From: Marco Crivellari Date: Mon, 10 Nov 2025 17:03:32 +0000 (+0100) Subject: smp: Use system_percpu_wq instead of system_wq X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7eb28030f641d5bc7682c98602f896304efd31d2;p=thirdparty%2Flinux.git smp: Use system_percpu_wq instead of system_wq 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. Suggested-by: Tejun Heo Signed-off-by: Marco Crivellari Signed-off-by: Thomas Gleixner Reviewed-by: Frederic Weisbecker Link: https://patch.msgid.link/20251110170332.319314-1-marco.crivellari@suse.com --- diff --git a/kernel/smp.c b/kernel/smp.c index 0fc4ff28ba79e..6c77848d91f30 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -1185,7 +1185,7 @@ int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, bool phys) if (cpu >= nr_cpu_ids || !cpu_online(cpu)) return -ENXIO; - queue_work_on(cpu, system_wq, &sscs.work); + queue_work_on(cpu, system_percpu_wq, &sscs.work); wait_for_completion(&sscs.done); destroy_work_on_stack(&sscs.work);