diff options
| -rw-r--r-- | kernel/workqueue.c | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 11723c5..4fef952 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -570,11 +570,19 @@ static void set_work_cwq(struct work_struct *work, static void set_work_cpu_and_clear_pending(struct work_struct *work, unsigned int cpu) { + /* + * The following wmb is paired with the implied mb in + * test_and_set_bit(PENDING) and ensures all updates to @work made + * here are visible to and precede any updates by the next PENDING + * owner. + */ + smp_wmb(); set_work_data(work, (unsigned long)cpu << WORK_OFFQ_CPU_SHIFT, 0); } static void clear_work_data(struct work_struct *work) { + smp_wmb(); /* see set_work_cpu_and_clear_pending() */ set_work_data(work, WORK_STRUCT_NO_CPU, 0); } @@ -2182,14 +2190,11 @@ __acquires(&gcwq->lock) wake_up_worker(pool); /* - * Record the last CPU and clear PENDING. The following wmb is - * paired with the implied mb in test_and_set_bit(PENDING) and - * ensures all updates to @work made here are visible to and - * precede any updates by the next PENDING owner. Also, clear - * PENDING inside @gcwq->lock so that PENDING and queued state - * changes happen together while IRQ is disabled. + * Record the last CPU and clear PENDING which should be the last + * update to @work. Also, do this inside @gcwq->lock so that + * PENDING and queued state changes happen together while IRQ is + * disabled. */ - smp_wmb(); set_work_cpu_and_clear_pending(work, gcwq->cpu); spin_unlock_irq(&gcwq->lock); |
