From 53176dde0acd8fa49c6c2e6097283acc6241480f Mon Sep 17 00:00:00 2001 From: David Sterba Date: Thu, 5 Apr 2018 01:41:06 +0200 Subject: btrfs: dev-replace: remove custom read/write blocking scheme After the rw semaphore has been added, the custom blocking using ::blocking_readers and ::read_lock_wq is redundant. The blocking logic in __btrfs_map_block is replaced by extending the time the semaphore is held, that has the same blocking effect on writes as the previous custom scheme that waited until ::blocking_readers was zero. Signed-off-by: David Sterba --- fs/btrfs/dev-replace.c | 16 ---------------- 1 file changed, 16 deletions(-) (limited to 'fs/btrfs/dev-replace.c') diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c index 316a29278306..a71661f43dec 100644 --- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -1012,14 +1012,7 @@ void btrfs_dev_replace_read_unlock(struct btrfs_dev_replace *dev_replace) void btrfs_dev_replace_write_lock(struct btrfs_dev_replace *dev_replace) { -again: - wait_event(dev_replace->read_lock_wq, - atomic_read(&dev_replace->blocking_readers) == 0); down_write(&dev_replace->rwsem); - if (atomic_read(&dev_replace->blocking_readers)) { - up_write(&dev_replace->rwsem); - goto again; - } } void btrfs_dev_replace_write_unlock(struct btrfs_dev_replace *dev_replace) @@ -1027,15 +1020,6 @@ void btrfs_dev_replace_write_unlock(struct btrfs_dev_replace *dev_replace) up_write(&dev_replace->rwsem); } -/* inc blocking cnt and release read lock */ -void btrfs_dev_replace_set_lock_blocking( - struct btrfs_dev_replace *dev_replace) -{ - /* only set blocking for read lock */ - atomic_inc(&dev_replace->blocking_readers); - up_read(&dev_replace->rwsem); -} - void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info) { percpu_counter_inc(&fs_info->dev_replace.bio_counter); -- cgit v1.2.3