diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 12 | ||||
| -rw-r--r-- | Documentation/core-api/workqueue.rst | 32 |
2 files changed, 44 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 87bd0e3271b0..487d5da5355d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -6972,6 +6972,18 @@ it can be updated at runtime by writing to the corresponding sysfs file. + workqueue.cpu_intensive_thresh_us= + Per-cpu work items which run for longer than this + threshold are automatically considered CPU intensive + and excluded from concurrency management to prevent + them from noticeably delaying other per-cpu work + items. Default is 10000 (10ms). + + If CONFIG_WQ_CPU_INTENSIVE_REPORT is set, the kernel + will report the work functions which violate this + threshold repeatedly. They are likely good + candidates for using WQ_UNBOUND workqueues instead. + workqueue.disable_numa By default, all work items queued to unbound workqueues are affine to the NUMA nodes they're diff --git a/Documentation/core-api/workqueue.rst b/Documentation/core-api/workqueue.rst index 8ec4d6270b24..a4c9b9d1905f 100644 --- a/Documentation/core-api/workqueue.rst +++ b/Documentation/core-api/workqueue.rst @@ -348,6 +348,37 @@ Guidelines level of locality in wq operations and work item execution. +Monitoring +========== + +Use tools/workqueue/wq_monitor.py to monitor workqueue operations: :: + + $ tools/workqueue/wq_monitor.py events + total infl CPUtime CPUhog CMwake mayday rescued + events 18545 0 6.1 0 5 - - + events_highpri 8 0 0.0 0 0 - - + events_long 3 0 0.0 0 0 - - + events_unbound 38306 0 0.1 - - - - + events_freezable 0 0 0.0 0 0 - - + events_power_efficient 29598 0 0.2 0 0 - - + events_freezable_power_ 10 0 0.0 0 0 - - + sock_diag_events 0 0 0.0 0 0 - - + + total infl CPUtime CPUhog CMwake mayday rescued + events 18548 0 6.1 0 5 - - + events_highpri 8 0 0.0 0 0 - - + events_long 3 0 0.0 0 0 - - + events_unbound 38322 0 0.1 - - - - + events_freezable 0 0 0.0 0 0 - - + events_power_efficient 29603 0 0.2 0 0 - - + events_freezable_power_ 10 0 0.0 0 0 - - + sock_diag_events 0 0 0.0 0 0 - - + + ... + +See the command's help message for more info. + + Debugging ========= @@ -387,6 +418,7 @@ the stack trace of the offending worker thread. :: The work item's function should be trivially visible in the stack trace. + Non-reentrance Conditions ========================= |