as-iosched: fix inconsistent ioc->lock context
authorJens Axboe <jens.axboe@oracle.com>
Fri, 1 Feb 2008 08:44:28 +0000 (09:44 +0100)
committerJens Axboe <jens.axboe@oracle.com>
Fri, 1 Feb 2008 08:44:28 +0000 (09:44 +0100)
Since it's acquired from irq context, all locking must be of the
irq safe variant. Most are already inside the queue lock (which
already disables interrupts), but the io scheduler rmmod path
always has irqs enabled and the put_io_context() path may legally
be called with irqs enabled (even if it isn't usually). So fixup
those two.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
block/as-iosched.c

index 96036846a0017505691060d62734afc0dcad9529..612d640963006a45a677571b93aa2e182a8e5d09 100644 (file)
@@ -170,11 +170,11 @@ static void free_as_io_context(struct as_io_context *aic)
 
 static void as_trim(struct io_context *ioc)
 {
-       spin_lock(&ioc->lock);
+       spin_lock_irq(&ioc->lock);
        if (ioc->aic)
                free_as_io_context(ioc->aic);
        ioc->aic = NULL;
-       spin_unlock(&ioc->lock);
+       spin_unlock_irq(&ioc->lock);
 }
 
 /* Called when the task exits */
@@ -235,10 +235,12 @@ static void as_put_io_context(struct request *rq)
        aic = RQ_IOC(rq)->aic;
 
        if (rq_is_sync(rq) && aic) {
-               spin_lock(&aic->lock);
+               unsigned long flags;
+
+               spin_lock_irqsave(&aic->lock, flags);
                set_bit(AS_TASK_IORUNNING, &aic->state);
                aic->last_end_request = jiffies;
-               spin_unlock(&aic->lock);
+               spin_unlock_irqrestore(&aic->lock, flags);
        }
 
        put_io_context(RQ_IOC(rq));