4: 00000000000006e0 Stack: ffff8800379e1df0 ffffffff8155beab 6b6b6b6b6b6b6b2b ffff8800378391c0 ffff8800379e1e18 ffffffff8156499b ffff880037839be0 ffff880037839d20 ffff88003779d3f0 ffff8800379e1e38 ffffffffa003477c ffff88003779d388 Call Trace: [<ffffffff8155beab>] netif_napi_del+0x1b/0x80 [<ffffffff8156499b>] free_netdev+0x8b/0x110 [<ffffffffa003477c>] virtnet_remove+0x7c/0x90 [virtio_net] [<ffffffff813ae323>] virtio_dev_remove+0x23/0x80 [<ffffffff813f62ef>] __device_release_driver+0x7f/0xf0 [<ffffffff813f6ca0>] driver_detach+0xc0/0xd0 [<ffffffff813f5f28>] bus_remove_driver+0x58/0xd0 [<ffffffff813f72ec>] driver_unregister+0x2c/0x50 [<ffffffff813ae65e>] unregister_virtio_driver+0xe/0x10 [<ffffffffa0036942>] virtio_net_driver_exit+0x10/0x6ce [virtio_net] [<ffffffff810d7cf2>] SyS_delete_module+0x172/0x220 [<ffffffff810a732d>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff810f5d4c>] ? __audit_syscall_entry+0x9c/0xf0 [<ffffffff81677f69>] system_call_fastpath+0x16/0x1b Code: 00 00 55 48 8b 17 48 b9 00 01 10 00 00 00 ad de 48 8b 47 08 48 89 e5 48 39 ca 74 29 48 b9 00 02 20 00 00 00 RIP [<ffffffff81322e19>] __list_del_entry+0x29/0xd0 RSP <ffff8800379e1dd0> ---[ end trace d5931cd3f87c9763 ]--- Fixes: 986a4f4d452d (virtio_net: multiqueue support) Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 18:36:21 +04:00
int i;
virtio-net: correctly delete napi hash We don't delete napi from hash list during module exit. This will cause the following panic when doing module load and unload: BUG: unable to handle kernel paging request at 0000004e00000075 IP: [<ffffffff816bd01b>] napi_hash_add+0x6b/0xf0 PGD 3c5d5067 PUD 0 Oops: 0000 [#1] SMP ... Call Trace: [<ffffffffa0a5bfb7>] init_vqs+0x107/0x490 [virtio_net] [<ffffffffa0a5c9f2>] virtnet_probe+0x562/0x791815639d880be [virtio_net] [<ffffffff8139e667>] virtio_dev_probe+0x137/0x200 [<ffffffff814c7f2a>] driver_probe_device+0x7a/0x250 [<ffffffff814c81d3>] __driver_attach+0x93/0xa0 [<ffffffff814c8140>] ? __device_attach+0x40/0x40 [<ffffffff814c6053>] bus_for_each_dev+0x63/0xa0 [<ffffffff814c7a79>] driver_attach+0x19/0x20 [<ffffffff814c76f0>] bus_add_driver+0x170/0x220 [<ffffffffa0a60000>] ? 0xffffffffa0a60000 [<ffffffff814c894f>] driver_register+0x5f/0xf0 [<ffffffff8139e41b>] register_virtio_driver+0x1b/0x30 [<ffffffffa0a60010>] virtio_net_driver_init+0x10/0x12 [virtio_net] This patch fixes this by doing this in virtnet_free_queues(). And also don't delete napi in virtnet_freeze() since it will call virtnet_free_queues() which has already did this. Fixes 91815639d880 ("virtio-net: rx busy polling support") Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-12 08:57:44 +03:00
for (i = 0; i < vi->max_queue_pairs; i++) {
napi_hash_del(&vi->rq[i].napi);
virtio: delete napi structures from netdev before releasing memory free_netdev calls netif_napi_del too, but it's too late, because napi structures are placed on vi->rq. netif_napi_add() is called from virtnet_alloc_queues. general protection fault: 0000 [#1] SMP Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: ip6table_filter ip6_tables iptable_filter ip_tables virtio_balloon pcspkr virtio_net(-) i2c_pii CPU: 1 PID: 347 Comm: rmmod Not tainted 3.13.0-rc2+ #171 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff8800b779c420 ti: ffff8800379e0000 task.ti: ffff8800379e0000 RIP: 0010:[<ffffffff81322e19>] [<ffffffff81322e19>] __list_del_entry+0x29/0xd0 RSP: 0018:ffff8800379e1dd0 EFLAGS: 00010a83 RAX: 6b6b6b6b6b6b6b6b RBX: ffff8800379c2fd0 RCX: dead000000200200 RDX: 6b6b6b6b6b6b6b6b RSI: 0000000000000001 RDI: ffff8800379c2fd0 RBP: ffff8800379e1dd0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff8800379c2f90 R13: ffff880037839160 R14: 0000000000000000 R15: 00000000013352f0 FS: 00007f1400e34740(0000) GS:ffff8800bfb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007f464124c763 CR3: 00000000b68cf000 CR4: 00000000000006e0 Stack: ffff8800379e1df0 ffffffff8155beab 6b6b6b6b6b6b6b2b ffff8800378391c0 ffff8800379e1e18 ffffffff8156499b ffff880037839be0 ffff880037839d20 ffff88003779d3f0 ffff8800379e1e38 ffffffffa003477c ffff88003779d388 Call Trace: [<ffffffff8155beab>] netif_napi_del+0x1b/0x80 [<ffffffff8156499b>] free_netdev+0x8b/0x110 [<ffffffffa003477c>] virtnet_remove+0x7c/0x90 [virtio_net] [<ffffffff813ae323>] virtio_dev_remove+0x23/0x80 [<ffffffff813f62ef>] __device_release_driver+0x7f/0xf0 [<ffffffff813f6ca0>] driver_detach+0xc0/0xd0 [<ffffffff813f5f28>] bus_remove_driver+0x58/0xd0 [<ffffffff813f72ec>] driver_unregister+0x2c/0x50 [<ffffffff813ae65e>] unregister_virtio_driver+0xe/0x10 [<ffffffffa0036942>] virtio_net_driver_exit+0x10/0x6ce [virtio_net] [<ffffffff810d7cf2>] SyS_delete_module+0x172/0x220 [<ffffffff810a732d>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff810f5d4c>] ? __audit_syscall_entry+0x9c/0xf0 [<ffffffff81677f69>] system_call_fastpath+0x16/0x1b Code: 00 00 55 48 8b 17 48 b9 00 01 10 00 00 00 ad de 48 8b 47 08 48 89 e5 48 39 ca 74 29 48 b9 00 02 20 00 00 00 RIP [<ffffffff81322e19>] __list_del_entry+0x29/0xd0 RSP <ffff8800379e1dd0> ---[ end trace d5931cd3f87c9763 ]--- Fixes: 986a4f4d452d (virtio_net: multiqueue support) Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 18:36:21 +04:00
netif_napi_del(&vi->rq[i].napi);
virtio-net: correctly delete napi hash We don't delete napi from hash list during module exit. This will cause the following panic when doing module load and unload: BUG: unable to handle kernel paging request at 0000004e00000075 IP: [<ffffffff816bd01b>] napi_hash_add+0x6b/0xf0 PGD 3c5d5067 PUD 0 Oops: 0000 [#1] SMP ... Call Trace: [<ffffffffa0a5bfb7>] init_vqs+0x107/0x490 [virtio_net] [<ffffffffa0a5c9f2>] virtnet_probe+0x562/0x791815639d880be [virtio_net] [<ffffffff8139e667>] virtio_dev_probe+0x137/0x200 [<ffffffff814c7f2a>] driver_probe_device+0x7a/0x250 [<ffffffff814c81d3>] __driver_attach+0x93/0xa0 [<ffffffff814c8140>] ? __device_attach+0x40/0x40 [<ffffffff814c6053>] bus_for_each_dev+0x63/0xa0 [<ffffffff814c7a79>] driver_attach+0x19/0x20 [<ffffffff814c76f0>] bus_add_driver+0x170/0x220 [<ffffffffa0a60000>] ? 0xffffffffa0a60000 [<ffffffff814c894f>] driver_register+0x5f/0xf0 [<ffffffff8139e41b>] register_virtio_driver+0x1b/0x30 [<ffffffffa0a60010>] virtio_net_driver_init+0x10/0x12 [virtio_net] This patch fixes this by doing this in virtnet_free_queues(). And also don't delete napi in virtnet_freeze() since it will call virtnet_free_queues() which has already did this. Fixes 91815639d880 ("virtio-net: rx busy polling support") Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-12 08:57:44 +03:00
}
virtio: delete napi structures from netdev before releasing memory free_netdev calls netif_napi_del too, but it's too late, because napi structures are placed on vi->rq. netif_napi_add() is called from virtnet_alloc_queues. general protection fault: 0000 [#1] SMP Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: ip6table_filter ip6_tables iptable_filter ip_tables virtio_balloon pcspkr virtio_net(-) i2c_pii CPU: 1 PID: 347 Comm: rmmod Not tainted 3.13.0-rc2+ #171 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff8800b779c420 ti: ffff8800379e0000 task.ti: ffff8800379e0000 RIP: 0010:[<ffffffff81322e19>] [<ffffffff81322e19>] __list_del_entry+0x29/0xd0 RSP: 0018:ffff8800379e1dd0 EFLAGS: 00010a83 RAX: 6b6b6b6b6b6b6b6b RBX: ffff8800379c2fd0 RCX: dead000000200200 RDX: 6b6b6b6b6b6b6b6b RSI: 0000000000000001 RDI: ffff8800379c2fd0 RBP: ffff8800379e1dd0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: ffff8800379c2f90 R13: ffff880037839160 R14: 0000000000000000 R15: 00000000013352f0 FS: 00007f1400e34740(0000) GS:ffff8800bfb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007f464124c763 CR3: 00000000b68cf000 CR4: 00000000000006e0 Stack: ffff8800379e1df0 ffffffff8155beab 6b6b6b6b6b6b6b2b ffff8800378391c0 ffff8800379e1e18 ffffffff8156499b ffff880037839be0 ffff880037839d20 ffff88003779d3f0 ffff8800379e1e38 ffffffffa003477c ffff88003779d388 Call Trace: [<ffffffff8155beab>] netif_napi_del+0x1b/0x80 [<ffffffff8156499b>] free_netdev+0x8b/0x110 [<ffffffffa003477c>] virtnet_remove+0x7c/0x90 [virtio_net] [<ffffffff813ae323>] virtio_dev_remove+0x23/0x80 [<ffffffff813f62ef>] __device_release_driver+0x7f/0xf0 [<ffffffff813f6ca0>] driver_detach+0xc0/0xd0 [<ffffffff813f5f28>] bus_remove_driver+0x58/0xd0 [<ffffffff813f72ec>] driver_unregister+0x2c/0x50 [<ffffffff813ae65e>] unregister_virtio_driver+0xe/0x10 [<ffffffffa0036942>] virtio_net_driver_exit+0x10/0x6ce [virtio_net] [<ffffffff810d7cf2>] SyS_delete_module+0x172/0x220 [<ffffffff810a732d>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff810f5d4c>] ? __audit_syscall_entry+0x9c/0xf0 [<ffffffff81677f69>] system_call_fastpath+0x16/0x1b Code: 00 00 55 48 8b 17 48 b9 00 01 10 00 00 00 ad de 48 8b 47 08 48 89 e5 48 39 ca 74 29 48 b9 00 02 20 00 00 00 RIP [<ffffffff81322e19>] __list_del_entry+0x29/0xd0 RSP <ffff8800379e1dd0> ---[ end trace d5931cd3f87c9763 ]--- Fixes: 986a4f4d452d (virtio_net: multiqueue support) Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 18:36:21 +04:00
/* We called napi_hash_del() before netif_napi_del(),
* we need to respect an RCU grace period before freeing vi->rq
*/
synchronize_net();
kfree(vi->rq);
kfree(vi->sq);
}
static void _free_receive_bufs(struct virtnet_info *vi)
{
struct bpf_prog *old_prog;
int i;
for (i = 0; i < vi->max_queue_pairs; i++) {
while (vi->rq[i].pages)
__free_pages(get_a_page(&vi->rq[i], GFP_KERNEL), 0);
old_prog = rtnl_dereference(vi->rq[i].xdp_prog);
RCU_INIT_POINTER(vi->rq[i].xdp_prog, NULL);
if (old_prog)
bpf_prog_put(old_prog);
}
}
static void free_receive_bufs(struct virtnet_info *vi)
{
rtnl_lock();
_free_receive_bufs(vi);
rtnl_unlock();
}
static void free_receive_page_frags(struct virtnet_info *vi)
{
int i;
for (i = 0; i < vi->max_queue_pairs; i++)
if (vi->rq[i].alloc_frag.page)
put_page(vi->rq[i].alloc_frag.page);
}
static bool is_xdp_raw_buffer_queue(struct virtnet_info *vi, int q)
{
if (q < (vi->curr_queue_pairs - vi->xdp_queue_pairs))
return false;
else if (q < vi->curr_queue_pairs)
return true;
else
return false;
}
static void free_unused_bufs(struct virtnet_info *vi)
{
void *buf;
int i;
for (i = 0; i < vi->max_queue_pairs; i++) {
struct virtqueue *vq = vi->sq[i].vq;
while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
if (!is_xdp_raw_buffer_queue(vi, i))
dev_kfree_skb(buf);
else
put_page(virt_to_head_page(buf));
}
}
for (i = 0; i < vi->max_queue_pairs; i++) {
struct virtqueue *vq = vi->rq[i].vq;
while ((buf = virtqueue_detach_unused_buf(vq)) != NULL) {
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
if (vi->mergeable_rx_bufs) {
unsigned long ctx = (unsigned long)buf;
void *base = mergeable_ctx_to_buf_address(ctx);
put_page(virt_to_head_page(base));
} else if (vi->big_packets) {
virtio-net: determine type of bufs correctly free_unused_bufs must check vi->mergeable_rx_bufs before vi->big_packets, because we use this sequence in other places. Otherwise we allocate buffer of one type, then free it as another type. general protection fault: 0000 [#1] SMP Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: ip6table_filter ip6_tables iptable_filter ip_tables pcspkr virtio_balloon virtio_net(-) i2c_pii CPU: 0 PID: 400 Comm: rmmod Not tainted 3.13.0-rc2+ #170 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 task: ffff8800b6d2a210 ti: ffff8800aed32000 task.ti: ffff8800aed32000 RIP: 0010:[<ffffffffa00345f3>] [<ffffffffa00345f3>] free_unused_bufs+0xc3/0x190 [virtio_net] RSP: 0018:ffff8800aed33dd8 EFLAGS: 00010202 RAX: ffff8800b1fe2c00 RBX: ffff8800b66a7240 RCX: 6b6b6b6b6b6b6b6b RDX: 6b6b6b6b6b6b6b6b RSI: ffff8800b8419a68 RDI: ffff8800b66a1148 RBP: ffff8800aed33e00 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: ffff8800b66a1148 R14: 0000000000000000 R15: 000077ff80000000 FS: 00007fc4f9c4e740(0000) GS:ffff8800bfa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 00007f63f432f000 CR3: 00000000b6538000 CR4: 00000000000006f0 Stack: ffff8800b66a7240 ffff8800b66a7380 ffff8800377bd3f0 0000000000000000 00000000023302f0 ffff8800aed33e18 ffffffffa00346e2 ffff8800b66a7240 ffff8800aed33e38 ffffffffa003474d ffff8800377bd388 ffff8800377bd390 Call Trace: [<ffffffffa00346e2>] remove_vq_common+0x22/0x40 [virtio_net] [<ffffffffa003474d>] virtnet_remove+0x4d/0x90 [virtio_net] [<ffffffff813ae303>] virtio_dev_remove+0x23/0x80 [<ffffffff813f62cf>] __device_release_driver+0x7f/0xf0 [<ffffffff813f6c80>] driver_detach+0xc0/0xd0 [<ffffffff813f5f08>] bus_remove_driver+0x58/0xd0 [<ffffffff813f72cc>] driver_unregister+0x2c/0x50 [<ffffffff813ae63e>] unregister_virtio_driver+0xe/0x10 [<ffffffffa0036852>] virtio_net_driver_exit+0x10/0x7be [virtio_net] [<ffffffff810d7cf2>] SyS_delete_module+0x172/0x220 [<ffffffff810a732d>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff810f5d4c>] ? __audit_syscall_entry+0x9c/0xf0 [<ffffffff81677f69>] system_call_fastpath+0x16/0x1b Code: c0 74 55 0f 1f 44 00 00 80 7b 30 00 74 7a 48 8b 50 30 4c 89 e6 48 03 73 20 48 85 d2 0f 84 bb 00 00 00 66 0f RIP [<ffffffffa00345f3>] free_unused_bufs+0xc3/0x190 [virtio_net] RSP <ffff8800aed33dd8> ---[ end trace edb570ea923cce9c ]--- Fixes: 2613af0ed18a (virtio_net: migrate mergeable rx buffers to page frag allocators) Cc: Michael Dalton <mwdalton@google.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Andrey Vagin <avagin@openvz.org> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-05 18:36:20 +04:00
give_pages(&vi->rq[i], buf);
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
} else {
put_page(virt_to_head_page(buf));
virtio-net: auto-tune mergeable rx buffer size for improved performance Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers are preferred as larger buffers reduce the TCP window due to SKB truesize. However, single-stream workloads with large average packet sizes have higher throughput if larger (e.g., PAGE_SIZE) buffers are used. This commit auto-tunes the mergeable receiver buffer packet size by choosing the packet buffer size based on an EWMA of the recent packet sizes for the receive queue. Packet buffer sizes range from MTU_SIZE + virtio-net header len to PAGE_SIZE. This improves throughput for large packet workloads, as any workload with average packet size >= PAGE_SIZE will use PAGE_SIZE buffers. These optimizations interact positively with recent commit ba275241030c ("virtio-net: coalesce rx frags when possible during rx"), which coalesces adjacent RX SKB fragments in virtio_net. The coalescing optimizations benefit buffers of any size. Benchmarks taken from an average of 5 netperf 30-second TCP_STREAM runs between two QEMU VMs on a single physical machine. Each VM has two VCPUs with all offloads & vhost enabled. All VMs and vhost threads run in a single 4 CPU cgroup cpuset, using cgroups to ensure that other processes in the system will not be scheduled on the benchmark CPUs. Trunk includes SKB rx frag coalescing. net-next w/ virtio_net before 2613af0ed18a (PAGE_SIZE bufs): 14642.85Gb/s net-next (MTU-size bufs): 13170.01Gb/s net-next + auto-tune: 14555.94Gb/s Jason Wang also reported a throughput increase on mlx4 from 22Gb/s using MTU-sized buffers to about 26Gb/s using auto-tuning. Signed-off-by: Michael Dalton <mwdalton@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-17 10:23:27 +04:00
}
}
}
}
static void virtnet_del_vqs(struct virtnet_info *vi)
{
struct virtio_device *vdev = vi->vdev;
virtnet_clean_affinity(vi, -1);
vdev->config->del_vqs(vdev);
virtnet_free_queues(vi);
}
static int virtnet_find_vqs(struct virtnet_info *vi)
{
vq_callback_t **callbacks;
struct virtqueue **vqs;
int ret = -ENOMEM;
int i, total_vqs;
const char **names;
/* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
* possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
* possible control vq.
*/
total_vqs = vi->max_queue_pairs * 2 +
virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
/* Allocate space for find_vqs parameters */
vqs = kzalloc(total_vqs * sizeof(*vqs), GFP_KERNEL);
if (!vqs)
goto err_vq;
callbacks = kmalloc(total_vqs * sizeof(*callbacks), GFP_KERNEL);
if (!callbacks)
goto err_callback;
names = kmalloc(total_vqs * sizeof(*names), GFP_KERNEL);
if (!names)
goto err_names;
/* Parameters for control virtqueue, if any */
if (vi->has_cvq) {
callbacks[total_vqs - 1] = NULL;
names[total_vqs - 1] = "control";
}
/* Allocate/initialize parameters for send/receive virtqueues */
for (i = 0; i < vi->max_queue_pairs; i++) {
callbacks[rxq2vq(i)] = skb_recv_done;
callbacks[txq2vq(i)] = skb_xmit_done;
sprintf(vi->rq[i].name, "input.%d", i);
sprintf(vi->sq[i].name, "output.%d", i);
names[rxq2vq(i)] = vi->rq[i].name;
names[txq2vq(i)] = vi->sq[i].name;
}
ret = vi->vdev->config->find_vqs(vi->vdev, total_vqs, vqs, callbacks,
names, NULL);
if (ret)
goto err_find;
if (vi->has_cvq) {
vi->cvq = vqs[total_vqs - 1];
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
}
for (i = 0; i < vi->max_queue_pairs; i++) {
vi->rq[i].vq = vqs[rxq2vq(i)];
vi->sq[i].vq = vqs[txq2vq(i)];
}
kfree(names);
kfree(callbacks);
kfree(vqs);
return 0;
err_find:
kfree(names);
err_names:
kfree(callbacks);
err_callback:
kfree(vqs);
err_vq:
return ret;
}
static int virtnet_alloc_queues(struct virtnet_info *vi)
{
int i;
vi->sq = kzalloc(sizeof(*vi->sq) * vi->max_queue_pairs, GFP_KERNEL);
if (!vi->sq)
goto err_sq;
vi->rq = kzalloc(sizeof(*vi->rq) * vi->max_queue_pairs, GFP_KERNEL);
if (!vi->rq)
goto err_rq;
INIT_DELAYED_WORK(&vi->refill, refill_work);
for (i = 0; i < vi->max_queue_pairs; i++) {
vi->rq[i].pages = NULL;
netif_napi_add(vi->dev, &vi->rq[i].napi, virtnet_poll,
napi_weight);
sg_init_table(vi->rq[i].sg, ARRAY_SIZE(vi->rq[i].sg));
ewma_pkt_len_init(&vi->rq[i].mrg_avg_pkt_len);
sg_init_table(vi->sq[i].sg, ARRAY_SIZE(vi->sq[i].sg));
}
return 0;
err_rq:
kfree(vi->sq);
err_sq:
return -ENOMEM;
}
static int init_vqs(struct virtnet_info *vi)
{
int ret;
/* Allocate send & receive queues */
ret = virtnet_alloc_queues(vi);
if (ret)
goto err;
ret = virtnet_find_vqs(vi);
if (ret)
goto err_free;
get_online_cpus();
virtnet_set_affinity(vi);
put_online_cpus();
return 0;
err_free:
virtnet_free_queues(vi);
err:
return ret;
}
#ifdef CONFIG_SYSFS
static ssize_t mergeable_rx_buffer_size_show(struct netdev_rx_queue *queue,
struct rx_queue_attribute *attribute, char *buf)
{
struct virtnet_info *vi = netdev_priv(queue->dev);
unsigned int queue_index = get_netdev_rx_queue_index(queue);
struct ewma_pkt_len *avg;
BUG_ON(queue_index >= vi->max_queue_pairs);
avg = &vi->rq[queue_index].mrg_avg_pkt_len;
return sprintf(buf, "%u\n", get_mergeable_buf_len(avg));
}
static struct rx_queue_attribute mergeable_rx_buffer_size_attribute =
__ATTR_RO(mergeable_rx_buffer_size);
static struct attribute *virtio_net_mrg_rx_attrs[] = {
&mergeable_rx_buffer_size_attribute.attr,
NULL
};
static const struct attribute_group virtio_net_mrg_rx_group = {
.name = "virtio_net",
.attrs = virtio_net_mrg_rx_attrs
};
#endif
static bool virtnet_fail_on_feature(struct virtio_device *vdev,
unsigned int fbit,
const char *fname, const char *dname)
{
if (!virtio_has_feature(vdev, fbit))
return false;
dev_err(&vdev->dev, "device advertises feature %s but not %s",
fname, dname);
return true;
}
#define VIRTNET_FAIL_ON(vdev, fbit, dbit) \
virtnet_fail_on_feature(vdev, fbit, #fbit, dbit)
static bool virtnet_validate_features(struct virtio_device *vdev)
{
if (!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ) &&
(VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_RX,
"VIRTIO_NET_F_CTRL_VQ") ||
VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_VLAN,
"VIRTIO_NET_F_CTRL_VQ") ||
VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_GUEST_ANNOUNCE,
"VIRTIO_NET_F_CTRL_VQ") ||
VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_MQ, "VIRTIO_NET_F_CTRL_VQ") ||
VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
"VIRTIO_NET_F_CTRL_VQ"))) {
return false;
}
return true;
}
#define MIN_MTU ETH_MIN_MTU
#define MAX_MTU ETH_MAX_MTU
static int virtnet_validate(struct virtio_device *vdev)
{
if (!vdev->config->get) {
dev_err(&vdev->dev, "%s failure: config access disabled\n",
__func__);
return -EINVAL;
}
if (!virtnet_validate_features(vdev))
return -EINVAL;
if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
int mtu = virtio_cread16(vdev,
offsetof(struct virtio_net_config,
mtu));
if (mtu < MIN_MTU)
__virtio_clear_bit(vdev, VIRTIO_NET_F_MTU);
}
return 0;
}
static int virtnet_probe(struct virtio_device *vdev)
{
int i, err;
struct net_device *dev;
struct virtnet_info *vi;
u16 max_queue_pairs;
int mtu;
/* Find if host supports multiqueue virtio_net device */
err = virtio_cread_feature(vdev, VIRTIO_NET_F_MQ,
struct virtio_net_config,
max_virtqueue_pairs, &max_queue_pairs);
/* We need at least 2 queue's */
if (err || max_queue_pairs < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
max_queue_pairs > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
!virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
max_queue_pairs = 1;
/* Allocate ourselves a network device with room for our info */
dev = alloc_etherdev_mq(sizeof(struct virtnet_info), max_queue_pairs);
if (!dev)
return -ENOMEM;
/* Set up network device as normal. */
dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
dev->netdev_ops = &virtnet_netdev;
dev->features = NETIF_F_HIGHDMA;
dev->ethtool_ops = &virtnet_ethtool_ops;
SET_NETDEV_DEV(dev, &vdev->dev);
/* Do we support "hardware" checksums? */
if (virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
/* This opens up the world of extra features. */
dev->hw_features |= NETIF_F_HW_CSUM | NETIF_F_SG;
if (csum)
dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
if (virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
dev->hw_features |= NETIF_F_TSO | NETIF_F_UFO
| NETIF_F_TSO_ECN | NETIF_F_TSO6;
}
/* Individual feature bits: what can host handle? */
if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
dev->hw_features |= NETIF_F_TSO;
if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
dev->hw_features |= NETIF_F_TSO6;
if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
dev->hw_features |= NETIF_F_TSO_ECN;
if (virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
dev->hw_features |= NETIF_F_UFO;
dev->features |= NETIF_F_GSO_ROBUST;
if (gso)
dev->features |= dev->hw_features & (NETIF_F_ALL_TSO|NETIF_F_UFO);
/* (!csum && gso) case will be fixed by register_netdev() */
}
if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM))
dev->features |= NETIF_F_RXCSUM;
dev->vlan_features = dev->features;
/* MTU range: 68 - 65535 */
dev->min_mtu = MIN_MTU;
dev->max_mtu = MAX_MTU;
/* Configuration may specify what MAC to use. Otherwise random. */
if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
virtio_cread_bytes(vdev,
offsetof(struct virtio_net_config, mac),
dev->dev_addr, dev->addr_len);
else
eth_hw_addr_random(dev);
/* Set up our device-specific information */
vi = netdev_priv(dev);
vi->dev = dev;
vi->vdev = vdev;
vdev->priv = vi;
vi->stats = alloc_percpu(struct virtnet_stats);
err = -ENOMEM;
if (vi->stats == NULL)
goto free;
net: Explicitly initialize u64_stats_sync structures for lockdep In order to enable lockdep on seqcount/seqlock structures, we must explicitly initialize any locks. The u64_stats_sync structure, uses a seqcount, and thus we need to introduce a u64_stats_init() function and use it to initialize the structure. This unfortunately adds a lot of fairly trivial initialization code to a number of drivers. But the benefit of ensuring correctness makes this worth while. Because these changes are required for lockdep to be enabled, and the changes are quite trivial, I've not yet split this patch out into 30-some separate patches, as I figured it would be better to get the various maintainers thoughts on how to best merge this change along with the seqcount lockdep enablement. Feedback would be appreciated! Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: James Morris <jmorris@namei.org> Cc: Jesse Gross <jesse@nicira.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Mirko Lindner <mlindner@marvell.com> Cc: Patrick McHardy <kaber@trash.net> Cc: Roger Luethi <rl@hellgate.ch> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Simon Horman <horms@verge.net.au> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Cc: Wensong Zhang <wensong@linux-vs.org> Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/1381186321-4906-2-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-10-08 02:51:58 +04:00
for_each_possible_cpu(i) {
struct virtnet_stats *virtnet_stats;
virtnet_stats = per_cpu_ptr(vi->stats, i);
u64_stats_init(&virtnet_stats->tx_syncp);
u64_stats_init(&virtnet_stats->rx_syncp);
}
INIT_WORK(&vi->config_work, virtnet_config_changed_work);
/* If we can receive ANY GSO packets, we must allocate large ones. */
if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6) ||
virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_ECN) ||
virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_UFO))
vi->big_packets = true;
virtio_net: VIRTIO_NET_F_MSG_RXBUF (imprive rcv buffer allocation) If segmentation offload is enabled by the host, we currently allocate maximum sized packet buffers and pass them to the host. This uses up 20 ring entries, allowing us to supply only 20 packet buffers to the host with a 256 entry ring. This is a huge overhead when receiving small packets, and is most keenly felt when receiving MTU sized packets from off-host. The VIRTIO_NET_F_MRG_RXBUF feature flag is set by hosts which support using receive buffers which are smaller than the maximum packet size. In order to transfer large packets to the guest, the host merges together multiple receive buffers to form a larger logical buffer. The number of merged buffers is returned to the guest via a field in the virtio_net_hdr. Make use of this support by supplying single page receive buffers to the host. On receive, we extract the virtio_net_hdr, copy 128 bytes of the payload to the skb's linear data buffer and adjust the fragment offset to point to the remaining data. This ensures proper alignment and allows us to not use any paged data for small packets. If the payload occupies multiple pages, we simply append those pages as fragments and free the associated skbs. This scheme allows us to be efficient in our use of ring entries while still supporting large packets. Benchmarking using netperf from an external machine to a guest over a 10Gb/s network shows a 100% improvement from ~1Gb/s to ~2Gb/s. With a local host->guest benchmark with GSO disabled on the host side, throughput was seen to increase from 700Mb/s to 1.7Gb/s. Based on a patch from Herbert Xu. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv) Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-17 09:41:34 +03:00
if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
vi->mergeable_rx_bufs = true;
if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
else
vi->hdr_len = sizeof(struct virtio_net_hdr);
if (virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT) ||
virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
vi->any_header_sg = true;
if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_VQ))
vi->has_cvq = true;
if (virtio_has_feature(vdev, VIRTIO_NET_F_MTU)) {
mtu = virtio_cread16(vdev,
offsetof(struct virtio_net_config,
mtu));
if (mtu < dev->min_mtu) {
/* Should never trigger: MTU was previously validated
* in virtnet_validate.
*/
dev_err(&vdev->dev, "device MTU appears to have changed "
"it is now %d < %d", mtu, dev->min_mtu);
goto free_stats;
}
dev->mtu = mtu;
dev->max_mtu = mtu;
/* TODO: size buffers correctly in this case. */
if (dev->mtu > ETH_DATA_LEN)
vi->big_packets = true;
}
if (vi->any_header_sg)
dev->needed_headroom = vi->hdr_len;
virtio-net: Set needed_headroom for virtio-net when VIRTIO_F_ANY_LAYOUT is true This is a small supplement for commit e7428e95a06fb516fac1308bd0e176e27c0b9287 ("virtio-net: put virtio-net header inline with data"). TCP packages have enough room to put virtio-net header in, but UDP packages do not. By setting dev->needed_headroom for virtio-net device, UDP packages could have enough room. For UDP packages, sk_buff is alloced in fun __ip_append_data. The size is "alloclen + hh_len + 15", and "hh_len = LL_RESERVED_SPACE(rt-dst.dev);". The Macro is defined as follows: #define LL_RESERVED_SPACE(dev) \ ((((dev)->hard_header_len+(dev)->needed_headroom)\ &~(HH_DATA_MOD - 1)) + HH_DATA_MOD) By default, for UDP packages, after skb is allocated, only 16 bytes reserved. And 2 bytes remained after mac header is set. That is not enough to put virtio-net header in. If we set dev->needed_headroom to 12 or 10 (according to mergeable_rx_bufs is on or off ), more room can be reserved. Then there is enough room for UDP packages to put the header in. test result list as below: guest and host: suse11sp3, netperf, intel 2.4GHz +-------+---------+---------+---------+---------+ | | old | new | +-------+---------+---------+---------+---------+ | UDP | Gbit/s | pps | Gbit/s | pps | | 64 | 0.57 | 692232 | 0.61 | 742420 | | 256 | 1.60 | 686860 | 1.71 | 733331 | | 512 | 2.92 | 674576 | 3.07 | 710446 | | 1024 | 4.99 | 598977 | 5.17 | 620821 | | 1460 | 5.68 | 483757 | 7.16 | 610519 | | 4096 | 6.98 | 637468 | 7.21 | 658471 | +-------+---------+---------+---------+---------+ Signed-off-by: Zhang Jie <zhangjie14@huawei.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-29 14:43:22 +04:00
/* Enable multiqueue by default */
if (num_online_cpus() >= max_queue_pairs)
vi->curr_queue_pairs = max_queue_pairs;
else
vi->curr_queue_pairs = num_online_cpus();
vi->max_queue_pairs = max_queue_pairs;
/* Allocate/initialize the rx/tx queues, and invoke find_vqs */
err = init_vqs(vi);
if (err)
goto free_stats;
#ifdef CONFIG_SYSFS
if (vi->mergeable_rx_bufs)
dev->sysfs_rx_queue_group = &virtio_net_mrg_rx_group;
#endif
netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
virtnet_init_settings(dev);
err = register_netdev(dev);
if (err) {
pr_debug("virtio_net: registering device failed\n");
goto free_vqs;
}
virtio_device_ready(vdev);
err = virtnet_cpu_notif_add(vi);
if (err) {
pr_debug("virtio_net: registering cpu notifier failed\n");
goto free_unregister_netdev;
}
virtnet_set_queues(vi, vi->curr_queue_pairs);
/* Assume link up if device can't report link status,
otherwise get link status from config. */
if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
netif_carrier_off(dev);
schedule_work(&vi->config_work);
} else {
vi->status = VIRTIO_NET_S_LINK_UP;
netif_carrier_on(dev);
}
pr_debug("virtnet: registered device %s with %d RX and TX vq's\n",
dev->name, max_queue_pairs);
return 0;
free_unregister_netdev:
vi->vdev->config->reset(vdev);
unregister_netdev(dev);
free_vqs:
cancel_delayed_work_sync(&vi->refill);
free_receive_page_frags(vi);
virtnet_del_vqs(vi);
free_stats:
free_percpu(vi->stats);
free:
free_netdev(dev);
return err;
}
static void _remove_vq_common(struct virtnet_info *vi)
{
vi->vdev->config->reset(vi->vdev);
free_unused_bufs(vi);
_free_receive_bufs(vi);
free_receive_page_frags(vi);
virtnet_del_vqs(vi);
}
static void remove_vq_common(struct virtnet_info *vi)
{
vi->vdev->config->reset(vi->vdev);
/* Free unused buffers in both send and recv, if any. */
free_unused_bufs(vi);
free_receive_bufs(vi);
free_receive_page_frags(vi);
virtnet_del_vqs(vi);
}
static void virtnet_remove(struct virtio_device *vdev)
{
struct virtnet_info *vi = vdev->priv;
virtnet_cpu_notif_remove(vi);
/* Make sure no work handler is accessing the device. */
flush_work(&vi->config_work);
unregister_netdev(vi->dev);
remove_vq_common(vi);
free_percpu(vi->stats);
free_netdev(vi->dev);
}
#ifdef CONFIG_PM_SLEEP
static int virtnet_freeze(struct virtio_device *vdev)
{
struct virtnet_info *vi = vdev->priv;
virtnet_cpu_notif_remove(vi);
virtnet_freeze_down(vdev);
remove_vq_common(vi);
return 0;
}
static int virtnet_restore(struct virtio_device *vdev)
{
struct virtnet_info *vi = vdev->priv;
int err;
err = virtnet_restore_up(vdev);
if (err)
return err;
virtnet_set_queues(vi, vi->curr_queue_pairs);
err = virtnet_cpu_notif_add(vi);
virtio-net: correctly handle cpu hotplug notifier during resuming commit 3ab098df35f8b98b6553edc2e40234af512ba877 (virtio-net: don't respond to cpu hotplug notifier if we're not ready) tries to bypass the cpu hotplug notifier by checking the config_enable and does nothing is it was false. So it need to try to hold the config_lock mutex which may happen in atomic environment which leads the following warnings: [ 622.944441] CPU0 attaching NULL sched-domain. [ 622.944446] CPU1 attaching NULL sched-domain. [ 622.944485] CPU0 attaching NULL sched-domain. [ 622.950795] BUG: sleeping function called from invalid context at kernel/mutex.c:616 [ 622.950796] in_atomic(): 1, irqs_disabled(): 1, pid: 10, name: migration/1 [ 622.950796] no locks held by migration/1/10. [ 622.950798] CPU: 1 PID: 10 Comm: migration/1 Not tainted 3.12.0-rc5-wl-01249-gb91e82d #317 [ 622.950799] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 622.950802] 0000000000000000 ffff88001d42dba0 ffffffff81a32f22 ffff88001bfb9c70 [ 622.950803] ffff88001d42dbb0 ffffffff810edb02 ffff88001d42dc38 ffffffff81a396ed [ 622.950805] 0000000000000046 ffff88001d42dbe8 ffffffff810e861d 0000000000000000 [ 622.950805] Call Trace: [ 622.950810] [<ffffffff81a32f22>] dump_stack+0x54/0x74 [ 622.950815] [<ffffffff810edb02>] __might_sleep+0x112/0x114 [ 622.950817] [<ffffffff81a396ed>] mutex_lock_nested+0x3c/0x3c6 [ 622.950818] [<ffffffff810e861d>] ? up+0x39/0x3e [ 622.950821] [<ffffffff8153ea7c>] ? acpi_os_signal_semaphore+0x21/0x2d [ 622.950824] [<ffffffff81565ed1>] ? acpi_ut_release_mutex+0x5e/0x62 [ 622.950828] [<ffffffff816d04ec>] virtnet_cpu_callback+0x33/0x87 [ 622.950830] [<ffffffff81a42576>] notifier_call_chain+0x3c/0x5e [ 622.950832] [<ffffffff810e86a8>] __raw_notifier_call_chain+0xe/0x10 [ 622.950835] [<ffffffff810c5556>] __cpu_notify+0x20/0x37 [ 622.950836] [<ffffffff810c5580>] cpu_notify+0x13/0x15 [ 622.950838] [<ffffffff81a237cd>] take_cpu_down+0x27/0x3a [ 622.950841] [<ffffffff81136289>] stop_machine_cpu_stop+0x93/0xf1 [ 622.950842] [<ffffffff81136167>] cpu_stopper_thread+0xa0/0x12f [ 622.950844] [<ffffffff811361f6>] ? cpu_stopper_thread+0x12f/0x12f [ 622.950847] [<ffffffff81119710>] ? lock_release_holdtime.part.7+0xa3/0xa8 [ 622.950848] [<ffffffff81135e4b>] ? cpu_stop_should_run+0x3f/0x47 [ 622.950850] [<ffffffff810ea9b0>] smpboot_thread_fn+0x1c5/0x1e3 [ 622.950852] [<ffffffff810ea7eb>] ? lg_global_unlock+0x67/0x67 [ 622.950854] [<ffffffff810e36b7>] kthread+0xd8/0xe0 [ 622.950857] [<ffffffff81a3bfad>] ? wait_for_common+0x12f/0x164 [ 622.950859] [<ffffffff810e35df>] ? kthread_create_on_node+0x124/0x124 [ 622.950861] [<ffffffff81a45ffc>] ret_from_fork+0x7c/0xb0 [ 622.950862] [<ffffffff810e35df>] ? kthread_create_on_node+0x124/0x124 [ 622.950876] smpboot: CPU 1 is now offline [ 623.194556] SMP alternatives: lockdep: fixing up alternatives [ 623.194559] smpboot: Booting Node 0 Processor 1 APIC 0x1 ... A correct fix is to unregister the hotcpu notifier during restore and register a new one in resume. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Tested-by: Fengguang Wu <fengguang.wu@intel.com> Cc: Wanlong Gao <gaowanlong@cn.fujitsu.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-29 11:11:07 +04:00
if (err)
return err;
return 0;
}
#endif
static struct virtio_device_id id_table[] = {
{ VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
{ 0 },
};
#define VIRTNET_FEATURES \
VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GUEST_CSUM, \
VIRTIO_NET_F_MAC, \
VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6, \
VIRTIO_NET_F_HOST_ECN, VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, \
VIRTIO_NET_F_GUEST_ECN, VIRTIO_NET_F_GUEST_UFO, \
VIRTIO_NET_F_MRG_RXBUF, VIRTIO_NET_F_STATUS, VIRTIO_NET_F_CTRL_VQ, \
VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \
VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \
VIRTIO_NET_F_CTRL_MAC_ADDR, \
VIRTIO_NET_F_MTU
static unsigned int features[] = {
VIRTNET_FEATURES,
};
static unsigned int features_legacy[] = {
VIRTNET_FEATURES,
VIRTIO_NET_F_GSO,
VIRTIO_F_ANY_LAYOUT,
};
static struct virtio_driver virtio_net_driver = {
.feature_table = features,
.feature_table_size = ARRAY_SIZE(features),
.feature_table_legacy = features_legacy,
.feature_table_size_legacy = ARRAY_SIZE(features_legacy),
.driver.name = KBUILD_MODNAME,
.driver.owner = THIS_MODULE,
.id_table = id_table,
.validate = virtnet_validate,
.probe = virtnet_probe,
.remove = virtnet_remove,
.config_changed = virtnet_config_changed,
#ifdef CONFIG_PM_SLEEP
.freeze = virtnet_freeze,
.restore = virtnet_restore,
#endif
};
static __init int virtio_net_driver_init(void)
{
int ret;
ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "virtio/net:online",
virtnet_cpu_online,
virtnet_cpu_down_prep);
if (ret < 0)
goto out;
virtionet_online = ret;
ret = cpuhp_setup_state_multi(CPUHP_VIRT_NET_DEAD, "virtio/net:dead",
NULL, virtnet_cpu_dead);
if (ret)
goto err_dead;
ret = register_virtio_driver(&virtio_net_driver);
if (ret)
goto err_virtio;
return 0;
err_virtio:
cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
err_dead:
cpuhp_remove_multi_state(virtionet_online);
out:
return ret;
}
module_init(virtio_net_driver_init);
static __exit void virtio_net_driver_exit(void)
{
cpuhp_remove_multi_state(CPUHP_VIRT_NET_DEAD);
cpuhp_remove_multi_state(virtionet_online);
unregister_virtio_driver(&virtio_net_driver);
}
module_exit(virtio_net_driver_exit);
MODULE_DEVICE_TABLE(virtio, id_table);
MODULE_DESCRIPTION("Virtio network driver");
MODULE_LICENSE("GPL");