[PATCH 02/31] workqueue: make workqueue_lock irq-safe

Tejun Heo
2013-03-02T03:24:53Z

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>
---
kernel/workqueue.c | 44 ++++++++++++++++++++++----------------------
1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index a533e77..61f78ef 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -2717,10 +2717,10 @@ 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);

@@ -2742,10 +2742,10 @@ 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);

@@ -3235,7 +3235,7 @@ 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)
@@ -3243,7 +3243,7 @@ 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:
@@ -3287,9 +3287,9 @@ 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);
@@ -3338,7 +3338,7 @@ 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;

@@ -3346,16 +3346,16 @@ 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);

@@ -3602,7 +3602,7 @@ 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;
@@ -3612,7 +3612,7 @@ 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;
@@ -3625,11 +3625,11 @@ 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);
}

/**
@@ -3650,7 +3650,7 @@ 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);

@@ -3674,7 +3674,7 @@ bool freeze_workqueues_busy(void)
}
}
out_unlock:
- spin_unlock(&workqueue_lock);
+ spin_unlock_irq(&workqueue_lock);
return busy;
}

@@ -3691,7 +3691,7 @@ void thaw_workqueues(void)
{
unsigned int cpu;

- spin_lock(&workqueue_lock);
+ spin_lock_irq(&workqueue_lock);

if (!workqueue_freezing)
goto out_unlock;
@@ -3701,7 +3701,7 @@ 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;
@@ -3719,13 +3719,13 @@ 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 */

--
1.8.1.2