workqueue: invert the order between pool->lock and wq_mayday_lock
Currently, pool->lock nests inside pool->lock. There's no inherent
reason for this order. The only place where the two locks are held
together is pool_mayday_timeout() and it just got decided that way.
This nesting order turns out to complicate things with the planned
rescuer_thread() update. Let's invert them. This doesn't cause any
behavior differences.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Dongsu Park <dongsu.park@profitbricks.com>
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 5fcd817..3992cf6 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1804,8 +1804,8 @@
struct worker_pool *pool = (void *)__pool;
struct work_struct *work;
- spin_lock_irq(&wq_mayday_lock); /* for wq->maydays */
- spin_lock(&pool->lock);
+ spin_lock_irq(&pool->lock);
+ spin_lock(&wq_mayday_lock); /* for wq->maydays */
if (need_to_create_worker(pool)) {
/*
@@ -1818,8 +1818,8 @@
send_mayday(work);
}
- spin_unlock(&pool->lock);
- spin_unlock_irq(&wq_mayday_lock);
+ spin_unlock(&wq_mayday_lock);
+ spin_unlock_irq(&pool->lock);
mod_timer(&pool->mayday_timer, jiffies + MAYDAY_INTERVAL);
}