Граф коммитов

49 Коммитов

Автор SHA1 Сообщение Дата
Davide Caratti 44d4775ca5 net/sched: sch_taprio: reset child qdiscs before freeing them
syzkaller shows that packets can still be dequeued while taprio_destroy()
is running. Let sch_taprio use the reset() function to cancel the advance
timer and drop all skbs from the child qdiscs.

Fixes: 5a781ccbd1 ("tc: Add support for configuring the taprio scheduler")
Link: https://syzkaller.appspot.com/bug?id=f362872379bf8f0017fb667c1ab158f2d1e764ae
Reported-by: syzbot+8971da381fb5a31f542d@syzkaller.appspotmail.com
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Link: https://lore.kernel.org/r/63b6d79b0e830ebb0283e020db4df3cdfdfb2b94.1608142843.git.dcaratti@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-17 10:57:57 -08:00
Jakub Kicinski cc69837fca net: don't include ethtool.h from netdevice.h
linux/netdevice.h is included in very many places, touching any
of its dependecies causes large incremental builds.

Drop the linux/ethtool.h include, linux/netdevice.h just needs
a forward declaration of struct ethtool_ops.

Fix all the places which made use of this implicit include.

Acked-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Shannon Nelson <snelson@pensando.io>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Link: https://lore.kernel.org/r/20201120225052.1427503-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-23 17:27:04 -08:00
Vinicius Costa Gomes b5b73b26b3 taprio: Fix allowing too small intervals
It's possible that the user specifies an interval that couldn't allow
any packet to be transmitted. This also avoids the issue of the
hrtimer handler starving the other threads because it's running too
often.

The solution is to reject interval sizes that according to the current
link speed wouldn't allow any packet to be transmitted.

Reported-by: syzbot+8267241609ae8c23b248@syzkaller.appspotmail.com
Fixes: 5a781ccbd1 ("tc: Add support for configuring the taprio scheduler")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-11 17:21:51 -07:00
Vinicius Costa Gomes 09e31cf0c5 taprio: Fix using wrong queues in gate mask
Since commit 9c66d15646 ("taprio: Add support for hardware
offloading") there's a bit of inconsistency when offloading schedules
to the hardware:

In software mode, the gate masks are specified in terms of traffic
classes, so if say "sched-entry S 03 20000", it means that the traffic
classes 0 and 1 are open for 20us; when taprio is offloaded to
hardware, the gate masks are specified in terms of hardware queues.

The idea here is to fix hardware offloading, so schedules in hardware
and software mode have the same behavior. What's needed to do is to
map traffic classes to queues when applying the offload to the driver.

Fixes: 9c66d15646 ("taprio: Add support for hardware offloading")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-26 15:45:11 -07:00
Petr Machata ac5c66f261 Revert "net: sched: Pass root lock to Qdisc_ops.enqueue"
This reverts commit aebe4426cc.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-07-16 16:48:34 -07:00
Petr Machata aebe4426cc net: sched: Pass root lock to Qdisc_ops.enqueue
A following patch introduces qevents, points in qdisc algorithm where
packet can be processed by user-defined filters. Should this processing
lead to a situation where a new packet is to be enqueued on the same port,
holding the root lock would lead to deadlocks. To solve the issue, qevent
handler needs to unlock and relock the root lock when necessary.

To that end, add the root lock argument to the qdisc op enqueue, and
propagate throughout.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-29 17:08:28 -07:00
Gustavo A. R. Silva 11a33de2df taprio: Use struct_size() in kzalloc()
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes. Also, remove unnecessary
variable _size_.

This code was detected with the help of Coccinelle and, audited and
fixed manually.

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-19 20:18:43 -07:00
Vinicius Costa Gomes b09fe70ef5 taprio: Fix sending packets without dequeueing them
There was a bug that was causing packets to be sent to the driver
without first calling dequeue() on the "child" qdisc. And the KASAN
report below shows that sending a packet without calling dequeue()
leads to bad results.

The problem is that when checking the last qdisc "child" we do not set
the returned skb to NULL, which can cause it to be sent to the driver,
and so after the skb is sent, it may be freed, and in some situations a
reference to it may still be in the child qdisc, because it was never
dequeued.

The crash log looks like this:

[   19.937538] ==================================================================
[   19.938300] BUG: KASAN: use-after-free in taprio_dequeue_soft+0x620/0x780
[   19.938968] Read of size 4 at addr ffff8881128628cc by task swapper/1/0
[   19.939612]
[   19.939772] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc3+ #97
[   19.940397] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qe4
[   19.941523] Call Trace:
[   19.941774]  <IRQ>
[   19.941985]  dump_stack+0x97/0xe0
[   19.942323]  print_address_description.constprop.0+0x3b/0x60
[   19.942884]  ? taprio_dequeue_soft+0x620/0x780
[   19.943325]  ? taprio_dequeue_soft+0x620/0x780
[   19.943767]  __kasan_report.cold+0x1a/0x32
[   19.944173]  ? taprio_dequeue_soft+0x620/0x780
[   19.944612]  kasan_report+0xe/0x20
[   19.944954]  taprio_dequeue_soft+0x620/0x780
[   19.945380]  __qdisc_run+0x164/0x18d0
[   19.945749]  net_tx_action+0x2c4/0x730
[   19.946124]  __do_softirq+0x268/0x7bc
[   19.946491]  irq_exit+0x17d/0x1b0
[   19.946824]  smp_apic_timer_interrupt+0xeb/0x380
[   19.947280]  apic_timer_interrupt+0xf/0x20
[   19.947687]  </IRQ>
[   19.947912] RIP: 0010:default_idle+0x2d/0x2d0
[   19.948345] Code: 00 00 41 56 41 55 65 44 8b 2d 3f 8d 7c 7c 41 54 55 53 0f 1f 44 00 00 e8 b1 b2 c5 fd e9 07 00 3
[   19.950166] RSP: 0018:ffff88811a3efda0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
[   19.950909] RAX: 0000000080000000 RBX: ffff88811a3a9600 RCX: ffffffff8385327e
[   19.951608] RDX: 1ffff110234752c0 RSI: 0000000000000000 RDI: ffffffff8385262f
[   19.952309] RBP: ffffed10234752c0 R08: 0000000000000001 R09: ffffed10234752c1
[   19.953009] R10: ffffed10234752c0 R11: ffff88811a3a9607 R12: 0000000000000001
[   19.953709] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000
[   19.954408]  ? default_idle_call+0x2e/0x70
[   19.954816]  ? default_idle+0x1f/0x2d0
[   19.955192]  default_idle_call+0x5e/0x70
[   19.955584]  do_idle+0x3d4/0x500
[   19.955909]  ? arch_cpu_idle_exit+0x40/0x40
[   19.956325]  ? _raw_spin_unlock_irqrestore+0x23/0x30
[   19.956829]  ? trace_hardirqs_on+0x30/0x160
[   19.957242]  cpu_startup_entry+0x19/0x20
[   19.957633]  start_secondary+0x2a6/0x380
[   19.958026]  ? set_cpu_sibling_map+0x18b0/0x18b0
[   19.958486]  secondary_startup_64+0xa4/0xb0
[   19.958921]
[   19.959078] Allocated by task 33:
[   19.959412]  save_stack+0x1b/0x80
[   19.959747]  __kasan_kmalloc.constprop.0+0xc2/0xd0
[   19.960222]  kmem_cache_alloc+0xe4/0x230
[   19.960617]  __alloc_skb+0x91/0x510
[   19.960967]  ndisc_alloc_skb+0x133/0x330
[   19.961358]  ndisc_send_ns+0x134/0x810
[   19.961735]  addrconf_dad_work+0xad5/0xf80
[   19.962144]  process_one_work+0x78e/0x13a0
[   19.962551]  worker_thread+0x8f/0xfa0
[   19.962919]  kthread+0x2ba/0x3b0
[   19.963242]  ret_from_fork+0x3a/0x50
[   19.963596]
[   19.963753] Freed by task 33:
[   19.964055]  save_stack+0x1b/0x80
[   19.964386]  __kasan_slab_free+0x12f/0x180
[   19.964830]  kmem_cache_free+0x80/0x290
[   19.965231]  ip6_mc_input+0x38a/0x4d0
[   19.965617]  ipv6_rcv+0x1a4/0x1d0
[   19.965948]  __netif_receive_skb_one_core+0xf2/0x180
[   19.966437]  netif_receive_skb+0x8c/0x3c0
[   19.966846]  br_handle_frame_finish+0x779/0x1310
[   19.967302]  br_handle_frame+0x42a/0x830
[   19.967694]  __netif_receive_skb_core+0xf0e/0x2a90
[   19.968167]  __netif_receive_skb_one_core+0x96/0x180
[   19.968658]  process_backlog+0x198/0x650
[   19.969047]  net_rx_action+0x2fa/0xaa0
[   19.969420]  __do_softirq+0x268/0x7bc
[   19.969785]
[   19.969940] The buggy address belongs to the object at ffff888112862840
[   19.969940]  which belongs to the cache skbuff_head_cache of size 224
[   19.971202] The buggy address is located 140 bytes inside of
[   19.971202]  224-byte region [ffff888112862840, ffff888112862920)
[   19.972344] The buggy address belongs to the page:
[   19.972820] page:ffffea00044a1800 refcount:1 mapcount:0 mapping:ffff88811a2bd1c0 index:0xffff8881128625c0 compo0
[   19.973930] flags: 0x8000000000010200(slab|head)
[   19.974388] raw: 8000000000010200 ffff88811a2ed650 ffff88811a2ed650 ffff88811a2bd1c0
[   19.975151] raw: ffff8881128625c0 0000000000190013 00000001ffffffff 0000000000000000
[   19.975915] page dumped because: kasan: bad access detected
[   19.976461] page_owner tracks the page as allocated
[   19.976946] page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NO)
[   19.978332]  prep_new_page+0x24b/0x330
[   19.978707]  get_page_from_freelist+0x2057/0x2c90
[   19.979170]  __alloc_pages_nodemask+0x218/0x590
[   19.979619]  new_slab+0x9d/0x300
[   19.979948]  ___slab_alloc.constprop.0+0x2f9/0x6f0
[   19.980421]  __slab_alloc.constprop.0+0x30/0x60
[   19.980870]  kmem_cache_alloc+0x201/0x230
[   19.981269]  __alloc_skb+0x91/0x510
[   19.981620]  alloc_skb_with_frags+0x78/0x4a0
[   19.982043]  sock_alloc_send_pskb+0x5eb/0x750
[   19.982476]  unix_stream_sendmsg+0x399/0x7f0
[   19.982904]  sock_sendmsg+0xe2/0x110
[   19.983262]  ____sys_sendmsg+0x4de/0x6d0
[   19.983660]  ___sys_sendmsg+0xe4/0x160
[   19.984032]  __sys_sendmsg+0xab/0x130
[   19.984396]  do_syscall_64+0xe7/0xae0
[   19.984761] page last free stack trace:
[   19.985142]  __free_pages_ok+0x432/0xbc0
[   19.985533]  qlist_free_all+0x56/0xc0
[   19.985907]  quarantine_reduce+0x149/0x170
[   19.986315]  __kasan_kmalloc.constprop.0+0x9e/0xd0
[   19.986791]  kmem_cache_alloc+0xe4/0x230
[   19.987182]  prepare_creds+0x24/0x440
[   19.987548]  do_faccessat+0x80/0x590
[   19.987906]  do_syscall_64+0xe7/0xae0
[   19.988276]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   19.988775]
[   19.988930] Memory state around the buggy address:
[   19.989402]  ffff888112862780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   19.990111]  ffff888112862800: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
[   19.990822] >ffff888112862880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   19.991529]                                               ^
[   19.992081]  ffff888112862900: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
[   19.992796]  ffff888112862980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc

Fixes: 5a781ccbd1 ("tc: Add support for configuring the taprio scheduler")
Reported-by: Michael Schmidt <michael.schmidt@eti.uni-siegen.de>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Acked-by: Andre Guedes <andre.guedes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-12 11:25:08 -07:00
Jakub Kicinski e13aaa0643 net: taprio: add missing attribute validation for txtime delay
Add missing attribute validation for TCA_TAPRIO_ATTR_TXTIME_DELAY
to the netlink policy.

Fixes: 4cfd5779bd ("taprio: Add support for txtime-assist mode")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-03 13:28:48 -08:00
Vinicius Costa Gomes bfabd41da3 taprio: Fix dropping packets when using taprio + ETF offloading
When using taprio offloading together with ETF offloading, configured
like this, for example:

$ tc qdisc replace dev $IFACE parent root handle 100 taprio \
  	num_tc 4 \
        map 2 2 1 0 3 2 2 2 2 2 2 2 2 2 2 2 \
	queues 1@0 1@1 1@2 1@3 \
	base-time $BASE_TIME \
	sched-entry S 01 1000000 \
	sched-entry S 0e 1000000 \
	flags 0x2

$ tc qdisc replace dev $IFACE parent 100:1 etf \
     	offload delta 300000 clockid CLOCK_TAI

During enqueue, it works out that the verification added for the
"txtime" assisted mode is run when using taprio + ETF offloading, the
only thing missing is initializing the 'next_txtime' of all the cycle
entries. (if we don't set 'next_txtime' all packets from SO_TXTIME
sockets are dropped)

Fixes: 4cfd5779bd ("taprio: Add support for txtime-assist mode")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-07 11:30:03 +01:00
Vinicius Costa Gomes 7c16680a08 taprio: Use taprio_reset_tc() to reset Traffic Classes configuration
When destroying the current taprio instance, which can happen when the
creation of one fails, we should reset the traffic class configuration
back to the default state.

netdev_reset_tc() is a better way because in addition to setting the
number of traffic classes to zero, it also resets the priority to
traffic classes mapping to the default value.

Fixes: 5a781ccbd1 ("tc: Add support for configuring the taprio scheduler")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-07 11:30:03 +01:00
Vinicius Costa Gomes 49c684d79c taprio: Add missing policy validation for flags
netlink policy validation for the 'flags' argument was missing.

Fixes: 4cfd5779bd ("taprio: Add support for txtime-assist mode")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-07 11:30:03 +01:00
Vinicius Costa Gomes a9d6227436 taprio: Fix still allowing changing the flags during runtime
Because 'q->flags' starts as zero, and zero is a valid value, we
aren't able to detect the transition from zero to something else
during "runtime".

The solution is to initialize 'q->flags' with an invalid value, so we
can detect if 'q->flags' was set by the user or not.

To better solidify the behavior, 'flags' handling is moved to a
separate function. The behavior is:
 - 'flags' if unspecified by the user, is assumed to be zero;
 - 'flags' cannot change during "runtime" (i.e. a change() request
 cannot modify it);

With this new function we can remove taprio_flags, which should reduce
the risk of future accidents.

Allowing flags to be changed was causing the following RCU stall:

[ 1730.558249] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
[ 1730.558258] rcu: 	  6-...0: (190 ticks this GP) idle=922/0/0x1 softirq=25580/25582 fqs=16250
[ 1730.558264] 		  (detected by 2, t=65002 jiffies, g=33017, q=81)
[ 1730.558269] Sending NMI from CPU 2 to CPUs 6:
[ 1730.559277] NMI backtrace for cpu 6
[ 1730.559277] CPU: 6 PID: 0 Comm: swapper/6 Tainted: G            E     5.5.0-rc6+ #35
[ 1730.559278] Hardware name: Gigabyte Technology Co., Ltd. Z390 AORUS ULTRA/Z390 AORUS ULTRA-CF, BIOS F7 03/14/2019
[ 1730.559278] RIP: 0010:__hrtimer_run_queues+0xe2/0x440
[ 1730.559278] Code: 48 8b 43 28 4c 89 ff 48 8b 75 c0 48 89 45 c8 e8 f4 bb 7c 00 0f 1f 44 00 00 65 8b 05 40 31 f0 68 89 c0 48 0f a3 05 3e 5c 25 01 <0f> 82 fc 01 00 00 48 8b 45 c8 48 89 df ff d0 89 45 c8 0f 1f 44 00
[ 1730.559279] RSP: 0018:ffff9970802d8f10 EFLAGS: 00000083
[ 1730.559279] RAX: 0000000000000006 RBX: ffff8b31645bff38 RCX: 0000000000000000
[ 1730.559280] RDX: 0000000000000000 RSI: ffffffff9710f2ec RDI: ffffffff978daf0e
[ 1730.559280] RBP: ffff9970802d8f68 R08: 0000000000000000 R09: 0000000000000000
[ 1730.559280] R10: 0000018336d7944e R11: 0000000000000001 R12: ffff8b316e39f9c0
[ 1730.559281] R13: ffff8b316e39f940 R14: ffff8b316e39f998 R15: ffff8b316e39f7c0
[ 1730.559281] FS:  0000000000000000(0000) GS:ffff8b316e380000(0000) knlGS:0000000000000000
[ 1730.559281] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1730.559281] CR2: 00007f1105303760 CR3: 0000000227210005 CR4: 00000000003606e0
[ 1730.559282] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1730.559282] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1730.559282] Call Trace:
[ 1730.559282]  <IRQ>
[ 1730.559283]  ? taprio_dequeue_soft+0x2d0/0x2d0 [sch_taprio]
[ 1730.559283]  hrtimer_interrupt+0x104/0x220
[ 1730.559283]  ? irqtime_account_irq+0x34/0xa0
[ 1730.559283]  smp_apic_timer_interrupt+0x6d/0x230
[ 1730.559284]  apic_timer_interrupt+0xf/0x20
[ 1730.559284]  </IRQ>
[ 1730.559284] RIP: 0010:cpu_idle_poll+0x35/0x1a0
[ 1730.559285] Code: 88 82 ff 65 44 8b 25 12 7d 73 68 0f 1f 44 00 00 e8 90 c3 89 ff fb 65 48 8b 1c 25 c0 7e 01 00 48 8b 03 a8 08 74 0b eb 1c f3 90 <48> 8b 03 a8 08 75 13 8b 05 be a8 a8 00 85 c0 75 ed e8 75 48 84 ff
[ 1730.559285] RSP: 0018:ffff997080137ea8 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
[ 1730.559285] RAX: 0000000000000001 RBX: ffff8b316bc3c580 RCX: 0000000000000000
[ 1730.559286] RDX: 0000000000000001 RSI: 000000002819aad9 RDI: ffffffff978da730
[ 1730.559286] RBP: ffff997080137ec0 R08: 0000018324a6d387 R09: 0000000000000000
[ 1730.559286] R10: 0000000000000400 R11: 0000000000000001 R12: 0000000000000006
[ 1730.559286] R13: ffff8b316bc3c580 R14: 0000000000000000 R15: 0000000000000000
[ 1730.559287]  ? cpu_idle_poll+0x20/0x1a0
[ 1730.559287]  ? cpu_idle_poll+0x20/0x1a0
[ 1730.559287]  do_idle+0x4d/0x1f0
[ 1730.559287]  ? complete+0x44/0x50
[ 1730.559288]  cpu_startup_entry+0x1b/0x20
[ 1730.559288]  start_secondary+0x142/0x180
[ 1730.559288]  secondary_startup_64+0xb6/0xc0
[ 1776.686313] nvme nvme0: I/O 96 QID 1 timeout, completion polled

Fixes: 4cfd5779bd ("taprio: Add support for txtime-assist mode")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-07 11:30:03 +01:00
Vinicius Costa Gomes 5652e63df3 taprio: Fix enabling offload with wrong number of traffic classes
If the driver implementing taprio offloading depends on the value of
the network device number of traffic classes (dev->num_tc) for
whatever reason, it was going to receive the value zero. The value was
only set after the offloading function is called.

So, moving setting the number of traffic classes to before the
offloading function is called fixes this issue. This is safe because
this only happens when taprio is instantiated (we don't allow this
configuration to be changed without first removing taprio).

Fixes: 9c66d15646 ("taprio: Add support for hardware offloading")
Reported-by: Po Liu <po.liu@nxp.com>
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Acked-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-07 11:30:03 +01:00
Ivan Khoronzhuk b5a0faa357 taprio: don't reject same mqprio settings
The taprio qdisc allows to set mqprio setting but only once. In case
if mqprio settings are provided next time the error is returned as
it's not allowed to change traffic class mapping in-flignt and that
is normal. But if configuration is absolutely the same - no need to
return error. It allows to provide same command couple times,
changing only base time for instance, or changing only scheds maps,
but leaving mqprio setting w/o modification. It more corresponds the
message: "Changing the traffic mapping of a running schedule is not
supported", so reject mqprio if it's really changed.

Also corrected TC_BITMASK + 1 for consistency, as proposed.

Fixes: a3d43c0d56 ("taprio: Add support adding an admin schedule")
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-19 15:23:15 -08:00
Ivan Khoronzhuk 0763b3e81a taprio: fix panic while hw offload sched list swap
Don't swap oper and admin schedules too early, it's not correct and
causes crash.

Steps to reproduce:

1)
tc qdisc replace dev eth0 parent root handle 100 taprio \
    num_tc 3 \
    map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \
    queues 1@0 1@1 1@2 \
    base-time $SOME_BASE_TIME \
    sched-entry S 01 80000 \
    sched-entry S 02 15000 \
    sched-entry S 04 40000 \
    flags 2

2)
tc qdisc replace dev eth0 parent root handle 100 taprio \
    base-time $SOME_BASE_TIME \
    sched-entry S 01 90000 \
    sched-entry S 02 20000 \
    sched-entry S 04 40000 \
    flags 2

3)
tc qdisc replace dev eth0 parent root handle 100 taprio \
    base-time $SOME_BASE_TIME \
    sched-entry S 01 150000 \
    sched-entry S 02 200000 \
    sched-entry S 04 40000 \
    flags 2

Do 2 3 2 .. steps  more times if not happens and observe:

[  305.832319] Unable to handle kernel write to read-only memory at
virtual address ffff0000087ce7f0
[  305.910887] CPU: 0 PID: 0 Comm: swapper/0 Not tainted
[  305.919306] Hardware name: Texas Instruments AM654 Base Board (DT)

[...]

[  306.017119] x1 : ffff800848031d88 x0 : ffff800848031d80
[  306.022422] Call trace:
[  306.024866]  taprio_free_sched_cb+0x4c/0x98
[  306.029040]  rcu_process_callbacks+0x25c/0x410
[  306.033476]  __do_softirq+0x10c/0x208
[  306.037132]  irq_exit+0xb8/0xc8
[  306.040267]  __handle_domain_irq+0x64/0xb8
[  306.044352]  gic_handle_irq+0x7c/0x178
[  306.048092]  el1_irq+0xb0/0x128
[  306.051227]  arch_cpu_idle+0x10/0x18
[  306.054795]  do_idle+0x120/0x138
[  306.058015]  cpu_startup_entry+0x20/0x28
[  306.061931]  rest_init+0xcc/0xd8
[  306.065154]  start_kernel+0x3bc/0x3e4
[  306.068810] Code: f2fbd5b7 f2fbd5b6 d503201f f9400422 (f9000662)
[  306.074900] ---[ end trace 96c8e2284a9d9d6e ]---
[  306.079507] Kernel panic - not syncing: Fatal exception in interrupt
[  306.085847] SMP: stopping secondary CPUs
[  306.089765] Kernel Offset: disabled

Try to explain one of the possible crash cases:

The "real" admin list is assigned when admin_sched is set to
new_admin, it happens after "swap", that assigns to oper_sched NULL.
Thus if call qdisc show it can crash.

Farther, next second time, when sched list is updated, the admin_sched
is not NULL and becomes the oper_sched, previous oper_sched was NULL so
just skipped. But then admin_sched is assigned new_admin, but schedules
to free previous assigned admin_sched (that already became oper_sched).

Farther, next third time, when sched list is updated,
while one more swap, oper_sched is not null, but it was happy to be
freed already (while prev. admin update), so while try to free
oper_sched the kernel panic happens at taprio_free_sched_cb().

So, move the "swap emulation" where it should be according to function
comment from code.

Fixes: 9c66d15646 ("taprio: Add support for hardware offloading")
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-05 13:58:14 -08:00
Yi Wang d665c1281b net: sched: taprio: fix -Wmissing-prototypes warnings
We get one warnings when build kernel W=1:
net/sched/sch_taprio.c:1155:6: warning: no previous prototype for ‘taprio_offload_config_changed’ [-Wmissing-prototypes]

Make the function static to fix this.

Fixes: 9c66d15646 ("taprio: Add support for hardware offloading")
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-22 13:35:07 -07:00
Vinicius Costa Gomes a954380acd net: taprio: Fix returning EINVAL when configuring without flags
When configuring a taprio instance if "flags" is not specified (or
it's zero), taprio currently replies with an "Invalid argument" error.

So, set the return value to zero after we are done with all the
checks.

Fixes: 9c66d15646 ("taprio: Add support for hardware offloading")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Acked-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-09 18:49:19 -07:00
Vladimir Oltean 9a9251a353 net: sched: taprio: Avoid division by zero on invalid link speed
The check in taprio_set_picos_per_byte is currently not robust enough
and will trigger this division by zero, due to e.g. PHYLINK not setting
kset->base.speed when there is no PHY connected:

[   27.109992] Division by zero in kernel.
[   27.113842] CPU: 1 PID: 198 Comm: tc Not tainted 5.3.0-rc5-01246-gc4006b8c2637-dirty #212
[   27.121974] Hardware name: Freescale LS1021A
[   27.126234] [<c03132e0>] (unwind_backtrace) from [<c030d8b8>] (show_stack+0x10/0x14)
[   27.133938] [<c030d8b8>] (show_stack) from [<c10b21b0>] (dump_stack+0xb0/0xc4)
[   27.141124] [<c10b21b0>] (dump_stack) from [<c10af97c>] (Ldiv0_64+0x8/0x18)
[   27.148052] [<c10af97c>] (Ldiv0_64) from [<c0700260>] (div64_u64+0xcc/0xf0)
[   27.154978] [<c0700260>] (div64_u64) from [<c07002d0>] (div64_s64+0x4c/0x68)
[   27.161993] [<c07002d0>] (div64_s64) from [<c0f3d890>] (taprio_set_picos_per_byte+0xe8/0xf4)
[   27.170388] [<c0f3d890>] (taprio_set_picos_per_byte) from [<c0f3f614>] (taprio_change+0x668/0xcec)
[   27.179302] [<c0f3f614>] (taprio_change) from [<c0f2bc24>] (qdisc_create+0x1fc/0x4f4)
[   27.187091] [<c0f2bc24>] (qdisc_create) from [<c0f2c0c8>] (tc_modify_qdisc+0x1ac/0x6f8)
[   27.195055] [<c0f2c0c8>] (tc_modify_qdisc) from [<c0ee9604>] (rtnetlink_rcv_msg+0x268/0x2dc)
[   27.203449] [<c0ee9604>] (rtnetlink_rcv_msg) from [<c0f4fef0>] (netlink_rcv_skb+0xe0/0x114)
[   27.211756] [<c0f4fef0>] (netlink_rcv_skb) from [<c0f4f6cc>] (netlink_unicast+0x1b4/0x22c)
[   27.219977] [<c0f4f6cc>] (netlink_unicast) from [<c0f4fa84>] (netlink_sendmsg+0x284/0x340)
[   27.228198] [<c0f4fa84>] (netlink_sendmsg) from [<c0eae5fc>] (sock_sendmsg+0x14/0x24)
[   27.235988] [<c0eae5fc>] (sock_sendmsg) from [<c0eaedf8>] (___sys_sendmsg+0x214/0x228)
[   27.243863] [<c0eaedf8>] (___sys_sendmsg) from [<c0eb015c>] (__sys_sendmsg+0x50/0x8c)
[   27.251652] [<c0eb015c>] (__sys_sendmsg) from [<c0301000>] (ret_fast_syscall+0x0/0x54)
[   27.259524] Exception stack(0xe8045fa8 to 0xe8045ff0)
[   27.264546] 5fa0:                   b6f608c8 000000f8 00000003 bed7e2f0 00000000 00000000
[   27.272681] 5fc0: b6f608c8 000000f8 004ce54c 00000128 5d3ce8c7 00000000 00000026 00505c9c
[   27.280812] 5fe0: 00000070 bed7e298 004ddd64 b6dd1e64

Russell King points out that the ethtool API says zero is a valid return
value of __ethtool_get_link_ksettings:

   * If it is enabled then they are read-only; if the link
   * is up they represent the negotiated link mode; if the link is down,
   * the speed is 0, %SPEED_UNKNOWN or the highest enabled speed and
   * @duplex is %DUPLEX_UNKNOWN or the best enabled duplex mode.

  So, it seems that taprio is not following the API... I'd suggest either
  fixing taprio, or getting agreement to change the ethtool API.

The chosen path was to fix taprio.

Fixes: 7b9eba7ba0 ("net/sched: taprio: fix picos_per_byte miscalculation")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-01 09:44:03 -07:00
Vladimir Oltean 68ce6688a5 net: sched: taprio: Fix potential integer overflow in taprio_set_picos_per_byte
The speed divisor is used in a context expecting an s64, but it is
evaluated using 32-bit arithmetic.

To avoid that happening, instead of multiplying by 1,000,000 in the
first place, simplify the fraction and do a standard 32 bit division
instead.

Fixes: f04b514c0c ("taprio: Set default link speed to 10 Mbps in taprio_set_picos_per_byte")
Reported-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-30 18:32:20 -07:00
Vinicius Costa Gomes 9c66d15646 taprio: Add support for hardware offloading
This allows taprio to offload the schedule enforcement to capable
network cards, resulting in more precise windows and less CPU usage.

The gate mask acts on traffic classes (groups of queues of same
priority), as specified in IEEE 802.1Q-2018, and following the existing
taprio and mqprio semantics.
It is up to the driver to perform conversion between tc and individual
netdev queues if for some reason it needs to make that distinction.

Full offload is requested from the network interface by specifying
"flags 2" in the tc qdisc creation command, which in turn corresponds to
the TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD bit.

The important detail here is the clockid which is implicitly /dev/ptpN
for full offload, and hence not configurable.

A reference counting API is added to support the use case where Ethernet
drivers need to keep the taprio offload structure locally (i.e. they are
a multi-port switch driver, and configuring a port depends on the
settings of other ports as well). The refcount_t variable is kept in a
private structure (__tc_taprio_qopt_offload) and not exposed to drivers.

In the future, the private structure might also be expanded with a
backpointer to taprio_sched *q, to implement the notification system
described in the patch (of when admin became oper, or an error occurred,
etc, so the offload can be monitored with 'tc qdisc show').

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Voon Weifeng <weifeng.voon@intel.com>
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-16 21:32:57 +02:00
David S. Miller 765b7590c9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
r8152 conflicts are the NAPI fixes in 'net' overlapping with
some tasklet stuff in net-next

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-02 11:20:17 -07:00
Vladimir Oltean f04b514c0c taprio: Set default link speed to 10 Mbps in taprio_set_picos_per_byte
The taprio budget needs to be adapted at runtime according to interface
link speed. But that handling is problematic.

For one thing, installing a qdisc on an interface that doesn't have
carrier is not illegal. But taprio prints the following stack trace:

[   31.851373] ------------[ cut here ]------------
[   31.856024] WARNING: CPU: 1 PID: 207 at net/sched/sch_taprio.c:481 taprio_dequeue+0x1a8/0x2d4
[   31.864566] taprio: dequeue() called with unknown picos per byte.
[   31.864570] Modules linked in:
[   31.873701] CPU: 1 PID: 207 Comm: tc Not tainted 5.3.0-rc5-01199-g8838fe023cd6 #1689
[   31.881398] Hardware name: Freescale LS1021A
[   31.885661] [<c03133a4>] (unwind_backtrace) from [<c030d8cc>] (show_stack+0x10/0x14)
[   31.893368] [<c030d8cc>] (show_stack) from [<c10ac958>] (dump_stack+0xb4/0xc8)
[   31.900555] [<c10ac958>] (dump_stack) from [<c0349d04>] (__warn+0xe0/0xf8)
[   31.907395] [<c0349d04>] (__warn) from [<c0349d64>] (warn_slowpath_fmt+0x48/0x6c)
[   31.914841] [<c0349d64>] (warn_slowpath_fmt) from [<c0f38db4>] (taprio_dequeue+0x1a8/0x2d4)
[   31.923150] [<c0f38db4>] (taprio_dequeue) from [<c0f227b0>] (__qdisc_run+0x90/0x61c)
[   31.930856] [<c0f227b0>] (__qdisc_run) from [<c0ec82ac>] (net_tx_action+0x12c/0x2bc)
[   31.938560] [<c0ec82ac>] (net_tx_action) from [<c0302298>] (__do_softirq+0x130/0x3c8)
[   31.946350] [<c0302298>] (__do_softirq) from [<c03502a0>] (irq_exit+0xbc/0xd8)
[   31.953536] [<c03502a0>] (irq_exit) from [<c03a4808>] (__handle_domain_irq+0x60/0xb4)
[   31.961328] [<c03a4808>] (__handle_domain_irq) from [<c0754478>] (gic_handle_irq+0x58/0x9c)
[   31.969638] [<c0754478>] (gic_handle_irq) from [<c0301a8c>] (__irq_svc+0x6c/0x90)
[   31.977076] Exception stack(0xe8167b20 to 0xe8167b68)
[   31.982100] 7b20: e9d4bd80 00000cc0 000000cf 00000000 e9d4bd80 c1f38958 00000cc0 c1f38960
[   31.990234] 7b40: 00000001 000000cf 00000004 e9dc0800 00000000 e8167b70 c0f478ec c0f46d94
[   31.998363] 7b60: 60070013 ffffffff
[   32.001833] [<c0301a8c>] (__irq_svc) from [<c0f46d94>] (netlink_trim+0x18/0xd8)
[   32.009104] [<c0f46d94>] (netlink_trim) from [<c0f478ec>] (netlink_broadcast_filtered+0x34/0x414)
[   32.017930] [<c0f478ec>] (netlink_broadcast_filtered) from [<c0f47cec>] (netlink_broadcast+0x20/0x28)
[   32.027102] [<c0f47cec>] (netlink_broadcast) from [<c0eea378>] (rtnetlink_send+0x34/0x88)
[   32.035238] [<c0eea378>] (rtnetlink_send) from [<c0f25890>] (notify_and_destroy+0x2c/0x44)
[   32.043461] [<c0f25890>] (notify_and_destroy) from [<c0f25e08>] (qdisc_graft+0x398/0x470)
[   32.051595] [<c0f25e08>] (qdisc_graft) from [<c0f27a00>] (tc_modify_qdisc+0x3a4/0x724)
[   32.059470] [<c0f27a00>] (tc_modify_qdisc) from [<c0ee4c84>] (rtnetlink_rcv_msg+0x260/0x2ec)
[   32.067864] [<c0ee4c84>] (rtnetlink_rcv_msg) from [<c0f4a988>] (netlink_rcv_skb+0xb8/0x110)
[   32.076172] [<c0f4a988>] (netlink_rcv_skb) from [<c0f4a170>] (netlink_unicast+0x1b4/0x22c)
[   32.084392] [<c0f4a170>] (netlink_unicast) from [<c0f4a5e4>] (netlink_sendmsg+0x33c/0x380)
[   32.092614] [<c0f4a5e4>] (netlink_sendmsg) from [<c0ea9f40>] (sock_sendmsg+0x14/0x24)
[   32.100403] [<c0ea9f40>] (sock_sendmsg) from [<c0eaa780>] (___sys_sendmsg+0x214/0x228)
[   32.108279] [<c0eaa780>] (___sys_sendmsg) from [<c0eabad0>] (__sys_sendmsg+0x50/0x8c)
[   32.116068] [<c0eabad0>] (__sys_sendmsg) from [<c0301000>] (ret_fast_syscall+0x0/0x54)
[   32.123938] Exception stack(0xe8167fa8 to 0xe8167ff0)
[   32.128960] 7fa0:                   b6fa68c8 000000f8 00000003 bea142d0 00000000 00000000
[   32.137093] 7fc0: b6fa68c8 000000f8 0052154c 00000128 5d6468a2 00000000 00000028 00558c9c
[   32.145224] 7fe0: 00000070 bea14278 00530d64 b6e17e64
[   32.150659] ---[ end trace 2139c9827c3e5177 ]---

This happens because the qdisc ->dequeue callback gets called. Which
again is not illegal, the qdisc will dequeue even when the interface is
up but doesn't have carrier (and hence SPEED_UNKNOWN), and the frames
will be dropped further down the stack in dev_direct_xmit().

And, at the end of the day, for what? For calculating the initial budget
of an interface which is non-operational at the moment and where frames
will get dropped anyway.

So if we can't figure out the link speed, default to SPEED_10 and move
along. We can also remove the runtime check now.

Cc: Leandro Dorileo <leandro.maciel.dorileo@intel.com>
Fixes: 7b9eba7ba0 ("net/sched: taprio: fix picos_per_byte miscalculation")
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-31 18:45:34 -07:00
Vladimir Oltean efb55222d3 taprio: Fix kernel panic in taprio_destroy
taprio_init may fail earlier than this line:

	list_add(&q->taprio_list, &taprio_list);

i.e. due to the net device not being multi queue.

Attempting to remove q from the global taprio_list when it is not part
of it will result in a kernel panic.

Fix it by matching list_add and list_del better to one another in the
order of operations. This way we can keep the deletion unconditional
and with lower complexity - O(1).

Cc: Leandro Dorileo <leandro.maciel.dorileo@intel.com>
Fixes: 7b9eba7ba0 ("net/sched: taprio: fix picos_per_byte miscalculation")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-31 18:45:34 -07:00
David S. Miller 446bf64b61 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge conflict of mlx5 resolved using instructions in merge
commit 9566e650bf.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-19 11:54:03 -07:00
YueHaibing ca497fb6aa taprio: remove unused variable 'entry_list_policy'
net/sched/sch_taprio.c:680:32: warning:
 entry_list_policy defined but not used [-Wunused-const-variable=]

One of the points of commit a3d43c0d56 ("taprio: Add support adding
an admin schedule") is that it removes support (it now returns "not
supported") for schedules using the TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY
attribute (which were never used), the parsing of those types of schedules
was the only user of this policy. So removing this policy should be fine.

Reported-by: Hulk Robot <hulkci@huawei.com>
Suggested-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-09 13:41:24 -07:00
Ivan Khoronzhuk 51650d33b2 net: sched: sch_taprio: fix memleak in error path for sched list parse
In error case, all entries should be freed from the sched list
before deleting it. For simplicity use rcu way.

Fixes: 5a781ccbd1 ("tc: Add support for configuring the taprio scheduler")
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-08 22:00:24 -07:00
Vedang Patel a5b647007e fix: taprio: Change type of txtime-delay parameter to u32
During the review of the iproute2 patches for txtime-assist mode, it was
pointed out that it does not make sense for the txtime-delay parameter to
be negative. So, change the type of the parameter from s32 to u32.

Fixes: 4cfd5779bd ("taprio: Add support for txtime-assist mode")
Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-16 14:19:19 -07:00
Vedang Patel 5400206610 taprio: Adjust timestamps for TCP packets
When the taprio qdisc is running in "txtime offload" mode, it will
set the launchtime value (in skb->tstamp) for all the packets which do
not have the SO_TXTIME socket option. But, the TCP packets already have
this value set and it indicates the earliest departure time represented
in CLOCK_MONOTONIC clock.

We need to respect the timestamp set by the TCP subsystem. So, convert
this time to the clock which taprio is using and ensure that the packet
is not transmitted before the deadline set by TCP.

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-28 14:45:34 -07:00
Vedang Patel 7ede7b0348 taprio: make clock reference conversions easier
Later in this series we will need to transform from
CLOCK_MONOTONIC (used in TCP) to the clock reference used in TAPRIO.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-28 14:45:34 -07:00
Vedang Patel 4cfd5779bd taprio: Add support for txtime-assist mode
Currently, we are seeing non-critical packets being transmitted outside of
their timeslice. We can confirm that the packets are being dequeued at the
right time. So, the delay is induced in the hardware side.  The most likely
reason is the hardware queues are starving the lower priority queues.

In order to improve the performance of taprio, we will be making use of the
txtime feature provided by the ETF qdisc. For all the packets which do not
have the SO_TXTIME option set, taprio will set the transmit timestamp (set
in skb->tstamp) in this mode. TAPrio Qdisc will ensure that the transmit
time for the packet is set to when the gate is open. If SO_TXTIME is set,
the TAPrio qdisc will validate whether the timestamp (in skb->tstamp)
occurs when the gate corresponding to skb's traffic class is open.

Following two parameters added to support this mode:
- flags: used to enable txtime-assist mode. Will also be used to enable
  other modes (like hardware offloading) later.
- txtime-delay: This indicates the minimum time it will take for the packet
  to hit the wire. This is useful in determining whether we can transmit
the packet in the remaining time if the gate corresponding to the packet is
currently open.

An example configuration for enabling txtime-assist:

tc qdisc replace dev eth0 parent root handle 100 taprio \\
      num_tc 3 \\
      map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \\
      queues 1@0 1@0 1@0 \\
      base-time 1558653424279842568 \\
      sched-entry S 01 300000 \\
      sched-entry S 02 300000 \\
      sched-entry S 04 400000 \\
      flags 0x1 \\
      txtime-delay 40000 \\
      clockid CLOCK_TAI

tc qdisc replace dev $IFACE parent 100:1 etf skip_sock_check \\
      offload delta 200000 clockid CLOCK_TAI

Note that all the traffic classes are mapped to the same queue.  This is
only possible in taprio when txtime-assist is enabled. Also, note that the
ETF Qdisc is enabled with offload mode set.

In this mode, if the packet's traffic class is open and the complete packet
can be transmitted, taprio will try to transmit the packet immediately.
This will be done by setting skb->tstamp to current_time + the time delta
indicated in the txtime-delay parameter. This parameter indicates the time
taken (in software) for packet to reach the network adapter.

If the packet cannot be transmitted in the current interval or if the
packet's traffic is not currently transmitting, the skb->tstamp is set to
the next available timestamp value. This is tracked in the next_launchtime
parameter in the struct sched_entry.

The behaviour w.r.t admin and oper schedules is not changed from what is
present in software mode.

The transmit time is already known in advance. So, we do not need the HR
timers to advance the schedule and wakeup the dequeue side of taprio.  So,
HR timer won't be run when this mode is enabled.

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-28 14:45:34 -07:00
Vedang Patel 566af331b5 taprio: Remove inline directive
Remove inline directive from length_to_duration(). We will let the compiler
make the decisions.

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-28 14:45:34 -07:00
Vedang Patel 037be03740 taprio: calculate cycle_time when schedule is installed
cycle time for a particular schedule is calculated only when it is first
installed. So, it makes sense to just calculate it once right after the
'cycle_time' parameter has been parsed and store it in cycle_time.

Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-28 14:45:33 -07:00
Colin Ian King e4acf42741 taprio: add null check on sched_nest to avoid potential null pointer dereference
The call to nla_nest_start_noflag can return a null pointer and currently
this is not being checked and this can lead to a null pointer dereference
when the null pointer sched_nest is passed to function nla_nest_end. Fix
this by adding in a null pointer check.

Addresses-Coverity: ("Dereference null return value")
Fixes: a3d43c0d56 ("taprio: Add support adding an admin schedule")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-07 12:15:33 -07:00
Vinicius Costa Gomes c25031e993 taprio: Add support for cycle-time-extension
IEEE 802.1Q-2018 defines the concept of a cycle-time-extension, so the
last entry of a schedule before the start of a new schedule can be
extended, so "too-short" entries can be avoided.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-01 11:58:51 -04:00
Vinicius Costa Gomes 6ca6a66542 taprio: Add support for setting the cycle-time manually
IEEE 802.1Q-2018 defines that a the cycle-time of a schedule may be
overridden, so the schedule is truncated to a determined "width".

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-01 11:58:51 -04:00
Vinicius Costa Gomes a3d43c0d56 taprio: Add support adding an admin schedule
The IEEE 802.1Q-2018 defines two "types" of schedules, the "Oper" (from
operational?) and "Admin" ones. Up until now, 'taprio' only had
support for the "Oper" one, added when the qdisc is created. This adds
support for the "Admin" one, which allows the .change() operation to
be supported.

Just for clarification, some quick (and dirty) definitions, the "Oper"
schedule is the currently (as in this instant) running one, and it's
read-only. The "Admin" one is the one that the system configurator has
installed, it can be changed, and it will be "promoted" to "Oper" when
it's 'base-time' is reached.

The idea behing this patch is that calling something like the below,
(after taprio is already configured with an initial schedule):

$ tc qdisc change taprio dev IFACE parent root 	     \
     	   base-time X 	     	   	       	     \
     	   sched-entry <CMD> <GATES> <INTERVAL>	     \
	   ...

Will cause a new admin schedule to be created and programmed to be
"promoted" to "Oper" at instant X. If an "Admin" schedule already
exists, it will be overwritten with the new parameters.

Up until now, there was some code that was added to ease the support
of changing a single entry of a schedule, but was ultimately unused.
Now, that we have support for "change" with more well thought
semantics, updating a single entry seems to be less useful.

So we remove what is in practice dead code, and return a "not
supported" error if the user tries to use it. If changing a single
entry would make the user's life easier we may ressurrect this idea,
but at this point, removing it simplifies the code.

For now, only the schedule specific bits are allowed to be added for a
new schedule, that means that 'clockid', 'num_tc', 'map' and 'queues'
cannot be modified.

Example:

$ tc qdisc change dev IFACE parent root handle 100 taprio \
      base-time $BASE_TIME \
      sched-entry S 00 500000 \
      sched-entry S 0f 500000 \
      clockid CLOCK_TAI

The only change in the netlink API introduced by this change is the
introduction of an "admin" type in the response to a dump request,
that type allows userspace to separate the "oper" schedule from the
"admin" schedule. If userspace doesn't support the "admin" type, it
will only display the "oper" schedule.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-01 11:58:51 -04:00
Vinicius Costa Gomes 8c79f0ea5d taprio: Fix potencial use of invalid memory during dequeue()
Right now, this isn't a problem, but the next commit allows schedules
to be added during runtime. When a new schedule transitions from the
inactive to the active state ("admin" -> "oper") the previous one can
be freed, if it's freed just after the RCU read lock is released, we
may access an invalid entry.

So, we should take care to protect the dequeue() flow, so all the
places that access the entries are protected by the RCU read lock.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-01 11:58:51 -04:00
Johannes Berg 8cb081746c netlink: make validation more configurable for future strictness
We currently have two levels of strict validation:

 1) liberal (default)
     - undefined (type >= max) & NLA_UNSPEC attributes accepted
     - attribute length >= expected accepted
     - garbage at end of message accepted
 2) strict (opt-in)
     - NLA_UNSPEC attributes accepted
     - attribute length >= expected accepted

Split out parsing strictness into four different options:
 * TRAILING     - check that there's no trailing data after parsing
                  attributes (in message or nested)
 * MAXTYPE      - reject attrs > max known type
 * UNSPEC       - reject attributes with NLA_UNSPEC policy entries
 * STRICT_ATTRS - strictly validate attribute size

The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().

Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.

We end up with the following renames:
 * nla_parse           -> nla_parse_deprecated
 * nla_parse_strict    -> nla_parse_deprecated_strict
 * nlmsg_parse         -> nlmsg_parse_deprecated
 * nlmsg_parse_strict  -> nlmsg_parse_deprecated_strict
 * nla_parse_nested    -> nla_parse_nested_deprecated
 * nla_validate_nested -> nla_validate_nested_deprecated

Using spatch, of course:
    @@
    expression TB, MAX, HEAD, LEN, POL, EXT;
    @@
    -nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
    +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)

    @@
    expression NLH, HDRLEN, TB, MAX, POL, EXT;
    @@
    -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
    +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)

    @@
    expression NLH, HDRLEN, TB, MAX, POL, EXT;
    @@
    -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
    +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)

    @@
    expression TB, MAX, NLA, POL, EXT;
    @@
    -nla_parse_nested(TB, MAX, NLA, POL, EXT)
    +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)

    @@
    expression START, MAX, POL, EXT;
    @@
    -nla_validate_nested(START, MAX, POL, EXT)
    +nla_validate_nested_deprecated(START, MAX, POL, EXT)

    @@
    expression NLH, HDRLEN, MAX, POL, EXT;
    @@
    -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
    +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)

For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.

Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.

Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.

In effect then, this adds fully strict validation for any new command.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27 17:07:21 -04:00
Michal Kubecek ae0be8de9a netlink: make nla_nest_start() add NLA_F_NESTED flag
Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most
netlink based interfaces (including recently added ones) are still not
setting it in kernel generated messages. Without the flag, message parsers
not aware of attribute semantics (e.g. wireshark dissector or libmnl's
mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display
the structure of their contents.

Unfortunately we cannot just add the flag everywhere as there may be
userspace applications which check nlattr::nla_type directly rather than
through a helper masking out the flags. Therefore the patch renames
nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start()
as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually
are rewritten to use nla_nest_start().

Except for changes in include/net/netlink.h, the patch was generated using
this semantic patch:

@@ expression E1, E2; @@
-nla_nest_start(E1, E2)
+nla_nest_start_noflag(E1, E2)

@@ expression E1, E2; @@
-nla_nest_start_noflag(E1, E2 | NLA_F_NESTED)
+nla_nest_start(E1, E2)

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27 17:03:44 -04:00
Andre Guedes 6e734c82be net: sched: taprio: Fix taprio_dequeue()
In case we don't have 'guard' or 'budget' to transmit the skb, we should
continue traversing the qdisc list since the remaining guard/budget
might be enough to transmit a skb from other children qdiscs.

Fixes: 5a781ccbd1 (“tc: Add support for configuring the taprio scheduler”)
Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-23 19:52:32 -07:00
Andre Guedes 2684d1b75f net: sched: taprio: Fix taprio_peek()
While traversing taprio's children qdisc list, if the gate is closed for
a given traffic class, we should continue traversing the list since the
remaining qdiscs may have skb ready for transmission.

This patch also takes this opportunity and changes the function to use
the TAPRIO_ALL_GATES_OPEN macro instead of the magic number '-1'.

Fixes: 5a781ccbd1 (“tc: Add support for configuring the taprio scheduler”)
Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-23 19:52:32 -07:00
Andre Guedes 5175aafe71 net: sched: taprio: Remove should_restart_cycle()
The 'entry' argument from should_restart_cycle() cannot be NULL since it
is already checked by the caller so the WARN_ON() within should_
restart_cycle() could be removed.  By doing that, that function becomes
a dummy wrapper on list_is_last() so this patch simply gets rid of it
and call list_is_last() within advance_sched() instead.

Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-23 19:52:32 -07:00
Andre Guedes 8599099f0c net: sched: taprio: Refactor taprio_get_start_time()
This patch does a code refactoring to taprio_get_start_time() function
to improve readability and report error properly.

If 'base' time is later than 'now', the start time is equal to 'base'
and taprio_get_start_time() is done. That's the natural case so we move
that code to the beginning of the function. Also, if 'cycle' calculation
is zero, something went really wrong with taprio and we should log that
internal error properly.

Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-23 19:52:32 -07:00
Andre Guedes 59ab87f6eb net: sched: taprio: Remove pointless variable assigment
This patch removes a pointless variable assigment in taprio_change().
The 'err' variable is not used from this assignment to the next one so
this patch removes it.

Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-23 19:52:32 -07:00
Jakub Kicinski 23bddf692d net/sched: taprio: fix build without 64bit div
Recent changes to taprio did not use the correct div64 helpers,
leading to:

net/sched/sch_taprio.o: In function `taprio_dequeue':
sch_taprio.c:(.text+0x34a): undefined reference to `__divdi3'
net/sched/sch_taprio.o: In function `advance_sched':
sch_taprio.c:(.text+0xa0b): undefined reference to `__divdi3'
net/sched/sch_taprio.o: In function `taprio_init':
sch_taprio.c:(.text+0x1450): undefined reference to `__divdi3'
/home/jkicinski/devel/linux/Makefile:1032: recipe for target 'vmlinux' failed

Use math64 helpers.

Fixes: 7b9eba7ba0 ("net/sched: taprio: fix picos_per_byte miscalculation")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-18 17:06:15 -07:00
Leandro Dorileo 7b9eba7ba0 net/sched: taprio: fix picos_per_byte miscalculation
The Time Aware Priority Scheduler is heavily dependent to link speed,
it relies on it to calculate transmission bytes per cycle, we can't
properly calculate the so called budget if the device has failed
to report the link speed.

In that case we can't dequeue packets assuming a wrong budget.
This patch makes sure we fail to dequeue case:

1) __ethtool_get_link_ksettings() reports error or 2) the ethernet
driver failed to set the ksettings' speed value (setting link speed
to SPEED_UNKNOWN).

Additionally we re calculate the budget whenever the link speed is
changed.

Fixes: 5a781ccbd1 ("tc: Add support for configuring the taprio scheduler")
Signed-off-by: Leandro Dorileo <leandro.maciel.dorileo@intel.com>
Reviewed-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-10 19:27:43 -07:00
Paolo Abeni 5dd431b6b9 net: sched: introduce and use qstats read helpers
Classful qdiscs can't access directly the child qdiscs backlog
length: if such qdisc is NOLOCK, per CPU values should be
accounted instead.

Most qdiscs no not respect the above. As a result, qstats fetching
for most classful qdisc is currently incorrect: if the child qdisc is
NOLOCK, it always reports 0 len backlog.

This change introduces a pair of helpers to safely fetch
both backlog and qlen and use them in stats class dumping
functions, fixing the above issue and cleaning a bit the code.

DRR needs also to access the child qdisc queue length, so it
needs custom handling.

Fixes: c5ad119fb6 ("net: sched: pfifo_fast use skb_array")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-01 14:50:13 -07:00
Vinicius Costa Gomes 5a781ccbd1 tc: Add support for configuring the taprio scheduler
This traffic scheduler allows traffic classes states (transmission
allowed/not allowed, in the simplest case) to be scheduled, according
to a pre-generated time sequence. This is the basis of the IEEE
802.1Qbv specification.

Example configuration:

tc qdisc replace dev enp3s0 parent root handle 100 taprio \
          num_tc 3 \
	  map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \
	  queues 1@0 1@1 2@2 \
	  base-time 1528743495910289987 \
	  sched-entry S 01 300000 \
	  sched-entry S 02 300000 \
	  sched-entry S 04 300000 \
	  clockid CLOCK_TAI

The configuration format is similar to mqprio. The main difference is
the presence of a schedule, built by multiple "sched-entry"
definitions, each entry has the following format:

     sched-entry <CMD> <GATE MASK> <INTERVAL>

The only supported <CMD> is "S", which means "SetGateStates",
following the IEEE 802.1Qbv-2015 definition (Table 8-6). <GATE MASK>
is a bitmask where each bit is a associated with a traffic class, so
bit 0 (the least significant bit) being "on" means that traffic class
0 is "active" for that schedule entry. <INTERVAL> is a time duration
in nanoseconds that specifies for how long that state defined by <CMD>
and <GATE MASK> should be held before moving to the next entry.

This schedule is circular, that is, after the last entry is executed
it starts from the first one, indefinitely.

The other parameters can be defined as follows:

 - base-time: specifies the instant when the schedule starts, if
  'base-time' is a time in the past, the schedule will start at

 	      base-time + (N * cycle-time)

   where N is the smallest integer so the resulting time is greater
   than "now", and "cycle-time" is the sum of all the intervals of the
   entries in the schedule;

 - clockid: specifies the reference clock to be used;

The parameters should be similar to what the IEEE 802.1Q family of
specification defines.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-04 13:52:23 -07:00