When a caller enqueues a work item using schedule_delayed_work() the used wq is "system_wq" (per-cpu wq) while queue_delayed_work() uses WORK_CPU_UNBOUND (used when no target CPU is specified). The same applies to schedule_work() that is using system_wq and queue_work(), which again makes use of WORK_CPU_UNBOUND. This lack of consistency cannot be addressed without refactoring the API. Continue the effort to refactor workqueue APIs, which began with the introduction of new workqueues and a new alloc_workqueue() flag in: commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq") commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag") and switch smp_call_on_cpu() to use system_percpu_wq because system_wq is going away once the ongoing workqueue restructuring is done.
Unified · Split
| @@ -1185,7 +1185,7 @@ int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, bool phys) · 1184 unmodified lines | |||
| 1185 | if (cpu >= nr_cpu_ids || !cpu_online(cpu)) | 1185 | if (cpu >= nr_cpu_ids || !cpu_online(cpu)) |
| 1186 | return -ENXIO; | 1186 | return -ENXIO; |
| 1187 | 1187 | ||
| 1188 | queue_work_on(cpu, system_wq, &sscs.work); | 1188 | queue_work_on(cpu, system_percpu_wq, &sscs.work); |
| 1189 | wait_for_completion(&sscs.done); | 1189 | wait_for_completion(&sscs.done); |
| 1190 | destroy_work_on_stack(&sscs.work); | 1190 | destroy_work_on_stack(&sscs.work); |
| 1191 | 1191 | ||