From 5a629ecbcdffacfb04fc4eb0098c0688f38c8b9d Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 5 Nov 2025 12:03:08 -1000 Subject: [PATCH] sched_ext: Mark racy bitfields to prevent adding fields that can't tolerate races The warned bitfields in struct scx_sched are updated racily from concurrent CPUs causing RMW races, which is fine for these boolean warning flags. Add a comment marking this area to prevent future fields that can't tolerate racy updates from being added here. Signed-off-by: Tejun Heo --- kernel/sched/ext_internal.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/sched/ext_internal.h b/kernel/sched/ext_internal.h index fb161fc35328c..dd6f25fb6159c 100644 --- a/kernel/sched/ext_internal.h +++ b/kernel/sched/ext_internal.h @@ -895,6 +895,10 @@ struct scx_sched { struct scx_dispatch_q **global_dsqs; struct scx_sched_pcpu __percpu *pcpu; + /* + * Updates to the following warned bitfields can race causing RMW issues + * but it doesn't really matter. + */ bool warned_zero_slice:1; bool warned_deprecated_rq:1; -- 2.47.3