1. 23 11月, 2018 1 次提交
    • E
      net-gro: reset skb->pkt_type in napi_reuse_skb() · a21a82a9
      Eric Dumazet 提交于
      [ Upstream commit 33d9a2c72f086cbf1087b2fd2d1a15aa9df14a7f ]
      
      eth_type_trans() assumes initial value for skb->pkt_type
      is PACKET_HOST.
      
      This is indeed the value right after a fresh skb allocation.
      
      However, it is possible that GRO merged a packet with a different
      value (like PACKET_OTHERHOST in case macvlan is used), so
      we need to make sure napi->skb will have pkt_type set back to
      PACKET_HOST.
      
      Otherwise, valid packets might be dropped by the stack because
      their pkt_type is not PACKET_HOST.
      
      napi_reuse_skb() was added in commit 96e93eab ("gro: Add
      internal interfaces for VLAN"), but this bug always has
      been there.
      
      Fixes: 96e93eab ("gro: Add internal interfaces for VLAN")
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      a21a82a9
  2. 04 11月, 2018 1 次提交
  3. 11 10月, 2018 1 次提交
    • S
      net: ipv4: update fnhe_pmtu when first hop's MTU changes · af7d6cce
      Sabrina Dubroca 提交于
      Since commit 5aad1de5 ("ipv4: use separate genid for next hop
      exceptions"), exceptions get deprecated separately from cached
      routes. In particular, administrative changes don't clear PMTU anymore.
      
      As Stefano described in commit e9fa1495 ("ipv6: Reflect MTU changes
      on PMTU of exceptions for MTU-less routes"), the PMTU discovered before
      the local MTU change can become stale:
       - if the local MTU is now lower than the PMTU, that PMTU is now
         incorrect
       - if the local MTU was the lowest value in the path, and is increased,
         we might discover a higher PMTU
      
      Similarly to what commit e9fa1495 did for IPv6, update PMTU in those
      cases.
      
      If the exception was locked, the discovered PMTU was smaller than the
      minimal accepted PMTU. In that case, if the new local MTU is smaller
      than the current PMTU, let PMTU discovery figure out if locking of the
      exception is still needed.
      
      To do this, we need to know the old link MTU in the NETDEV_CHANGEMTU
      notifier. By the time the notifier is called, dev->mtu has been
      changed. This patch adds the old MTU as additional information in the
      notifier structure, and a new call_netdevice_notifiers_u32() function.
      
      Fixes: 5aad1de5 ("ipv4: use separate genid for next hop exceptions")
      Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
      Reviewed-by: NStefano Brivio <sbrivio@redhat.com>
      Reviewed-by: NDavid Ahern <dsahern@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      af7d6cce
  4. 30 8月, 2018 1 次提交
  5. 10 8月, 2018 1 次提交
    • A
      net: allow to call netif_reset_xps_queues() under cpus_read_lock · 4d99f660
      Andrei Vagin 提交于
      The definition of static_key_slow_inc() has cpus_read_lock in place. In the
      virtio_net driver, XPS queues are initialized after setting the queue:cpu
      affinity in virtnet_set_affinity() which is already protected within
      cpus_read_lock. Lockdep prints a warning when we are trying to acquire
      cpus_read_lock when it is already held.
      
      This patch adds an ability to call __netif_set_xps_queue under
      cpus_read_lock().
      Acked-by: NJason Wang <jasowang@redhat.com>
      
      ============================================
      WARNING: possible recursive locking detected
      4.18.0-rc3-next-20180703+ #1 Not tainted
      --------------------------------------------
      swapper/0/1 is trying to acquire lock:
      00000000cf973d46 (cpu_hotplug_lock.rw_sem){++++}, at: static_key_slow_inc+0xe/0x20
      
      but task is already holding lock:
      00000000cf973d46 (cpu_hotplug_lock.rw_sem){++++}, at: init_vqs+0x513/0x5a0
      
      other info that might help us debug this:
       Possible unsafe locking scenario:
      
             CPU0
             ----
        lock(cpu_hotplug_lock.rw_sem);
        lock(cpu_hotplug_lock.rw_sem);
      
       *** DEADLOCK ***
      
       May be due to missing lock nesting notation
      
      3 locks held by swapper/0/1:
       #0: 00000000244bc7da (&dev->mutex){....}, at: __driver_attach+0x5a/0x110
       #1: 00000000cf973d46 (cpu_hotplug_lock.rw_sem){++++}, at: init_vqs+0x513/0x5a0
       #2: 000000005cd8463f (xps_map_mutex){+.+.}, at: __netif_set_xps_queue+0x8d/0xc60
      
      v2: move cpus_read_lock() out of __netif_set_xps_queue()
      
      Cc: "Nambiar, Amritha" <amritha.nambiar@intel.com>
      Cc: "Michael S. Tsirkin" <mst@redhat.com>
      Cc: Jason Wang <jasowang@redhat.com>
      Fixes: 8af2c06f ("net-sysfs: Add interface for Rx queue(s) map per Tx queue")
      Signed-off-by: NAndrei Vagin <avagin@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4d99f660
  6. 06 8月, 2018 1 次提交
  7. 31 7月, 2018 1 次提交
    • P
      net/tc: introduce TC_ACT_REINSERT. · cd11b164
      Paolo Abeni 提交于
      This is similar TC_ACT_REDIRECT, but with a slightly different
      semantic:
      - on ingress the mirred skbs are passed to the target device
      network stack without any additional check not scrubbing.
      - the rcu-protected stats provided via the tcf_result struct
        are updated on error conditions.
      
      This new tcfa_action value is not exposed to the user-space
      and can be used only internally by clsact.
      
      v1 -> v2: do not touch TC_ACT_REDIRECT code path, introduce
       a new action type instead
      v2 -> v3:
       - rename the new action value TC_ACT_REINJECT, update the
         helper accordingly
       - take care of uncloned reinjected packets in XDP generic
         hook
      v3 -> v4:
       - renamed again the new action value (JiriP)
      v4 -> v5:
       - fix build error with !NET_CLS_ACT (kbuild bot)
      Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
      Acked-by: NJiri Pirko <jiri@mellanox.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      cd11b164
  8. 30 7月, 2018 1 次提交
  9. 27 7月, 2018 1 次提交
  10. 21 7月, 2018 1 次提交
  11. 17 7月, 2018 2 次提交
  12. 14 7月, 2018 2 次提交
  13. 13 7月, 2018 1 次提交
    • P
      net: gro: properly remove skb from list · 68d2f84a
      Prashant Bhole 提交于
      Following crash occurs in validate_xmit_skb_list() when same skb is
      iterated multiple times in the loop and consume_skb() is called.
      
      The root cause is calling list_del_init(&skb->list) and not clearing
      skb->next in d4546c25. list_del_init(&skb->list) sets skb->next
      to point to skb itself. skb->next needs to be cleared because other
      parts of network stack uses another kind of SKB lists.
      validate_xmit_skb_list() uses such list.
      
      A similar type of bugfix was reported by Jesper Dangaard Brouer.
      https://patchwork.ozlabs.org/patch/942541/
      
      This patch clears skb->next and changes list_del_init() to list_del()
      so that list->prev will maintain the list poison.
      
      [  148.185511] ==================================================================
      [  148.187865] BUG: KASAN: use-after-free in validate_xmit_skb_list+0x4b/0xa0
      [  148.190158] Read of size 8 at addr ffff8801e52eefc0 by task swapper/1/0
      [  148.192940]
      [  148.193642] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.18.0-rc3+ #25
      [  148.195423] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20180531_142017-buildhw-08.phx2.fedoraproject.org-1.fc28 04/01/2014
      [  148.199129] Call Trace:
      [  148.200565]  <IRQ>
      [  148.201911]  dump_stack+0xc6/0x14c
      [  148.203572]  ? dump_stack_print_info.cold.1+0x2f/0x2f
      [  148.205083]  ? kmsg_dump_rewind_nolock+0x59/0x59
      [  148.206307]  ? validate_xmit_skb+0x2c6/0x560
      [  148.207432]  ? debug_show_held_locks+0x30/0x30
      [  148.208571]  ? validate_xmit_skb_list+0x4b/0xa0
      [  148.211144]  print_address_description+0x6c/0x23c
      [  148.212601]  ? validate_xmit_skb_list+0x4b/0xa0
      [  148.213782]  kasan_report.cold.6+0x241/0x2fd
      [  148.214958]  validate_xmit_skb_list+0x4b/0xa0
      [  148.216494]  sch_direct_xmit+0x1b0/0x680
      [  148.217601]  ? dev_watchdog+0x4e0/0x4e0
      [  148.218675]  ? do_raw_spin_trylock+0x10/0x120
      [  148.219818]  ? do_raw_spin_lock+0xe0/0xe0
      [  148.221032]  __dev_queue_xmit+0x1167/0x1810
      [  148.222155]  ? sched_clock+0x5/0x10
      [...]
      
      [  148.474257] Allocated by task 0:
      [  148.475363]  kasan_kmalloc+0xbf/0xe0
      [  148.476503]  kmem_cache_alloc+0xb4/0x1b0
      [  148.477654]  __build_skb+0x91/0x250
      [  148.478677]  build_skb+0x67/0x180
      [  148.479657]  e1000_clean_rx_irq+0x542/0x8a0
      [  148.480757]  e1000_clean+0x652/0xd10
      [  148.481772]  net_rx_action+0x4ea/0xc20
      [  148.482808]  __do_softirq+0x1f9/0x574
      [  148.483831]
      [  148.484575] Freed by task 0:
      [  148.485504]  __kasan_slab_free+0x12e/0x180
      [  148.486589]  kmem_cache_free+0xb4/0x240
      [  148.487634]  kfree_skbmem+0xed/0x150
      [  148.488648]  consume_skb+0x146/0x250
      [  148.489665]  validate_xmit_skb+0x2b7/0x560
      [  148.490754]  validate_xmit_skb_list+0x70/0xa0
      [  148.491897]  sch_direct_xmit+0x1b0/0x680
      [  148.493949]  __dev_queue_xmit+0x1167/0x1810
      [  148.495103]  br_dev_queue_push_xmit+0xce/0x250
      [  148.496196]  br_forward_finish+0x276/0x280
      [  148.497234]  __br_forward+0x44f/0x520
      [  148.498260]  br_forward+0x19f/0x1b0
      [  148.499264]  br_handle_frame_finish+0x65e/0x980
      [  148.500398]  NF_HOOK.constprop.10+0x290/0x2a0
      [  148.501522]  br_handle_frame+0x417/0x640
      [  148.502582]  __netif_receive_skb_core+0xaac/0x18f0
      [  148.503753]  __netif_receive_skb_one_core+0x98/0x120
      [  148.504958]  netif_receive_skb_internal+0xe3/0x330
      [  148.506154]  napi_gro_complete+0x190/0x2a0
      [  148.507243]  dev_gro_receive+0x9f7/0x1100
      [  148.508316]  napi_gro_receive+0xcb/0x260
      [  148.509387]  e1000_clean_rx_irq+0x2fc/0x8a0
      [  148.510501]  e1000_clean+0x652/0xd10
      [  148.511523]  net_rx_action+0x4ea/0xc20
      [  148.512566]  __do_softirq+0x1f9/0x574
      [  148.513598]
      [  148.514346] The buggy address belongs to the object at ffff8801e52eefc0
      [  148.514346]  which belongs to the cache skbuff_head_cache of size 232
      [  148.517047] The buggy address is located 0 bytes inside of
      [  148.517047]  232-byte region [ffff8801e52eefc0, ffff8801e52ef0a8)
      [  148.519549] The buggy address belongs to the page:
      [  148.520726] page:ffffea000794bb00 count:1 mapcount:0 mapping:ffff880106f4dfc0 index:0xffff8801e52ee840 compound_mapcount: 0
      [  148.524325] flags: 0x17ffffc0008100(slab|head)
      [  148.525481] raw: 0017ffffc0008100 ffff880106b938d0 ffff880106b938d0 ffff880106f4dfc0
      [  148.527503] raw: ffff8801e52ee840 0000000000190011 00000001ffffffff 0000000000000000
      [  148.529547] page dumped because: kasan: bad access detected
      
      Fixes: d4546c25 ("net: Convert GRO SKB handling to list_head.")
      Signed-off-by: NPrashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
      Reported-by: NTyler Hicks <tyhicks@canonical.com>
      Tested-by: NTyler Hicks <tyhicks@canonical.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      68d2f84a
  14. 10 7月, 2018 7 次提交
  15. 05 7月, 2018 1 次提交
  16. 04 7月, 2018 7 次提交
  17. 02 7月, 2018 3 次提交
  18. 26 6月, 2018 2 次提交
  19. 20 6月, 2018 1 次提交
  20. 13 6月, 2018 1 次提交
    • K
      treewide: kmalloc() -> kmalloc_array() · 6da2ec56
      Kees Cook 提交于
      The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
      patch replaces cases of:
      
              kmalloc(a * b, gfp)
      
      with:
              kmalloc_array(a * b, gfp)
      
      as well as handling cases of:
      
              kmalloc(a * b * c, gfp)
      
      with:
      
              kmalloc(array3_size(a, b, c), gfp)
      
      as it's slightly less ugly than:
      
              kmalloc_array(array_size(a, b), c, gfp)
      
      This does, however, attempt to ignore constant size factors like:
      
              kmalloc(4 * 1024, gfp)
      
      though any constants defined via macros get caught up in the conversion.
      
      Any factors with a sizeof() of "unsigned char", "char", and "u8" were
      dropped, since they're redundant.
      
      The tools/ directory was manually excluded, since it has its own
      implementation of kmalloc().
      
      The Coccinelle script used for this was:
      
      // Fix redundant parens around sizeof().
      @@
      type TYPE;
      expression THING, E;
      @@
      
      (
        kmalloc(
      -	(sizeof(TYPE)) * E
      +	sizeof(TYPE) * E
        , ...)
      |
        kmalloc(
      -	(sizeof(THING)) * E
      +	sizeof(THING) * E
        , ...)
      )
      
      // Drop single-byte sizes and redundant parens.
      @@
      expression COUNT;
      typedef u8;
      typedef __u8;
      @@
      
      (
        kmalloc(
      -	sizeof(u8) * (COUNT)
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(__u8) * (COUNT)
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(char) * (COUNT)
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(unsigned char) * (COUNT)
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(u8) * COUNT
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(__u8) * COUNT
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(char) * COUNT
      +	COUNT
        , ...)
      |
        kmalloc(
      -	sizeof(unsigned char) * COUNT
      +	COUNT
        , ...)
      )
      
      // 2-factor product with sizeof(type/expression) and identifier or constant.
      @@
      type TYPE;
      expression THING;
      identifier COUNT_ID;
      constant COUNT_CONST;
      @@
      
      (
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * (COUNT_ID)
      +	COUNT_ID, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * COUNT_ID
      +	COUNT_ID, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * (COUNT_CONST)
      +	COUNT_CONST, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * COUNT_CONST
      +	COUNT_CONST, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * (COUNT_ID)
      +	COUNT_ID, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * COUNT_ID
      +	COUNT_ID, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * (COUNT_CONST)
      +	COUNT_CONST, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * COUNT_CONST
      +	COUNT_CONST, sizeof(THING)
        , ...)
      )
      
      // 2-factor product, only identifiers.
      @@
      identifier SIZE, COUNT;
      @@
      
      - kmalloc
      + kmalloc_array
        (
      -	SIZE * COUNT
      +	COUNT, SIZE
        , ...)
      
      // 3-factor product with 1 sizeof(type) or sizeof(expression), with
      // redundant parens removed.
      @@
      expression THING;
      identifier STRIDE, COUNT;
      type TYPE;
      @@
      
      (
        kmalloc(
      -	sizeof(TYPE) * (COUNT) * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE) * (COUNT) * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE) * COUNT * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE) * COUNT * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(TYPE))
        , ...)
      |
        kmalloc(
      -	sizeof(THING) * (COUNT) * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        kmalloc(
      -	sizeof(THING) * (COUNT) * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        kmalloc(
      -	sizeof(THING) * COUNT * (STRIDE)
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      |
        kmalloc(
      -	sizeof(THING) * COUNT * STRIDE
      +	array3_size(COUNT, STRIDE, sizeof(THING))
        , ...)
      )
      
      // 3-factor product with 2 sizeof(variable), with redundant parens removed.
      @@
      expression THING1, THING2;
      identifier COUNT;
      type TYPE1, TYPE2;
      @@
      
      (
        kmalloc(
      -	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
        , ...)
      |
        kmalloc(
      -	sizeof(THING1) * sizeof(THING2) * COUNT
      +	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
        , ...)
      |
        kmalloc(
      -	sizeof(THING1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * COUNT
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
        , ...)
      |
        kmalloc(
      -	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
      +	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
        , ...)
      )
      
      // 3-factor product, only identifiers, with redundant parens removed.
      @@
      identifier STRIDE, SIZE, COUNT;
      @@
      
      (
        kmalloc(
      -	(COUNT) * STRIDE * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	COUNT * (STRIDE) * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	COUNT * STRIDE * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	(COUNT) * (STRIDE) * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	COUNT * (STRIDE) * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	(COUNT) * STRIDE * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	(COUNT) * (STRIDE) * (SIZE)
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      |
        kmalloc(
      -	COUNT * STRIDE * SIZE
      +	array3_size(COUNT, STRIDE, SIZE)
        , ...)
      )
      
      // Any remaining multi-factor products, first at least 3-factor products,
      // when they're not all constants...
      @@
      expression E1, E2, E3;
      constant C1, C2, C3;
      @@
      
      (
        kmalloc(C1 * C2 * C3, ...)
      |
        kmalloc(
      -	(E1) * E2 * E3
      +	array3_size(E1, E2, E3)
        , ...)
      |
        kmalloc(
      -	(E1) * (E2) * E3
      +	array3_size(E1, E2, E3)
        , ...)
      |
        kmalloc(
      -	(E1) * (E2) * (E3)
      +	array3_size(E1, E2, E3)
        , ...)
      |
        kmalloc(
      -	E1 * E2 * E3
      +	array3_size(E1, E2, E3)
        , ...)
      )
      
      // And then all remaining 2 factors products when they're not all constants,
      // keeping sizeof() as the second factor argument.
      @@
      expression THING, E1, E2;
      type TYPE;
      constant C1, C2, C3;
      @@
      
      (
        kmalloc(sizeof(THING) * C2, ...)
      |
        kmalloc(sizeof(TYPE) * C2, ...)
      |
        kmalloc(C1 * C2 * C3, ...)
      |
        kmalloc(C1 * C2, ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * (E2)
      +	E2, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(TYPE) * E2
      +	E2, sizeof(TYPE)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * (E2)
      +	E2, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	sizeof(THING) * E2
      +	E2, sizeof(THING)
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	(E1) * E2
      +	E1, E2
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	(E1) * (E2)
      +	E1, E2
        , ...)
      |
      - kmalloc
      + kmalloc_array
        (
      -	E1 * E2
      +	E1, E2
        , ...)
      )
      Signed-off-by: NKees Cook <keescook@chromium.org>
      6da2ec56
  21. 19 5月, 2018 1 次提交
  22. 17 5月, 2018 1 次提交
    • P
      sched: manipulate __QDISC_STATE_RUNNING in qdisc_run_* helpers · 32f7b44d
      Paolo Abeni 提交于
      Currently NOLOCK qdiscs pay a measurable overhead to atomically
      manipulate the __QDISC_STATE_RUNNING. Such bit is flipped twice per
      packet in the uncontended scenario with packet rate below the
      line rate: on packed dequeue and on the next, failing dequeue attempt.
      
      This changeset moves the bit manipulation into the qdisc_run_{begin,end}
      helpers, so that the bit is now flipped only once per packet, with
      measurable performance improvement in the uncontended scenario.
      
      This also allows simplifying the qdisc teardown code path - since
      qdisc_is_running() is now effective for each qdisc type - and avoid a
      possible race between qdisc_run() and dev_deactivate_many(), as now
      the some_qdisc_is_busy() can properly detect NOLOCK qdiscs being busy
      dequeuing packets.
      Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      32f7b44d
  23. 15 5月, 2018 1 次提交