summaryrefslogtreecommitdiff
path: root/fs
diff options
context:
space:
mode:
authorGoldwyn Rodrigues <rgoldwyn@suse.com>2019-09-11 11:45:15 -0500
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-01-17 19:45:46 +0100
commitf04fb2025339f90d65c3473250c4ee8b6f482a60 (patch)
tree5d1e75d8ca22519436e3ba1c00603a6bace82ac4 /fs
parent7ffb1ac23fcc687db2624e09bde36a8deced6ac0 (diff)
btrfs: simplify inode locking for RWF_NOWAIT
commit 9cf35f673583ccc9f3e2507498b3079d56614ad3 upstream. This is similar to 942491c9e6d6 ("xfs: fix AIM7 regression"). Apparently our current rwsem code doesn't like doing the trylock, then lock for real scheme. This causes extra contention on the lock and can be measured eg. by AIM7 benchmark. So change our read/write methods to just do the trylock for the RWF_NOWAIT case. Fixes: edf064e7c6fe ("btrfs: nowait aio support") Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> [ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
-rw-r--r--fs/btrfs/file.c5
1 files changed, 3 insertions, 2 deletions
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index bf654d48eb46..97be32da857a 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1890,9 +1890,10 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb,
(iocb->ki_flags & IOCB_NOWAIT))
return -EOPNOTSUPP;
- if (!inode_trylock(inode)) {
- if (iocb->ki_flags & IOCB_NOWAIT)
+ if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (!inode_trylock(inode))
return -EAGAIN;
+ } else {
inode_lock(inode);
}