1. 20 5月, 2018 3 次提交
  2. 11 5月, 2018 1 次提交
  3. 01 4月, 2018 1 次提交
  4. 17 1月, 2018 3 次提交
  5. 18 10月, 2017 1 次提交
    • I
      mlxsw: core: Fix possible deadlock · d965465b
      Ido Schimmel 提交于
      When an EMAD is transmitted, a timeout work item is scheduled with a
      delay of 200ms, so that another EMAD will be retried until a maximum of
      five retries.
      
      In certain situations, it's possible for the function waiting on the
      EMAD to be associated with a work item that is queued on the same
      workqueue (`mlxsw_core`) as the timeout work item. This results in
      flushing a work item on the same workqueue.
      
      According to commit e159489b ("workqueue: relax lockdep annotation
      on flush_work()") the above may lead to a deadlock in case the workqueue
      has only one worker active or if the system in under memory pressure and
      the rescue worker is in use. The latter explains the very rare and
      random nature of the lockdep splats we have been seeing:
      
      [   52.730240] ============================================
      [   52.736179] WARNING: possible recursive locking detected
      [   52.742119] 4.14.0-rc3jiri+ #4 Not tainted
      [   52.746697] --------------------------------------------
      [   52.752635] kworker/1:3/599 is trying to acquire lock:
      [   52.758378]  (mlxsw_core_driver_name){+.+.}, at: [<ffffffff811c4fa4>] flush_work+0x3a4/0x5e0
      [   52.767837]
                     but task is already holding lock:
      [   52.774360]  (mlxsw_core_driver_name){+.+.}, at: [<ffffffff811c65c4>] process_one_work+0x7d4/0x12f0
      [   52.784495]
                     other info that might help us debug this:
      [   52.791794]  Possible unsafe locking scenario:
      [   52.798413]        CPU0
      [   52.801144]        ----
      [   52.803875]   lock(mlxsw_core_driver_name);
      [   52.808556]   lock(mlxsw_core_driver_name);
      [   52.813236]
                      *** DEADLOCK ***
      [   52.819857]  May be due to missing lock nesting notation
      [   52.827450] 3 locks held by kworker/1:3/599:
      [   52.832221]  #0:  (mlxsw_core_driver_name){+.+.}, at: [<ffffffff811c65c4>] process_one_work+0x7d4/0x12f0
      [   52.842846]  #1:  ((&(&bridge->fdb_notify.dw)->work)){+.+.}, at: [<ffffffff811c65c4>] process_one_work+0x7d4/0x12f0
      [   52.854537]  #2:  (rtnl_mutex){+.+.}, at: [<ffffffff822ad8e7>] rtnl_lock+0x17/0x20
      [   52.863021]
                     stack backtrace:
      [   52.867890] CPU: 1 PID: 599 Comm: kworker/1:3 Not tainted 4.14.0-rc3jiri+ #4
      [   52.875773] Hardware name: Mellanox Technologies Ltd. "MSN2100-CB2F"/"SA001017", BIOS 5.6.5 06/07/2016
      [   52.886267] Workqueue: mlxsw_core mlxsw_sp_fdb_notify_work [mlxsw_spectrum]
      [   52.894060] Call Trace:
      [   52.909122]  __lock_acquire+0xf6f/0x2a10
      [   53.025412]  lock_acquire+0x158/0x440
      [   53.047557]  flush_work+0x3c4/0x5e0
      [   53.087571]  __cancel_work_timer+0x3ca/0x5e0
      [   53.177051]  cancel_delayed_work_sync+0x13/0x20
      [   53.182142]  mlxsw_reg_trans_bulk_wait+0x12d/0x7a0 [mlxsw_core]
      [   53.194571]  mlxsw_core_reg_access+0x586/0x990 [mlxsw_core]
      [   53.225365]  mlxsw_reg_query+0x10/0x20 [mlxsw_core]
      [   53.230882]  mlxsw_sp_fdb_notify_work+0x2a3/0x9d0 [mlxsw_spectrum]
      [   53.237801]  process_one_work+0x8f1/0x12f0
      [   53.321804]  worker_thread+0x1fd/0x10c0
      [   53.435158]  kthread+0x28e/0x370
      [   53.448703]  ret_from_fork+0x2a/0x40
      [   53.453017] mlxsw_spectrum 0000:01:00.0: EMAD retries (2/5) (tid=bf4549b100000774)
      [   53.453119] mlxsw_spectrum 0000:01:00.0: EMAD retries (5/5) (tid=bf4549b100000770)
      [   53.453132] mlxsw_spectrum 0000:01:00.0: EMAD reg access failed (tid=bf4549b100000770,reg_id=200b(sfn),type=query,status=0(operation performed))
      [   53.453143] mlxsw_spectrum 0000:01:00.0: Failed to get FDB notifications
      
      Fix this by creating another workqueue for EMAD timeouts, thereby
      preventing the situation of a work item trying to flush a work item
      queued on the same workqueue.
      
      Fixes: caf7297e ("mlxsw: core: Introduce support for asynchronous EMAD register access")
      Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
      Reported-by: NJiri Pirko <jiri@mellanox.com>
      Signed-off-by: NJiri Pirko <jiri@mellanox.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d965465b
  6. 03 8月, 2017 1 次提交
  7. 25 3月, 2017 1 次提交
  8. 24 3月, 2017 1 次提交
  9. 07 2月, 2017 1 次提交
  10. 04 12月, 2016 1 次提交
    • I
      mlxsw: core: Create an ordered workqueue for FIB offload · a3832b31
      Ido Schimmel 提交于
      We're going to start processing FIB entries addition / deletion events
      in deferred work. These work items must be processed in the order they
      were submitted or otherwise we can have differences between the kernel's
      FIB table and the device's.
      
      Solve this by creating an ordered workqueue to which these work items
      will be submitted to. Note that we can't simply convert the current
      workqueue to be ordered, as EMADs re-transmissions are also processed in
      deferred work.
      
      Later on, we can migrate other work items to this workqueue, such as FDB
      notification processing and nexthop resolution, since they all take the
      same lock anyway.
      Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
      Signed-off-by: NJiri Pirko <jiri@mellanox.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a3832b31
  11. 30 11月, 2016 2 次提交
  12. 26 11月, 2016 3 次提交
  13. 22 11月, 2016 1 次提交
  14. 17 11月, 2016 2 次提交
  15. 31 10月, 2016 3 次提交
  16. 29 10月, 2016 1 次提交
  17. 24 10月, 2016 1 次提交
  18. 21 9月, 2016 1 次提交
  19. 25 7月, 2016 1 次提交
  20. 13 7月, 2016 1 次提交
  21. 10 6月, 2016 1 次提交
    • B
      mlxsw: core: Remove deprecated create_workqueue · 3d5479e9
      Bhaktipriya Shridhar 提交于
      alloc_workqueue replaces deprecated create_workqueue().
      
      A dedicated workqueue has been used since the workqueue
      mlxsw_wq is used for FDB notif. processing with workitems that are
      involved in normal device operation && because it's a network device
      which can be depended upon during memory reclaim.
      
      Workitems &trans->timeout_dw and &mlxsw_sp->fdb_notify.dw,
      map to mlxsw_sp_fdb_notify_work (processes FDB notifications from the
      underlying device and resolves the netdev to which the entry points to
      and notifies the bridge using the switchdev notifier) and
      mlxsw_emad_trans_timeout_work (provides async EMAD register access)
      respectively. They require forward progress under memory pressure and
      hence, WQ_MEM_RECLAIM has been set.
      
      Since there are only a fixed number of work items, explicit concurrency
      limit is unnecessary here.
      Signed-off-by: NBhaktipriya Shridhar <bhaktipriya96@gmail.com>
      Tested-by: NIdo Schimmel <idosch@mellanox.com>
      Acked-by: NJiri Pirko <jiri@mellanox.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3d5479e9
  22. 15 4月, 2016 4 次提交
  23. 09 4月, 2016 3 次提交
  24. 02 3月, 2016 2 次提交