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| author | David Sterba <dsterba@suse.com> | 2015-10-10 18:35:10 +0200 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2015-10-10 18:35:10 +0200 |
| commit | 33a9eca7e4a4c2c17aebbb11f0e506a48ebc30c9 (patch) | |
| tree | d7651da94ff1ef4ad27ab0ac932665fd8ef7b41c /fs/btrfs | |
| parent | b666a9cd993c6a49c4bf23a1ed476359c978f60b (diff) | |
| download | linux-33a9eca7e4a4c2c17aebbb11f0e506a48ebc30c9.tar.bz2 | |
btrfs: comment waitqueue_active implied by locks
Suggested-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs')
| -rw-r--r-- | fs/btrfs/raid56.c | 6 | ||||
| -rw-r--r-- | fs/btrfs/tree-log.c | 6 |
2 files changed, 11 insertions, 1 deletions
diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index fcf7265ca46f..1a33d3eb36de 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -810,7 +810,11 @@ static noinline void unlock_stripe(struct btrfs_raid_bio *rbio) } goto done_nolock; - } else if (waitqueue_active(&h->wait)) { + /* + * The barrier for this waitqueue_active is not needed, + * we're protected by h->lock and can't miss a wakeup. + */ + } else if (waitqueue_active(&h->wait)) { spin_unlock(&rbio->bio_list_lock); spin_unlock_irqrestore(&h->lock, flags); wake_up(&h->wait); diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 1bbaace73383..d0deb4643502 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -2950,6 +2950,9 @@ out_wake_log_root: atomic_set(&log_root_tree->log_commit[index2], 0); mutex_unlock(&log_root_tree->log_mutex); + /* + * The barrier before waitqueue_active is implied by mutex_unlock + */ if (waitqueue_active(&log_root_tree->log_commit_wait[index2])) wake_up(&log_root_tree->log_commit_wait[index2]); out: @@ -2961,6 +2964,9 @@ out: atomic_set(&root->log_commit[index1], 0); mutex_unlock(&root->log_mutex); + /* + * The barrier before waitqueue_active is implied by mutex_unlock + */ if (waitqueue_active(&root->log_commit_wait[index1])) wake_up(&root->log_commit_wait[index1]); return ret; |