diff options
Diffstat (limited to 'kernel/sched/membarrier.c')
| -rw-r--r-- | kernel/sched/membarrier.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c index cc7cd512e..1b7c3bdba 100644 --- a/kernel/sched/membarrier.c +++ b/kernel/sched/membarrier.c @@ -34,6 +34,8 @@ | MEMBARRIER_PRIVATE_EXPEDITED_SYNC_CORE_BITMASK \ | MEMBARRIER_PRIVATE_EXPEDITED_RSEQ_BITMASK) +static DEFINE_MUTEX(membarrier_ipi_mutex); + static void ipi_mb(void *info) { smp_mb(); /* IPIs should be serializing but paranoid. */ @@ -119,6 +121,7 @@ static int membarrier_global_expedited(void) if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL)) return -ENOMEM; + mutex_lock(&membarrier_ipi_mutex); cpus_read_lock(); rcu_read_lock(); for_each_online_cpu(cpu) { @@ -165,6 +168,8 @@ static int membarrier_global_expedited(void) * rq->curr modification in scheduler. */ smp_mb(); /* exit from system call is not a mb */ + mutex_unlock(&membarrier_ipi_mutex); + return 0; } @@ -208,6 +213,7 @@ static int membarrier_private_expedited(int flags, int cpu_id) if (cpu_id < 0 && !zalloc_cpumask_var(&tmpmask, GFP_KERNEL)) return -ENOMEM; + mutex_lock(&membarrier_ipi_mutex); cpus_read_lock(); if (cpu_id >= 0) { @@ -280,6 +286,7 @@ out: * rq->curr modification in scheduler. */ smp_mb(); /* exit from system call is not a mb */ + mutex_unlock(&membarrier_ipi_mutex); return 0; } @@ -321,6 +328,7 @@ static int sync_runqueues_membarrier_state(struct mm_struct *mm) * between threads which are users of @mm has its membarrier state * updated. */ + mutex_lock(&membarrier_ipi_mutex); cpus_read_lock(); rcu_read_lock(); for_each_online_cpu(cpu) { @@ -337,6 +345,7 @@ static int sync_runqueues_membarrier_state(struct mm_struct *mm) free_cpumask_var(tmpmask); cpus_read_unlock(); + mutex_unlock(&membarrier_ipi_mutex); return 0; } |