From: Marco Crivellari Date: Fri, 5 Sep 2025 09:05:32 +0000 (+0200) Subject: padata: replace use of system_unbound_wq with system_dfl_wq X-Git-Tag: v6.18-rc1~84^2~18 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b6d02e0e41aa87aaa46b9b995e71a585284c5d27;p=thirdparty%2Fkernel%2Flinux.git padata: replace use of system_unbound_wq with system_dfl_wq 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: Herbert Xu --- diff --git a/kernel/padata.c b/kernel/padata.c index 833740d75483..d7cc95367209 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -490,9 +490,9 @@ void __init padata_do_multithreaded(struct padata_mt_job *job) do { nid = next_node_in(old_node, node_states[N_CPU]); } while (!atomic_try_cmpxchg(&last_used_nid, &old_node, nid)); - queue_work_node(nid, system_unbound_wq, &pw->pw_work); + queue_work_node(nid, system_dfl_wq, &pw->pw_work); } else { - queue_work(system_unbound_wq, &pw->pw_work); + queue_work(system_dfl_wq, &pw->pw_work); } /* Use the current thread, which saves starting a workqueue worker. */