kernel/linux.git/include/linux/workqueue.h, branch v7.0-rc7

cpuset: Propagate cpuset isolation update to workqueue through housekeeping

2026-02-03T14:23:34+00:00

Until now, cpuset would propagate isolated partition changes to workqueues so that unbound workers get properly reaffined. Since housekeeping now centralizes, synchronize and propagates isolation cpumask changes, perform the work from that subsystem for consolidation and consistency purposes. For simplification purpose, the target function is adapted to take the new housekeeping mask instead of the isolated mask. Suggested-by: Tejun Heo Signed-off-by: Frederic Weisbecker Reviewed-by: Waiman Long Acked-by: Tejun Heo Cc: "Michal Koutný" Cc: Ingo Molnar Cc: Johannes Weiner Cc: Lai Jiangshan Cc: Marco Crivellari Cc: Michal Hocko Cc: Peter Zijlstra Cc: Tejun Heo Cc: Thomas Gleixner Cc: Vlastimil Babka Cc: Waiman Long Cc: cgroups@vger.kernel.org

workqueue: fix texinfodocs warning for WQ_* flags reference

2025-09-22T15:37:20+00:00

Sphinx emitted a warning during make texinfodocs: WARNING: Inline literal start-string without end-string. This was caused by the trailing '*' in "%WQ_*" being parsed as reStructuredText markup in the kernel-doc comment. Escape the '*' in the comment so that Sphinx treats it as a literal character, resolving the warning. Signed-off-by: Kriish Sharma Signed-off-by: Tejun Heo

workqueue: WQ_PERCPU added to alloc_workqueue users

2025-09-16T20:33:53+00:00

Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistentcy cannot be addressed without refactoring the API. alloc_workqueue() treats all queues as per-CPU by default, while unbound workqueues must opt-in via WQ_UNBOUND. This default is suboptimal: most workloads benefit from unbound queues, allowing the scheduler to place worker threads where they’re needed and reducing noise when CPUs are isolated. This patch adds a new WQ_PERCPU flag to explicitly request the use of the per-CPU behavior. Both flags coexist for one release cycle to allow callers to transition their calls. Once migration is complete, WQ_UNBOUND can be removed and unbound will become the implicit default. With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND), any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND must now use WQ_PERCPU. All existing users have been updated accordingly. Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Signed-off-by: Tejun Heo

workqueue: replace use of system_wq with system_percpu_wq

2025-09-05T17:20:00+00:00

Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistentcy cannot be addressed without refactoring the API. system_wq is a per-CPU worqueue, yet nothing in its name tells about that CPU affinity constraint, which is very often not required by users. Make it clear by adding a system_percpu_wq. queue_work() / queue_delayed_work() mod_delayed_work() will now use the new per-cpu wq: whether the user still stick on the old name a warn will be printed along a wq redirect to the new one. This patch add the new system_percpu_wq except for mm, fs and net subsystem, whom are handled in separated patches. The old wq will be kept for a few release cylces. Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Signed-off-by: Tejun Heo

workqueue: replace use of system_unbound_wq with system_dfl_wq

2025-09-05T17:19:09+00:00

Currently if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistentcy cannot be addressed without refactoring the API. system_unbound_wq should be the default workqueue so as not to enforce locality constraints for random work whenever it's not required. Adding system_dfl_wq to encourage its use when unbound work should be used. queue_work() / queue_delayed_work() / mod_delayed_work() will now use the new unbound wq: whether the user still use the old wq a warn will be printed along with a wq redirect to the new one. The old system_unbound_wq will be kept for a few release cycles. Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Signed-off-by: Tejun Heo

workqueue: Remove unused work_on_cpu_safe

2025-06-23T18:07:06+00:00

The last use of the work_on_cpu_safe() macro was removed recently by commit 9cda46babdfe ("crypto: n2 - remove Niagara2 SPU driver") Remove it, and the work_on_cpu_safe_key() function it calls. Signed-off-by: Dr. David Alan Gilbert Signed-off-by: Tejun Heo

Merge branch 'WQ_PERCPU' into for-6.17

2025-06-17T18:52:50+00:00

workqueue: Add new WQ_PERCPU flag

2025-06-17T18:52:09+00:00

workqueue: Add system_percpu_wq and system_dfl_wq

2025-06-17T18:51:34+00:00

Currently, if a user enqueue a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to schedule_work() that is using system_wq and queue_work(), that makes use again of WORK_CPU_UNBOUND. This lack of consistentcy cannot be addressed without refactoring the API. system_wq is a per-CPU worqueue, yet nothing in its name tells about that CPU affinity constraint, which is very often not required by users. Make it clear by adding a system_percpu_wq. system_unbound_wq should be the default workqueue so as not to enforce locality constraints for random work whenever it's not required. Adding system_dfl_wq to encourage its use when unbound work should be used. Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Signed-off-by: Tejun Heo

workqueue: Basic memory allocation profiling support

2025-06-16T18:01:45+00:00

Hook alloc_workqueue and alloc_workqueue_attrs() so that they're accounted to the callsite. Since we're doing allocations on behalf of another subsystem, this helps when using memory allocation profiling to check for leaks. Cc: Tejun Heo Cc: Lai Jiangshan Signed-off-by: Kent Overstreet Signed-off-by: Tejun Heo