commit 2f53384424 (tcp: allow splice() to build full TSO packets) added
a regression for splice() calls using SPLICE_F_MORE.
We need to call tcp_flush() at the end of the last page processed in
tcp_sendpages(), or else transmits can be deferred and future sends
stall.
Add a new internal flag, MSG_SENDPAGE_NOTLAST, acting like MSG_MORE, but
with different semantic.
For all sendpage() providers, its a transparent change. Only
sock_sendpage() and tcp_sendpages() can differentiate the two different
flags provided by pipe_to_sendpage()
Reported-by: Tom Herbert <therbert@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: H.K. Jerry Chu <hkchu@google.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail>com>
Signed-off-by: David S. Miller <davem@davemloft.net>
vmsplice()/splice(pipe, socket) call do_tcp_sendpages() one page at a
time, adding at most 4096 bytes to an skb. (assuming PAGE_SIZE=4096)
The call to tcp_push() at the end of do_tcp_sendpages() forces an
immediate xmit when pipe is not already filled, and tso_fragment() try
to split these skb to MSS multiples.
4096 bytes are usually split in a skb with 2 MSS, and a remaining
sub-mss skb (assuming MTU=1500)
This makes slow start suboptimal because many small frames are sent to
qdisc/driver layers instead of big ones (constrained by cwnd and packets
in flight of course)
In fact, applications using sendmsg() (adding an additional memory copy)
instead of vmsplice()/splice()/sendfile() are a bit faster because of
this anomaly, especially if serving small files in environments with
large initial [c]wnd.
Call tcp_push() only if MSG_MORE is not set in the flags parameter.
This bit is automatically provided by splice() internals but for the
last page, or on all pages if user specified SPLICE_F_MORE splice()
flag.
In some workloads, this can reduce number of sent logical packets by an
order of magnitude, making zero-copy TCP actually faster than
one-copy :)
Reported-by: Tom Herbert <therbert@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: H.K. Jerry Chu <hkchu@google.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail>com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Provide device string properly for USB i2400m wimax devices, also
don't OOPS when providing firmware string. From Phil Sutter.
2) Add support for sh_eth SH7734 chips, from Nobuhiro Iwamatsu.
3) Add another device ID to USB zaurus driver, from Guan Xin.
4) Loop index start in pool vector iterator is wrong causing MAC to not
get configured in bnx2x driver, fix from Dmitry Kravkov.
5) EQL driver assumes HZ=100, fix from Eric Dumazet.
6) Now that skb_add_rx_frag() can specify the truesize increment
separately, do so in f_phonet and cdc_phonet, also from Eric
Dumazet.
7) virtio_net accidently uses net_ratelimit() not only on the kernel
warning but also the statistic bump, fix from Rick Jones.
8) ip_route_input_mc() uses fixed init_net namespace, oops, use
dev_net(dev) instead. Fix from Benjamin LaHaise.
9) dev_forward_skb() needs to clear the incoming interface index of the
SKB so that it looks like a new incoming packet, also from Benjamin
LaHaise.
10) iwlwifi mistakenly initializes a channel entry as 2GHZ instead of
5GHZ, fix from Stanislav Yakovlev.
11) Missing kmalloc() return value checks in orinoco, from Santosh
Nayak.
12) ath9k doesn't check for HT capabilities in the right way, it is
checking ht_supported instead of the ATH9K_HW_CAP_HT flag. Fix from
Sujith Manoharan.
13) Fix x86 BPF JIT emission of 16-bit immediate field of AND
instructions, from Feiran Zhuang.
14) Avoid infinite loop in GARP code when registering sysfs entries.
From David Ward.
15) rose protocol uses memcpy instead of memcmp in a device address
comparison, oops. Fix from Daniel Borkmann.
16) Fix build of lpc_eth due to dev_hw_addr_rancom() interface being
renamed to eth_hw_addr_random(). From Roland Stigge.
17) Make ipv6 RTM_GETROUTE interpret RTA_IIF attribute the same way
that ipv4 does. Fix from Shmulik Ladkani.
18) via-rhine has an inverted bit test, causing suspend/resume
regressions. Fix from Andreas Mohr.
19) RIONET assumes 4K page size, fix from Akinobu Mita.
20) Initialization of imask register in sky2 is buggy, because bits are
"or'd" into an uninitialized local variable. Fix from Lino
Sanfilippo.
21) Fix FCOE checksum offload handling, from Yi Zou.
22) Fix VLAN processing regression in e1000, from Jiri Pirko.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (52 commits)
sky2: dont overwrite settings for PHY Quick link
tg3: Fix 5717 serdes powerdown problem
net: usb: cdc_eem: fix mtu
net: sh_eth: fix endian check for architecture independent
usb/rtl8150 : Remove duplicated definitions
rionet: fix page allocation order of rionet_active
via-rhine: fix wait-bit inversion.
ipv6: Fix RTM_GETROUTE's interpretation of RTA_IIF to be consistent with ipv4
net: lpc_eth: Fix rename of dev_hw_addr_random
net/netfilter/nfnetlink_acct.c: use linux/atomic.h
rose_dev: fix memcpy-bug in rose_set_mac_address
Fix non TBI PHY access; a bad merge undid bug fix in a previous commit.
net/garp: avoid infinite loop if attribute already exists
x86 bpf_jit: fix a bug in emitting the 16-bit immediate operand of AND
bonding: emit event when bonding changes MAC
mac80211: fix oper channel timestamp updation
ath9k: Use HW HT capabilites properly
MAINTAINERS: adding maintainer for ipw2x00
net: orinoco: add error handling for failed kmalloc().
net/wireless: ipw2x00: fix a typo in wiphy struct initilization
...
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Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system
Pull "Disintegrate and delete asm/system.h" from David Howells:
"Here are a bunch of patches to disintegrate asm/system.h into a set of
separate bits to relieve the problem of circular inclusion
dependencies.
I've built all the working defconfigs from all the arches that I can
and made sure that they don't break.
The reason for these patches is that I recently encountered a circular
dependency problem that came about when I produced some patches to
optimise get_order() by rewriting it to use ilog2().
This uses bitops - and on the SH arch asm/bitops.h drags in
asm-generic/get_order.h by a circuituous route involving asm/system.h.
The main difficulty seems to be asm/system.h. It holds a number of
low level bits with no/few dependencies that are commonly used (eg.
memory barriers) and a number of bits with more dependencies that
aren't used in many places (eg. switch_to()).
These patches break asm/system.h up into the following core pieces:
(1) asm/barrier.h
Move memory barriers here. This already done for MIPS and Alpha.
(2) asm/switch_to.h
Move switch_to() and related stuff here.
(3) asm/exec.h
Move arch_align_stack() here. Other process execution related bits
could perhaps go here from asm/processor.h.
(4) asm/cmpxchg.h
Move xchg() and cmpxchg() here as they're full word atomic ops and
frequently used by atomic_xchg() and atomic_cmpxchg().
(5) asm/bug.h
Move die() and related bits.
(6) asm/auxvec.h
Move AT_VECTOR_SIZE_ARCH here.
Other arch headers are created as needed on a per-arch basis."
Fixed up some conflicts from other header file cleanups and moving code
around that has happened in the meantime, so David's testing is somewhat
weakened by that. We'll find out anything that got broken and fix it..
* tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits)
Delete all instances of asm/system.h
Remove all #inclusions of asm/system.h
Add #includes needed to permit the removal of asm/system.h
Move all declarations of free_initmem() to linux/mm.h
Disintegrate asm/system.h for OpenRISC
Split arch_align_stack() out from asm-generic/system.h
Split the switch_to() wrapper out of asm-generic/system.h
Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h
Create asm-generic/barrier.h
Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h
Disintegrate asm/system.h for Xtensa
Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]
Disintegrate asm/system.h for Tile
Disintegrate asm/system.h for Sparc
Disintegrate asm/system.h for SH
Disintegrate asm/system.h for Score
Disintegrate asm/system.h for S390
Disintegrate asm/system.h for PowerPC
Disintegrate asm/system.h for PA-RISC
Disintegrate asm/system.h for MN10300
...
Remove all #inclusions of asm/system.h preparatory to splitting and killing
it. Performed with the following command:
perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: David Howells <dhowells@redhat.com>
When using multicast over a local bridge feeding a number of LXC guests
using veth, the LXC guests are unable to get a response from other guests
when pinging 224.0.0.1. Multicast packets did not appear to be getting
delivered to the network namespaces of the guest hosts, and further
inspection showed that the incoming route was pointing to the loopback
device of the host, not the guest. This lead to the wrong network namespace
being picked up by sockets (like ICMP). Fix this by using the correct
network namespace when creating the inbound route entry.
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The following patch aimed to resolve an issue where secondary, tertiary,
etc. addresses added to bond interfaces could overwrite the
bond->master_ip and vlan_ip values.
commit 917fbdb32f
Author: Henrik Saavedra Persson <henrik.e.persson@ericsson.com>
Date: Wed Nov 23 23:37:15 2011 +0000
bonding: only use primary address for ARP
That patch was good because it prevented bonds using ARP monitoring from
sending frames with an invalid source IP address. Unfortunately, it
didn't always work as expected.
When using an ioctl (like ifconfig does) to set the IP address and
netmask, 2 separate ioctls are actually called to set the IP and netmask
if the mask chosen doesn't match the standard mask for that class of
address. The first ioctl did not have a mask that matched the one in
the primary address and would still cause the device address to be
overwritten. The second ioctl that was called to set the mask would
then detect as secondary and ignored, but the damage was already done.
This was not an issue when using an application that used netlink
sockets as the setting of IP and netmask came down at once. The
inconsistent behavior between those two interfaces was something that
needed to be resolved.
While I was thinking about how I wanted to resolve this, Ralf Zeidler
came with a patch that resolved this on a RHEL kernel by keeping a full
shadow of the entries in dev->ifa_list for the bonding device and vlan
devices in the bonding driver. I didn't like the duplication of the
list as I want to see the 'bonding' struct and code shrink rather than
grow, but liked the general idea.
As the Subject indicates this patch drops the master_ip and vlan_ip
elements from the 'bonding' and 'vlan_entry' structs, respectively.
This can be done because a device's address-list is now traversed to
determine the optimal source IP address for ARP requests and for checks
to see if the bonding device has a particular IP address. This code
could have all be contained inside the bonding driver, but it made more
sense to me to EXPORT and call inet_confirm_addr since it did exactly
what was needed.
I tested this and a backported patch and everything works as expected.
Ralf also helped with verification of the backported patch.
Thanks to Ralf for all his help on this.
v2: Whitespace and organizational changes based on suggestions from Jay
Vosburgh and Dave Miller.
v3: Fixup incorrect usage of rcu_read_unlock based on Dave Miller's
suggestion.
Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
CC: Ralf Zeidler <ralf.zeidler@nsn.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It used to be an int, and it got changed to a bool parameter at least
7 years ago. It happens that NF_ACCEPT and NF_DROP are 0 and 1, so
this works, but it's unclear, and the check that it's in range is not
required.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking merge from David Miller:
"1) Move ixgbe driver over to purely page based buffering on receive.
From Alexander Duyck.
2) Add receive packet steering support to e1000e, from Bruce Allan.
3) Convert TCP MD5 support over to RCU, from Eric Dumazet.
4) Reduce cpu usage in handling out-of-order TCP packets on modern
systems, also from Eric Dumazet.
5) Support the IP{,V6}_UNICAST_IF socket options, making the wine
folks happy, from Erich Hoover.
6) Support VLAN trunking from guests in hyperv driver, from Haiyang
Zhang.
7) Support byte-queue-limtis in r8169, from Igor Maravic.
8) Outline code intended for IP_RECVTOS in IP_PKTOPTIONS existed but
was never properly implemented, Jiri Benc fixed that.
9) 64-bit statistics support in r8169 and 8139too, from Junchang Wang.
10) Support kernel side dump filtering by ctmark in netfilter
ctnetlink, from Pablo Neira Ayuso.
11) Support byte-queue-limits in gianfar driver, from Paul Gortmaker.
12) Add new peek socket options to assist with socket migration, from
Pavel Emelyanov.
13) Add sch_plug packet scheduler whose queue is controlled by
userland daemons using explicit freeze and release commands. From
Shriram Rajagopalan.
14) Fix FCOE checksum offload handling on transmit, from Yi Zou."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1846 commits)
Fix pppol2tp getsockname()
Remove printk from rds_sendmsg
ipv6: fix incorrent ipv6 ipsec packet fragment
cpsw: Hook up default ndo_change_mtu.
net: qmi_wwan: fix build error due to cdc-wdm dependecy
netdev: driver: ethernet: Add TI CPSW driver
netdev: driver: ethernet: add cpsw address lookup engine support
phy: add am79c874 PHY support
mlx4_core: fix race on comm channel
bonding: send igmp report for its master
fs_enet: Add MPC5125 FEC support and PHY interface selection
net: bpf_jit: fix BPF_S_LDX_B_MSH compilation
net: update the usage of CHECKSUM_UNNECESSARY
fcoe: use CHECKSUM_UNNECESSARY instead of CHECKSUM_PARTIAL on tx
net: do not do gso for CHECKSUM_UNNECESSARY in netif_needs_gso
ixgbe: Fix issues with SR-IOV loopback when flow control is disabled
net/hyperv: Fix the code handling tx busy
ixgbe: fix namespace issues when FCoE/DCB is not enabled
rtlwifi: Remove unused ETH_ADDR_LEN defines
igbvf: Use ETH_ALEN
...
Fix up fairly trivial conflicts in drivers/isdn/gigaset/interface.c and
drivers/net/usb/{Kconfig,qmi_wwan.c} as per David.
Pull cgroup changes from Tejun Heo:
"Out of the 8 commits, one fixes a long-standing locking issue around
tasklist walking and others are cleanups."
* 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: Walk task list under tasklist_lock in cgroup_enable_task_cg_list
cgroup: Remove wrong comment on cgroup_enable_task_cg_list()
cgroup: remove cgroup_subsys argument from callbacks
cgroup: remove extra calls to find_existing_css_set
cgroup: replace tasklist_lock with rcu_read_lock
cgroup: simplify double-check locking in cgroup_attach_proc
cgroup: move struct cgroup_pidlist out from the header file
cgroup: remove cgroup_attach_task_current_cg()
Pull perf events changes for v3.4 from Ingo Molnar:
- New "hardware based branch profiling" feature both on the kernel and
the tooling side, on CPUs that support it. (modern x86 Intel CPUs
with the 'LBR' hardware feature currently.)
This new feature is basically a sophisticated 'magnifying glass' for
branch execution - something that is pretty difficult to extract from
regular, function histogram centric profiles.
The simplest mode is activated via 'perf record -b', and the result
looks like this in perf report:
$ perf record -b any_call,u -e cycles:u branchy
$ perf report -b --sort=symbol
52.34% [.] main [.] f1
24.04% [.] f1 [.] f3
23.60% [.] f1 [.] f2
0.01% [k] _IO_new_file_xsputn [k] _IO_file_overflow
0.01% [k] _IO_vfprintf_internal [k] _IO_new_file_xsputn
0.01% [k] _IO_vfprintf_internal [k] strchrnul
0.01% [k] __printf [k] _IO_vfprintf_internal
0.01% [k] main [k] __printf
This output shows from/to branch columns and shows the highest
percentage (from,to) jump combinations - i.e. the most likely taken
branches in the system. "branches" can also include function calls
and any other synchronous and asynchronous transitions of the
instruction pointer that are not 'next instruction' - such as system
calls, traps, interrupts, etc.
This feature comes with (hopefully intuitive) flat ascii and TUI
support in perf report.
- Various 'perf annotate' visual improvements for us assembly junkies.
It will now recognize function calls in the TUI and by hitting enter
you can follow the call (recursively) and back, amongst other
improvements.
- Multiple threads/processes recording support in perf record, perf
stat, perf top - which is activated via a comma-list of PIDs:
perf top -p 21483,21485
perf stat -p 21483,21485 -ddd
perf record -p 21483,21485
- Support for per UID views, via the --uid paramter to perf top, perf
report, etc. For example 'perf top --uid mingo' will only show the
tasks that I am running, excluding other users, root, etc.
- Jump label restructurings and improvements - this includes the
factoring out of the (hopefully much clearer) include/linux/static_key.h
generic facility:
struct static_key key = STATIC_KEY_INIT_FALSE;
...
if (static_key_false(&key))
do unlikely code
else
do likely code
...
static_key_slow_inc();
...
static_key_slow_inc();
...
The static_key_false() branch will be generated into the code with as
little impact to the likely code path as possible. the
static_key_slow_*() APIs flip the branch via live kernel code patching.
This facility can now be used more widely within the kernel to
micro-optimize hot branches whose likelihood matches the static-key
usage and fast/slow cost patterns.
- SW function tracer improvements: perf support and filtering support.
- Various hardenings of the perf.data ABI, to make older perf.data's
smoother on newer tool versions, to make new features integrate more
smoothly, to support cross-endian recording/analyzing workflows
better, etc.
- Restructuring of the kprobes code, the splitting out of 'optprobes',
and a corner case bugfix.
- Allow the tracing of kernel console output (printk).
- Improvements/fixes to user-space RDPMC support, allowing user-space
self-profiling code to extract PMU counts without performing any
system calls, while playing nice with the kernel side.
- 'perf bench' improvements
- ... and lots of internal restructurings, cleanups and fixes that made
these features possible. And, as usual this list is incomplete as
there were also lots of other improvements
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits)
perf report: Fix annotate double quit issue in branch view mode
perf report: Remove duplicate annotate choice in branch view mode
perf/x86: Prettify pmu config literals
perf report: Enable TUI in branch view mode
perf report: Auto-detect branch stack sampling mode
perf record: Add HEADER_BRANCH_STACK tag
perf record: Provide default branch stack sampling mode option
perf tools: Make perf able to read files from older ABIs
perf tools: Fix ABI compatibility bug in print_event_desc()
perf tools: Enable reading of perf.data files from different ABI rev
perf: Add ABI reference sizes
perf report: Add support for taken branch sampling
perf record: Add support for sampling taken branch
perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK
x86/kprobes: Split out optprobe related code to kprobes-opt.c
x86/kprobes: Fix a bug which can modify kernel code permanently
x86/kprobes: Fix instruction recovery on optimized path
perf: Add callback to flush branch_stack on context switch
perf: Disable PERF_SAMPLE_BRANCH_* when not supported
perf/x86: Add LBR software filter support for Intel CPUs
...
Pull RCU changes for v3.4 from Ingo Molnar. The major features of this
series are:
- making RCU more aggressive about entering dyntick-idle mode in order
to improve energy efficiency
- converting a few more call_rcu()s to kfree_rcu()s
- applying a number of rcutree fixes and cleanups to rcutiny
- removing CONFIG_SMP #ifdefs from treercu
- allowing RCU CPU stall times to be set via sysfs
- adding CPU-stall capability to rcutorture
- adding more RCU-abuse diagnostics
- updating documentation
- fixing yet more issues located by the still-ongoing top-to-bottom
inspection of RCU, this time with a special focus on the CPU-hotplug
code path.
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (48 commits)
rcu: Stop spurious warnings from synchronize_sched_expedited
rcu: Hold off RCU_FAST_NO_HZ after timer posted
rcu: Eliminate softirq-mediated RCU_FAST_NO_HZ idle-entry loop
rcu: Add RCU_NONIDLE() for idle-loop RCU read-side critical sections
rcu: Allow nesting of rcu_idle_enter() and rcu_idle_exit()
rcu: Remove redundant check for rcu_head misalignment
PTR_ERR should be called before its argument is cleared.
rcu: Convert WARN_ON_ONCE() in rcu_lock_acquire() to lockdep
rcu: Trace only after NULL-pointer check
rcu: Call out dangers of expedited RCU primitives
rcu: Rework detection of use of RCU by offline CPUs
lockdep: Add CPU-idle/offline warning to lockdep-RCU splat
rcu: No interrupt disabling for rcu_prepare_for_idle()
rcu: Move synchronize_sched_expedited() to rcutree.c
rcu: Check for illegal use of RCU from offlined CPUs
rcu: Update stall-warning documentation
rcu: Add CPU-stall capability to rcutorture
rcu: Make documentation give more realistic rcutorture duration
rcutorture: Permit holding off CPU-hotplug operations during boot
rcu: Print scheduling-clock information on RCU CPU stall-warning messages
...
With increasing receive window sizes, but speed of light not improved
that much, out of order queue can contain a huge number of skbs, waiting
to be moved to receive_queue when missing packets can fill the holes.
Some devices happen to use fat skbs (truesize of 4096 + sizeof(struct
sk_buff)) to store regular (MTU <= 1500) frames. This makes highly
probable sk_rmem_alloc hits sk_rcvbuf limit, which can be 4Mbytes in
many cases.
When limit is hit, tcp stack calls tcp_collapse_ofo_queue(), a true
latency killer and cpu cache blower.
Doing the coalescing attempt each time we add a frame in ofo queue
permits to keep memory use tight and in many cases avoid the
tcp_collapse() thing later.
Tested on various wireless setups (b43, ath9k, ...) known to use big skb
truesize, this patch removed the "packets collapsed in receive queue due
to low socket buffer" I had before.
This also reduced average memory used by tcp sockets.
With help from Neal Cardwell.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: H.K. Jerry Chu <hkchu@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Split tcp_data_queue() in two parts for better readability.
tcp_data_queue_ofo() is responsible for queueing incoming skb into out
of order queue.
Change code layout so that the skb_set_owner_r() is performed only if
skb is not dropped.
This is a preliminary patch before "reduce out_of_order memory use"
following patch.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: H.K. Jerry Chu <hkchu@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I found recently that the arp_process function which handles all of our received
arp frames, is using IPV4_DEVCONF_ALL macro to check the state of the arp_process
flag. This seems wrong, as it implies that either none or all of the network
interfaces accept gratuitous arps. This patch corrects that, allowing
per-interface arp_accept configuration to deviate from the all setting. Note
this also brings us into line with the way the arp_filter setting is handled
during arp_process execution.
Tested this myself on my home network, and confirmed it works as expected.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add #define pr_fmt(fmt) as appropriate.
Add "IPv4: ", "TCP: ", and "IPsec: " to appropriate files.
Standardize on "UDPLite: " for appropriate uses.
Some prefixes were previously "UDPLITE: " and "UDP-Lite: ".
Add KBUILD_MODNAME ": " to icmp and gre.
Remove embedded prefixes as appropriate.
Add missing "\n" to pr_info in gre.c.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use a more current kernel messaging style.
Convert a printk block to print_hex_dump.
Coalesce formats, align arguments.
Use %s, __func__ instead of embedding function names.
Some messages that were prefixed with <foo>_close are
now prefixed with <foo>_fini. Some ah4 and esp messages
are now not prefixed with "ip ".
The intent of this patch is to later add something like
#define pr_fmt(fmt) "IPv4: " fmt.
to standardize the output messages.
Text size is trivially reduced. (x86-32 allyesconfig)
$ size net/ipv4/built-in.o*
text data bss dec hex filename
887888 31558 249696 1169142 11d6f6 net/ipv4/built-in.o.new
887934 31558 249800 1169292 11d78c net/ipv4/built-in.o.old
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit ea4fc0d619 (ipv4: Don't use rt->rt_{src,dst} in ip_queue_xmit())
added a serious regression on synflood handling.
Simon Kirby discovered a successful connection was delayed by 20 seconds
before being responsive.
In my tests, I discovered that xmit frames were lost, and needed ~4
retransmits and a socket dst rebuild before being really sent.
In case of syncookie initiated connection, we use a different path to
initialize the socket dst, and inet->cork.fl.u.ip4 is left cleared.
As ip_queue_xmit() now depends on inet flow being setup, fix this by
copying the temp flowi4 we use in cookie_v4_check().
Reported-by: Simon Kirby <sim@netnation.com>
Bisected-by: Simon Kirby <sim@netnation.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As we invalidate the inetpeer tree along with the routing cache now,
we don't need a genid to reset the redirect handling when the routing
cache is flushed.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We initialize the routing metrics with the values cached on the
inetpeer in rt_init_metrics(). So if we have the metrics cached on the
inetpeer, we ignore the user configured fib_metrics.
To fix this issue, we replace the old tree with a fresh initialized
inet_peer_base. The old tree is removed later with a delayed work queue.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit a8afca0329 (tcp: md5: protects md5sig_info with RCU) added a
lockdep splat in tcp_md5_do_lookup() in case a timer fires a tcp
retransmit.
At this point, socket lock is owned by the sofirq handler, not the user,
so we should adjust a bit the lockdep condition, as we dont hold
rcu_read_lock().
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the infrastructure to add fine timeout tuning
over nfnetlink. Now you can use the NFNL_SUBSYS_CTNETLINK_TIMEOUT
subsystem to create/delete/dump timeout objects that contain some
specific timeout policy for one flow.
The follow up patches will allow you attach timeout policy object
to conntrack via the CT target and the conntrack extension
infrastructure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch defines a new interface for l4 protocol trackers:
unsigned int *(*get_timeouts)(struct net *net);
that is used to return the array of unsigned int that contains
the timeouts that will be applied for this flow. This is passed
to the l4proto->new(...) and l4proto->packet(...) functions to
specify the timeout policy.
This interface allows per-net global timeout configuration
(although only DCCP supports this by now) and it will allow
custom custom timeout configuration by means of follow-up
patches.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
ipt_LOG and ip6_LOG have a lot of common code, merge them
to reduce duplicate code.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch allows you to set expectfn which is specifically used
by the NAT side of most of the existing conntrack helpers.
I have added a symbol map that uses a string as key to look up for
the function that is attached to the expectation object. This is
the best solution I came out with to solve this issue.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit fixes tcp_shift_skb_data() so that it does not shift
SACKed data below snd_una.
This fixes an issue whose symptoms exactly match reports showing
tp->sacked_out going negative since 3.3.0-rc4 (see "WARNING: at
net/ipv4/tcp_input.c:3418" thread on netdev).
Since 2008 (832d11c5cd)
tcp_shift_skb_data() had been shifting SACKed ranges that were below
snd_una. It checked that the *end* of the skb it was about to shift
from was above snd_una, but did not check that the end of the actual
shifted range was above snd_una; this commit adds that check.
Shifting SACKed ranges below snd_una is problematic because for such
ranges tcp_sacktag_one() short-circuits: it does not declare anything
as SACKed and does not increase sacked_out.
Before the fixes in commits cc9a672ee5
and daef52bab1, shifting SACKed ranges
below snd_una happened to work because tcp_shifted_skb() was always
(incorrectly) passing in to tcp_sacktag_one() an skb whose end_seq
tcp_shift_skb_data() had already guaranteed was beyond snd_una. Hence
tcp_sacktag_one() never short-circuited and always increased
tp->sacked_out in this case.
After those two fixes, my testing has verified that shifting SACKed
ranges below snd_una could cause tp->sacked_out to go negative with
the following sequence of events:
(1) tcp_shift_skb_data() sees an skb whose end_seq is beyond snd_una,
then shifts a prefix of that skb that is below snd_una
(2) tcp_shifted_skb() increments the packet count of the
already-SACKed prev sk_buff
(3) tcp_sacktag_one() sees the end of the new SACKed range is below
snd_una, so it short-circuits and doesn't increase tp->sacked_out
(5) tcp_clean_rtx_queue() sees the SACKed skb has been ACKed,
decrements tp->sacked_out by this "inflated" pcount that was
missing a matching increase in tp->sacked_out, and hence
tp->sacked_out underflows to a u32 like 0xFFFFFFFF, which casted
to s32 is negative.
(6) this leads to the warnings seen in the recent "WARNING: at
net/ipv4/tcp_input.c:3418" thread on the netdev list; e.g.:
tcp_input.c:3418 WARN_ON((int)tp->sacked_out < 0);
More generally, I think this bug can be tickled in some cases where
two or more ACKs from the receiver are lost and then a DSACK arrives
that is immediately above an existing SACKed skb in the write queue.
This fix changes tcp_shift_skb_data() to abort this sequence at step
(1) in the scenario above by noticing that the bytes are below snd_una
and not shifting them.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/vmxnet3/vmxnet3_drv.c
Small vmxnet3 conflict with header size bug fix in 'net'.
Signed-off-by: David S. Miller <davem@davemloft.net>
In tcp_mark_head_lost() we should not attempt to fragment a SACKed skb
to mark the first portion as lost. This is for two primary reasons:
(1) tcp_shifted_skb() coalesces adjacent regions of SACKed skbs. When
doing this, it preserves the sum of their packet counts in order to
reflect the real-world dynamics on the wire. But given that skbs can
have remainders that do not align to MSS boundaries, this packet count
preservation means that for SACKed skbs there is not necessarily a
direct linear relationship between tcp_skb_pcount(skb) and
skb->len. Thus tcp_mark_head_lost()'s previous attempts to fragment
off and mark as lost a prefix of length (packets - oldcnt)*mss from
SACKed skbs were leading to occasional failures of the WARN_ON(len >
skb->len) in tcp_fragment() (which used to be a BUG_ON(); see the
recent "crash in tcp_fragment" thread on netdev).
(2) there is no real point in fragmenting off part of a SACKed skb and
calling tcp_skb_mark_lost() on it, since tcp_skb_mark_lost() is a NOP
for SACKed skbs.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/broadcom/tg3.c
Conflicts in the statistics regression bug fix from 'net',
but happily Matt Carlson originally posted the fix against
'net-next' so I used that to resolve this.
Signed-off-by: David S. Miller <davem@davemloft.net>
When tcp_shifted_skb() shifts bytes from the skb that is currently
pointed to by 'highest_sack' then the increment of
TCP_SKB_CB(skb)->seq implicitly advances tcp_highest_sack_seq(). This
implicit advancement, combined with the recent fix to pass the correct
SACKed range into tcp_sacktag_one(), caused tcp_sacktag_one() to think
that the newly SACKed range was before the tcp_highest_sack_seq(),
leading to a call to tcp_update_reordering() with a degree of
reordering matching the size of the newly SACKed range (typically just
1 packet, which is a NOP, but potentially larger).
This commit fixes this by simply calling tcp_sacktag_one() before the
TCP_SKB_CB(skb)->seq advancement that can advance our notion of the
highest SACKed sequence.
Correspondingly, we can simplify the code a little now that
tcp_shifted_skb() should update the lost_cnt_hint in all cases where
skb == tp->lost_skb_hint.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The major features of this series are:
- making RCU more aggressive about entering dyntick-idle mode in order to
improve energy efficiency
- converting a few more call_rcu()s to kfree_rcu()s
- applying a number of rcutree fixes and cleanups to rcutiny
- removing CONFIG_SMP #ifdefs from treercu
- allowing RCU CPU stall times to be set via sysfs
- adding CPU-stall capability to rcutorture
- adding more RCU-abuse diagnostics
- updating documentation
- fixing yet more issues located by the still-ongoing top-to-bottom
inspection of RCU, this time with a special focus on the
CPU-hotplug code path.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Conflicts:
drivers/net/ethernet/sfc/rx.c
Overlapping changes in drivers/net/ethernet/sfc/rx.c, one to change
the rx_buf->is_page boolean into a set of u16 flags, and another to
adjust how ->ip_summed is initialized.
Signed-off-by: David S. Miller <davem@davemloft.net>
1) ICMP sockets leave err uninitialized but we try to return it for the
unsupported MSG_OOB case, reported by Dave Jones.
2) Add new Zaurus device ID entries, from Dave Jones.
3) Pointer calculation in hso driver memset is wrong, from Dan
Carpenter.
4) ks8851_probe() checks unsigned value as negative, fix also from Dan
Carpenter.
5) Fix crashes in atl1c driver due to TX queue handling, from Eric
Dumazet. I anticipate some TX side locking fixes coming in the near
future for this driver as well.
6) The inline directive fix in Bluetooth which was breaking the build
only with very new versions of GCC, from Johan Hedberg.
7) Fix crashes in the ATP CLIP code due to ARP cleanups this merge
window, reported by Meelis Roos and fixed by Eric Dumazet.
8) JME driver doesn't flush RX FIFO correctly, from Guo-Fu Tseng.
9) Some ip6_route_output() callers test the return value for NULL, but
this never happens as the convention is to return a dst entry with
dst->error set. Fixes from RonQing Li.
10) Logitech Harmony 900 should be handled by zaurus driver not
cdc_ether, update white lists and black lists accordingly. From
Scott Talbert.
11) Receiving from certain kinds of devices there won't be a MAC header,
so there is no MAC header to fixup in the IPSEC code, and if we try
to do it we'll crash. Fix from Eric Dumazet.
12) Port type array indexing off-by-one in mlx4 driver, fix from Yevgeny
Petrilin.
13) Fix regression in link-down handling in davinci_emac which causes
all RX descriptors to be freed up and therefore RX to wedge
completely, from Christian Riesch.
14) It took two attempts, but ctnetlink soft lockups seem to be
cured now, from Pablo Neira Ayuso.
15) Endianness bug fix in ENIC driver, from Santosh Nayak.
16) The long ago conversion of the PPP fragmentation code over to
abstracted SKB list handling wasn't perfect, once we get an
out of sequence SKB we don't flush the rest of them like we
should. From Ben McKeegan.
17) Fix regression of ->ip_summed initialization in sfc driver.
From Ben Hutchings.
18) Bluetooth timeout mistakenly using msecs instead of jiffies,
from Andrzej Kaczmarek.
19) Using _sync variant of work cancellation results in deadlocks,
use the non _sync variants instead. From Andre Guedes.
20) Bluetooth rfcomm code had reference counting problems leading
to crashes, fix from Octavian Purdila.
21) The conversion of netem over to classful qdisc handling added
two bugs to netem_dequeue(), fixes from Eric Dumazet.
22) Missing pci_iounmap() in ATM Solos driver. Fix from Julia Lawall.
23) b44_pci_exit() should not have __exit tag since it's invoked from
non-__exit code. From Nikola Pajkovsky.
24) The conversion of the neighbour hash tables over to RCU added a
race, fixed here by adding the necessary reread of tbl->nht, fix
from Michel Machado.
25) When we added VF (virtual function) attributes for network device
dumps, this potentially bloats up the size of the dump of one
network device such that the dump size is too large for the buffer
allocated by properly written netlink applications.
In particular, if you add 255 VFs to a network device, parts of
GLIBC stop working.
To fix this, we add an attribute that is used to turn on these
extended portions of the network device dump. Sophisticaed
applications like 'ip' that want to see this stuff will be changed
to set the attribute, whereas things like GLIBC that don't care
about VFs simply will not, and therefore won't be busted by the
mere presence of VFs on a network device.
Thanks to the tireless work of Greg Rose on this fix.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (53 commits)
sfc: Fix assignment of ip_summed for pre-allocated skbs
ppp: fix 'ppp_mp_reconstruct bad seq' errors
enic: Fix endianness bug.
gre: fix spelling in comments
netfilter: ctnetlink: fix soft lockup when netlink adds new entries (v2)
Revert "netfilter: ctnetlink: fix soft lockup when netlink adds new entries"
davinci_emac: Do not free all rx dma descriptors during init
mlx4_core: Fixing array indexes when setting port types
phy: IC+101G and PHY_HAS_INTERRUPT flag
netdev/phy/icplus: Correct broken phy_init code
ipsec: be careful of non existing mac headers
Move Logitech Harmony 900 from cdc_ether to zaurus
hso: memsetting wrong data in hso_get_count()
netfilter: ip6_route_output() never returns NULL.
ethernet/broadcom: ip6_route_output() never returns NULL.
ipv6: ip6_route_output() never returns NULL.
jme: Fix FIFO flush issue
atm: clip: remove clip_tbl
ipv4: ping: Fix recvmsg MSG_OOB error handling.
rtnetlink: Fix problem with buffer allocation
...
Davem considers that the argument list of this interface is getting
out of control. This patch tries to address this issue following
his proposal:
struct netlink_dump_control c = { .dump = dump, .done = done, ... };
netlink_dump_start(..., &c);
Suggested by David S. Miller.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The original spelling and bad word choice makes these comments hard to read.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
So here's a boot tested patch on top of Jason's series that does
all the cleanups I talked about and turns jump labels into a
more intuitive to use facility. It should also address the
various misconceptions and confusions that surround jump labels.
Typical usage scenarios:
#include <linux/static_key.h>
struct static_key key = STATIC_KEY_INIT_TRUE;
if (static_key_false(&key))
do unlikely code
else
do likely code
Or:
if (static_key_true(&key))
do likely code
else
do unlikely code
The static key is modified via:
static_key_slow_inc(&key);
...
static_key_slow_dec(&key);
The 'slow' prefix makes it abundantly clear that this is an
expensive operation.
I've updated all in-kernel code to use this everywhere. Note
that I (intentionally) have not pushed through the rename
blindly through to the lowest levels: the actual jump-label
patching arch facility should be named like that, so we want to
decouple jump labels from the static-key facility a bit.
On non-jump-label enabled architectures static keys default to
likely()/unlikely() branches.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jason Baron <jbaron@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: a.p.zijlstra@chello.nl
Cc: mathieu.desnoyers@efficios.com
Cc: davem@davemloft.net
Cc: ddaney.cavm@gmail.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Niccolo Belli reported ipsec crashes in case we handle a frame without
mac header (atm in his case)
Before copying mac header, better make sure it is present.
Bugzilla reference: https://bugzilla.kernel.org/show_bug.cgi?id=42809
Reported-by: Niccolò Belli <darkbasic@linuxsystems.it>
Tested-by: Niccolò Belli <darkbasic@linuxsystems.it>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't return an uninitialized variable as the error, return
-EOPNOTSUPP instead.
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This one is only considered for MSG_PEEK flag and the value pointed by
it specifies where to start peeking bytes from. If the offset happens to
point into the middle of the returned skb, the offset within this skb is
put back to this very argument.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The call_rcu() in do_ip_setsockopt() invokes opt_kfree_rcu(), which just
calls kfree(). So convert the call_rcu() to kfree_rcu(), which allows
opt_kfree_rcu() to be eliminated.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: netdev@vger.kernel.org
Because opt_kfree_rcu() just calls kfree(), all call_rcu() uses of it
may be converted to kfree_rcu(). This permits opt_kfree_rcu() to
be eliminated.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: netdev@vger.kernel.org
Assorted fixes, sat in -next for a week or so...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ocfs2: deal with wraparounds of i_nlink in ocfs2_rename()
vfs: fix compat_sys_stat() handling of overflows in st_nlink
quota: Fix deadlock with suspend and quotas
vfs: Provide function to get superblock and wait for it to thaw
vfs: fix panic in __d_lookup() with high dentry hashtable counts
autofs4 - fix lockdep splat in autofs
vfs: fix d_inode_lookup() dentry ref leak
Conflicts:
drivers/net/ethernet/broadcom/bnx2x/bnx2x_stats.c
Small minor conflict in bnx2x, wherein one commit changed how
statistics were stored in software, and another commit
fixed endianness bugs wrt. reading the values provided by
the chip in memory.
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet
Linus Torvalds
David Howells
Benjamin LaHaise
Andy Gospodarek
Rusty Russell
David S. Miller
Neil Horman
Joe Perches
Ingo Molnar
Steffen Klassert
Pablo Neira Ayuso
Richard Weinberger
Neal Cardwell
stephen hemminger
Pavel Emelyanov
Paul E. McKenney