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.
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| @@ -2932,7 +2932,7 @@ static void idle_worker_timeout(struct timer_list *t) · 2931 unmodified lines | |||
| 2932 | raw_spin_unlock_irq(&pool->lock); | 2932 | raw_spin_unlock_irq(&pool->lock); |
| 2933 | 2933 | ||
| 2934 | if (do_cull) | 2934 | if (do_cull) |
| 2935 | queue_work(system_unbound_wq, &pool->idle_cull_work); | 2935 | queue_work(system_dfl_wq, &pool->idle_cull_work); |
| 2936 | } | 2936 | } |
| 2937 | 2937 | ||
| 2938 | /** | 2938 | /** |