workqueue: make workqueue_lock irq-safe

workqueue_lock will be used to synchronize areas which require
irq-safety and there isn't much benefit in keeping it not irq-safe.
Make it irq-safe.

This patch doesn't introduce any visible behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index c6e1bdb..c585d0e 100644 (file)
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -2715,10 +2715,10 @@ void drain_workqueue(struct workqueue_struct *wq)
         * hotter than drain_workqueue() and already looks at @wq->flags.
         * Use WQ_DRAINING so that queue doesn't have to check nr_drainers.
         */
-       spin_lock(&workqueue_lock);
+       spin_lock_irq(&workqueue_lock);
        if (!wq->nr_drainers++)
                wq->flags |= WQ_DRAINING;
-       spin_unlock(&workqueue_lock);
+       spin_unlock_irq(&workqueue_lock);
 reflush:
        flush_workqueue(wq);
 
@@ -2740,10 +2740,10 @@ reflush:
                goto reflush;
        }
 
-       spin_lock(&workqueue_lock);
+       spin_lock_irq(&workqueue_lock);
        if (!--wq->nr_drainers)
                wq->flags &= ~WQ_DRAINING;
-       spin_unlock(&workqueue_lock);
+       spin_unlock_irq(&workqueue_lock);
 }
 EXPORT_SYMBOL_GPL(drain_workqueue);
 
@@ -3233,7 +3233,7 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
         * list.  Grab it, set max_active accordingly and add the new
         * workqueue to workqueues list.
         */
-       spin_lock(&workqueue_lock);
+       spin_lock_irq(&workqueue_lock);
 
        if (workqueue_freezing && wq->flags & WQ_FREEZABLE)
                for_each_pwq_cpu(cpu, wq)
@@ -3241,7 +3241,7 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
 
        list_add(&wq->list, &workqueues);
 
-       spin_unlock(&workqueue_lock);
+       spin_unlock_irq(&workqueue_lock);
 
        return wq;
 err:
@@ -3285,9 +3285,9 @@ void destroy_workqueue(struct workqueue_struct *wq)
         * wq list is used to freeze wq, remove from list after
         * flushing is complete in case freeze races us.
         */
-       spin_lock(&workqueue_lock);
+       spin_lock_irq(&workqueue_lock);
        list_del(&wq->list);
-       spin_unlock(&workqueue_lock);
+       spin_unlock_irq(&workqueue_lock);
 
        if (wq->flags & WQ_RESCUER) {
                kthread_stop(wq->rescuer->task);
@@ -3336,7 +3336,7 @@ void workqueue_set_max_active(struct workqueue_struct *wq, int max_active)
 
        max_active = wq_clamp_max_active(max_active, wq->flags, wq->name);
 
-       spin_lock(&workqueue_lock);
+       spin_lock_irq(&workqueue_lock);
 
        wq->saved_max_active = max_active;
 
@@ -3344,16 +3344,16 @@ void workqueue_set_max_active(struct workqueue_struct *wq, int max_active)
                struct pool_workqueue *pwq = get_pwq(cpu, wq);
                struct worker_pool *pool = pwq->pool;
 
-               spin_lock_irq(&pool->lock);
+               spin_lock(&pool->lock);
 
                if (!(wq->flags & WQ_FREEZABLE) ||
                    !(pool->flags & POOL_FREEZING))
                        pwq_set_max_active(pwq, max_active);
 
-               spin_unlock_irq(&pool->lock);
+               spin_unlock(&pool->lock);
        }
 
-       spin_unlock(&workqueue_lock);
+       spin_unlock_irq(&workqueue_lock);
 }
 EXPORT_SYMBOL_GPL(workqueue_set_max_active);
 
@@ -3599,7 +3599,7 @@ void freeze_workqueues_begin(void)
 {
        unsigned int cpu;
 
-       spin_lock(&workqueue_lock);
+       spin_lock_irq(&workqueue_lock);
 
        WARN_ON_ONCE(workqueue_freezing);
        workqueue_freezing = true;
@@ -3609,7 +3609,7 @@ void freeze_workqueues_begin(void)
                struct workqueue_struct *wq;
 
                for_each_std_worker_pool(pool, cpu) {
-                       spin_lock_irq(&pool->lock);
+                       spin_lock(&pool->lock);
 
                        WARN_ON_ONCE(pool->flags & POOL_FREEZING);
                        pool->flags |= POOL_FREEZING;
@@ -3622,11 +3622,11 @@ void freeze_workqueues_begin(void)
                                        pwq->max_active = 0;
                        }
 
-                       spin_unlock_irq(&pool->lock);
+                       spin_unlock(&pool->lock);
                }
        }
 
-       spin_unlock(&workqueue_lock);
+       spin_unlock_irq(&workqueue_lock);
 }
 
 /**
@@ -3647,7 +3647,7 @@ bool freeze_workqueues_busy(void)
        unsigned int cpu;
        bool busy = false;
 
-       spin_lock(&workqueue_lock);
+       spin_lock_irq(&workqueue_lock);
 
        WARN_ON_ONCE(!workqueue_freezing);
 
@@ -3671,7 +3671,7 @@ bool freeze_workqueues_busy(void)
                }
        }
 out_unlock:
-       spin_unlock(&workqueue_lock);
+       spin_unlock_irq(&workqueue_lock);
        return busy;
 }
 
@@ -3688,7 +3688,7 @@ void thaw_workqueues(void)
 {
        unsigned int cpu;
 
-       spin_lock(&workqueue_lock);
+       spin_lock_irq(&workqueue_lock);
 
        if (!workqueue_freezing)
                goto out_unlock;
@@ -3698,7 +3698,7 @@ void thaw_workqueues(void)
                struct workqueue_struct *wq;
 
                for_each_std_worker_pool(pool, cpu) {
-                       spin_lock_irq(&pool->lock);
+                       spin_lock(&pool->lock);
 
                        WARN_ON_ONCE(!(pool->flags & POOL_FREEZING));
                        pool->flags &= ~POOL_FREEZING;
@@ -3716,13 +3716,13 @@ void thaw_workqueues(void)
 
                        wake_up_worker(pool);
 
-                       spin_unlock_irq(&pool->lock);
+                       spin_unlock(&pool->lock);
                }
        }
 
        workqueue_freezing = false;
 out_unlock:
-       spin_unlock(&workqueue_lock);
+       spin_unlock_irq(&workqueue_lock);
 }
 #endif /* CONFIG_FREEZER */