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 46c142b69598..ca52041d5899 100644 --- a/kernel/sched/membarrier.c +++ b/kernel/sched/membarrier.c @@ -25,6 +25,8 @@ | MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED \ | MEMBARRIER_PRIVATE_EXPEDITED_SYNC_CORE_BITMASK) +static DEFINE_MUTEX(membarrier_ipi_mutex); + static void ipi_mb(void *info) { smp_mb(); /* IPIs should be serializing but paranoid. */ @@ -97,6 +99,7 @@ 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) { @@ -143,6 +146,8 @@ 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; } @@ -178,6 +183,7 @@ static int membarrier_private_expedited(int flags) 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) { @@ -212,6 +218,7 @@ static int membarrier_private_expedited(int flags) * rq->curr modification in scheduler. */ smp_mb(); /* exit from system call is not a mb */ + mutex_unlock(&membarrier_ipi_mutex); return 0; } @@ -253,6 +260,7 @@ 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) { @@ -269,6 +277,7 @@ static int sync_runqueues_membarrier_state(struct mm_struct *mm) free_cpumask_var(tmpmask); cpus_read_unlock(); + mutex_unlock(&membarrier_ipi_mutex); return 0; } |