The patch titled Subject: lib/group_cpus: relax atomicity requirement in grp_spread_init_one() has been added to the -mm mm-nonmm-unstable branch. Its filename is lib-group_cpus-relax-atomicity-requirement-in-grp_spread_init_one.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-group_cpus-relax-atomicity-requirement-in-grp_spread_init_one.patch This patch will later appear in the mm-nonmm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Yury Norov <yury.norov@xxxxxxxxx> Subject: lib/group_cpus: relax atomicity requirement in grp_spread_init_one() Date: Thu, 7 Dec 2023 12:38:56 -0800 Because nmsk and irqmsk are stable, extra atomicity is not required. Link: https://lkml.kernel.org/r/20231207203900.859776-3-yury.norov@xxxxxxxxx Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx> Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Cc: Ming Lei <ming.lei@xxxxxxxxxx> Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/group_cpus.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) --- a/lib/group_cpus.c~lib-group_cpus-relax-atomicity-requirement-in-grp_spread_init_one +++ a/lib/group_cpus.c @@ -24,8 +24,8 @@ static void grp_spread_init_one(struct c if (cpu >= nr_cpu_ids) return; - cpumask_clear_cpu(cpu, nmsk); - cpumask_set_cpu(cpu, irqmsk); + __cpumask_clear_cpu(cpu, nmsk); + __cpumask_set_cpu(cpu, irqmsk); cpus_per_grp--; /* If the cpu has siblings, use them first */ @@ -34,9 +34,8 @@ static void grp_spread_init_one(struct c sibl = cpumask_next(sibl, siblmsk); if (sibl >= nr_cpu_ids) break; - if (!cpumask_test_and_clear_cpu(sibl, nmsk)) - continue; - cpumask_set_cpu(sibl, irqmsk); + __cpumask_clear_cpu(sibl, nmsk); + __cpumask_set_cpu(sibl, irqmsk); cpus_per_grp--; } } _ Patches currently in -mm which might be from yury.norov@xxxxxxxxx are cpumask-introduce-for_each_cpu_and_from.patch lib-group_cpus-relax-atomicity-requirement-in-grp_spread_init_one.patch lib-group_cpus-optimize-inner-loop-in-grp_spread_init_one.patch lib-group_cpus-optimize-outer-loop-in-grp_spread_init_one.patch lib-cgroup_cpusc-dont-zero-cpumasks-in-group_cpus_evenly-on-allocation.patch lib-group_cpusc-drop-unneeded-cpumask_empty-call-in-__group_cpus_evenly.patch