diff options
| author | Trond Myklebust <trond.myklebust@primarydata.com> | 2017-07-17 09:30:13 -0400 |
|---|---|---|
| committer | Trond Myklebust <trond.myklebust@primarydata.com> | 2017-08-15 11:54:46 -0400 |
| commit | 82749dd4efcec8e90fa7769eec3dd0afa2e3396a (patch) | |
| tree | 0e8c3f768d8ab4e91944893624dcb73ef8e557e7 /fs/nfs | |
| parent | 6d17d653c9f152e113043d00f3bcf00c0eb5f5a2 (diff) | |
NFS: Reduce lock contention in nfs_page_find_head_request()
Add a lockless check for whether or not the page might be carrying
an existing writeback before we grab the inode->i_lock.
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Diffstat (limited to 'fs/nfs')
| -rw-r--r-- | fs/nfs/write.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 1d447e37f472..06e150c4e315 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -190,9 +190,11 @@ static struct nfs_page *nfs_page_find_head_request(struct page *page) struct inode *inode = page_file_mapping(page)->host; struct nfs_page *req = NULL; - spin_lock(&inode->i_lock); - req = nfs_page_find_head_request_locked(NFS_I(inode), page); - spin_unlock(&inode->i_lock); + if (PagePrivate(page) || PageSwapCache(page)) { + spin_lock(&inode->i_lock); + req = nfs_page_find_head_request_locked(NFS_I(inode), page); + spin_unlock(&inode->i_lock); + } return req; } |