diff options
| -rw-r--r-- | kernel/sched/core.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index f5e37c233b01..2ea77e72f7c6 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2684,6 +2684,7 @@ void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx cpumask_copy(&p->cpus_mask, ctx->new_mask); p->nr_cpus_allowed = cpumask_weight(ctx->new_mask); + mm_update_cpus_allowed(p->mm, ctx->new_mask); /* * Swap in a new user_cpus_ptr if SCA_USER flag set @@ -2730,7 +2731,6 @@ __do_set_cpus_allowed(struct task_struct *p, struct affinity_context *ctx) put_prev_task(rq, p); p->sched_class->set_cpus_allowed(p, ctx); - mm_update_cpus_allowed(p->mm, ctx->new_mask); if (queued) enqueue_task(rq, p, ENQUEUE_RESTORE | ENQUEUE_NOCLOCK); @@ -10376,12 +10376,17 @@ void call_trace_sched_update_nr_running(struct rq *rq, int count) */ static inline void mm_update_cpus_allowed(struct mm_struct *mm, const struct cpumask *affmsk) { - struct cpumask *mm_allowed = mm_cpus_allowed(mm); + struct cpumask *mm_allowed; if (!mm) return; - /* The mm_cpus_allowed is the union of each thread allowed CPUs masks. */ + + /* + * mm::mm_cid::mm_cpus_allowed is the superset of each threads + * allowed CPUs mask which means it can only grow. + */ guard(raw_spinlock)(&mm->mm_cid.lock); + mm_allowed = mm_cpus_allowed(mm); cpumask_or(mm_allowed, mm_allowed, affmsk); WRITE_ONCE(mm->mm_cid.nr_cpus_allowed, cpumask_weight(mm_allowed)); } |