From 2bded7bd7e8b12a913b0b58167a48220560e1514 Mon Sep 17 00:00:00 2001 From: Kiyoshi Ueda Date: Sat, 6 Mar 2010 02:32:13 +0000 Subject: dm mpath: wait for pg_init completion when suspending When suspending the device we must wait for all I/O to complete, but pg-init may be still in progress even after flushing the workqueue for kmpath_handlerd in multipath_postsuspend. This patch waits for pg-init completion correctly in multipath_postsuspend(). Signed-off-by: Kiyoshi Ueda Signed-off-by: Jun'ichi Nomura Signed-off-by: Alasdair G Kergon --- drivers/md/dm-mpath.c | 38 +++++++++++++++++++++++++++++++++++--- 1 file changed, 35 insertions(+), 3 deletions(-) (limited to 'drivers/md/dm-mpath.c') diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index ae187e5d7d5..030bc2a053e 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -69,6 +69,7 @@ struct multipath { struct list_head priority_groups; unsigned pg_init_required; /* pg_init needs calling? */ unsigned pg_init_in_progress; /* Only one pg_init allowed at once */ + wait_queue_head_t pg_init_wait; /* Wait for pg_init completion */ unsigned nr_valid_paths; /* Total number of usable paths */ struct pgpath *current_pgpath; @@ -200,6 +201,7 @@ static struct multipath *alloc_multipath(struct dm_target *ti) m->queue_io = 1; INIT_WORK(&m->process_queued_ios, process_queued_ios); INIT_WORK(&m->trigger_event, trigger_event); + init_waitqueue_head(&m->pg_init_wait); mutex_init(&m->work_mutex); m->mpio_pool = mempool_create_slab_pool(MIN_IOS, _mpio_cache); if (!m->mpio_pool) { @@ -891,9 +893,34 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc, return r; } -static void flush_multipath_work(void) +static void multipath_wait_for_pg_init_completion(struct multipath *m) +{ + DECLARE_WAITQUEUE(wait, current); + unsigned long flags; + + add_wait_queue(&m->pg_init_wait, &wait); + + while (1) { + set_current_state(TASK_UNINTERRUPTIBLE); + + spin_lock_irqsave(&m->lock, flags); + if (!m->pg_init_in_progress) { + spin_unlock_irqrestore(&m->lock, flags); + break; + } + spin_unlock_irqrestore(&m->lock, flags); + + io_schedule(); + } + set_current_state(TASK_RUNNING); + + remove_wait_queue(&m->pg_init_wait, &wait); +} + +static void flush_multipath_work(struct multipath *m) { flush_workqueue(kmpath_handlerd); + multipath_wait_for_pg_init_completion(m); flush_workqueue(kmultipathd); flush_scheduled_work(); } @@ -902,7 +929,7 @@ static void multipath_dtr(struct dm_target *ti) { struct multipath *m = ti->private; - flush_multipath_work(); + flush_multipath_work(m); free_multipath(m); } @@ -1193,6 +1220,11 @@ static void pg_init_done(void *data, int errors) queue_work(kmultipathd, &m->process_queued_ios); + /* + * Wake up any thread waiting to suspend. + */ + wake_up(&m->pg_init_wait); + out: spin_unlock_irqrestore(&m->lock, flags); } @@ -1281,7 +1313,7 @@ static void multipath_postsuspend(struct dm_target *ti) struct multipath *m = ti->private; mutex_lock(&m->work_mutex); - flush_multipath_work(); + flush_multipath_work(m); mutex_unlock(&m->work_mutex); } -- cgit v1.2.3