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McKenney" Cc: Peter Zijlstra , Ingo Molnar , Ben Segall , Josh Don , linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Aniket Gattani Content-Type: text/plain; charset="UTF-8" Replace explicit lock/unlock and free calls with scoped guards and automatic cleanup constructs. Signed-off-by: Aniket Gattani --- kernel/sched/membarrier.c | 21 ++++----------------- 1 file changed, 4 insertions(+), 17 deletions(-) diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c index 3d88e900a17f..12b68a77630a 100644 --- a/kernel/sched/membarrier.c +++ b/kernel/sched/membarrier.c @@ -267,23 +267,19 @@ void membarrier_update_current_mm(struct mm_struct *next_mm) static int membarrier_global_expedited(void) { + cpumask_var_t __free(free_cpumask_var) tmpmask = CPUMASK_VAR_NULL; int cpu; - cpumask_var_t tmpmask; if (num_online_cpus() == 1) return 0; - /* - * Matches memory barriers after rq->curr modification in - * scheduler. - */ - smp_mb(); /* system call entry is not a mb. */ - if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL)) return -ENOMEM; + guard(mb)(); SERIALIZE_IPI(); - cpus_read_lock(); + guard(cpus_read_lock)(); + rcu_read_lock(); for_each_online_cpu(cpu) { struct task_struct *p; @@ -319,15 +315,6 @@ static int membarrier_global_expedited(void) smp_call_function_many(tmpmask, ipi_mb, NULL, 1); preempt_enable(); - free_cpumask_var(tmpmask); - cpus_read_unlock(); - - /* - * Memory barrier on the caller thread _after_ we finished - * waiting for the last IPI. Matches memory barriers before - * rq->curr modification in scheduler. - */ - smp_mb(); /* exit from system call is not a mb */ return 0; } -- 2.54.0.545.g6539524ca2-goog