From 3508e6590d4729ac07f01f7ae2256c2f9dc738b8 Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Wed, 29 Jul 2015 14:11:28 -0400 Subject: [PATCH] Revert "dm cache: do not wake_worker() in free_migration()" This reverts commit 386cb7cdeeef97e0bf082a8d6bbfc07a2ccce07b. Taking the wake_worker() out of free_migration() will slow writeback dramatically, and hence adaptability. Say we have 10k blocks that need writing back, but are only able to issue 5 concurrently due to the migration bandwidth: it's imperative that we wake_worker() immediately after migration completion; waiting for the next 1 second wake up (via do_waker) means it'll take a long time to write that all back. Reported-by: Joe Thornber Signed-off-by: Mike Snitzer --- drivers/md/dm-cache-target.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index b680da5d7b93..64e96a2bed58 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -424,6 +424,7 @@ static void free_migration(struct dm_cache_migration *mg) wake_up(&cache->migration_wait); mempool_free(mg, cache->migration_pool); + wake_worker(cache); } static int prealloc_data_structs(struct cache *cache, struct prealloc *p) -- 2.20.1