From eed8c02e680c04cd737e0a9cef74e68d8eb0cefa Mon Sep 17 00:00:00 2001 From: Lukas Czerner Date: Fri, 30 Nov 2012 11:42:40 +0100 Subject: wait: add wait_event_lock_irq() interface New wait_event{_interruptible}_lock_irq{_cmd} macros added. This commit moves the private wait_event_lock_irq() macro from MD to regular wait includes, introduces new macro wait_event_lock_irq_cmd() instead of using the old method with omitting cmd parameter which is ugly and makes a use of new macros in the MD. It also introduces the _interruptible_ variant. The use of new interface is when one have a special lock to protect data structures used in the condition, or one also needs to invoke "cmd" before putting it to sleep. All new macros are expected to be called with the lock taken. The lock is released before sleep and is reacquired afterwards. We will leave the macro with the lock held. Note to DM: IMO this should also fix theoretical race on waitqueue while using simultaneously wait_event_lock_irq() and wait_event() because of lack of locking around current state setting and wait queue removal. Signed-off-by: Lukas Czerner Cc: Neil Brown Cc: David Howells Cc: Ingo Molnar Cc: Peter Zijlstra Signed-off-by: Jens Axboe --- drivers/md/raid10.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) (limited to 'drivers/md/raid10.c') diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 906ccbd0f7dc..9a08f621b27d 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -952,7 +952,7 @@ static void raise_barrier(struct r10conf *conf, int force) /* Wait until no block IO is waiting (unless 'force') */ wait_event_lock_irq(conf->wait_barrier, force || !conf->nr_waiting, - conf->resync_lock, ); + conf->resync_lock); /* block any new IO from starting */ conf->barrier++; @@ -960,7 +960,7 @@ static void raise_barrier(struct r10conf *conf, int force) /* Now wait for all pending IO to complete */ wait_event_lock_irq(conf->wait_barrier, !conf->nr_pending && conf->barrier < RESYNC_DEPTH, - conf->resync_lock, ); + conf->resync_lock); spin_unlock_irq(&conf->resync_lock); } @@ -993,8 +993,7 @@ static void wait_barrier(struct r10conf *conf) (conf->nr_pending && current->bio_list && !bio_list_empty(current->bio_list)), - conf->resync_lock, - ); + conf->resync_lock); conf->nr_waiting--; } conf->nr_pending++; @@ -1027,10 +1026,10 @@ static void freeze_array(struct r10conf *conf) spin_lock_irq(&conf->resync_lock); conf->barrier++; conf->nr_waiting++; - wait_event_lock_irq(conf->wait_barrier, - conf->nr_pending == conf->nr_queued+1, - conf->resync_lock, - flush_pending_writes(conf)); + wait_event_lock_irq_cmd(conf->wait_barrier, + conf->nr_pending == conf->nr_queued+1, + conf->resync_lock, + flush_pending_writes(conf)); spin_unlock_irq(&conf->resync_lock); } -- cgit v1.2.1