backing-dev: use synchronize_rcu_expedited instead of synchronize_rcu synchronize_rcu sleeps several timer ticks. When removing thousands block devices, this sleeping causes a severe delay. Signed-off-by: Mikulas Patocka --- mm/backing-dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: linux-3.0-rc7-fast/mm/backing-dev.c =================================================================== --- linux-3.0-rc7-fast.orig/mm/backing-dev.c 2011-07-19 18:01:00.000000000 +0200 +++ linux-3.0-rc7-fast/mm/backing-dev.c 2011-07-19 18:01:07.000000000 +0200 @@ -505,7 +505,7 @@ static void bdi_remove_from_list(struct list_del_rcu(&bdi->bdi_list); spin_unlock_bh(&bdi_lock); - synchronize_rcu(); + synchronize_rcu_expedited(); } int bdi_register(struct backing_dev_info *bdi, struct device *parent,