From: Jeff Layton <jlayton@redhat.com>
Date: Tue, 28 Sep 2010 13:14:01 +0000 (-0400)
Subject: NFS: don't use FLUSH_SYNC on WB_SYNC_NONE COMMIT calls (try #2)
X-Git-Tag: firefly_0821_release~7613^2~3643^2~32
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a00dd6c03dd97a777c291a8af8682be4b5fadf8d;p=firefly-linux-kernel-4.4.55.git

NFS: don't use FLUSH_SYNC on WB_SYNC_NONE COMMIT calls (try #2)

WB_SYNC_NONE is supposed to mean "don't wait on anything". That should
also include not waiting for COMMIT calls to complete.

WB_SYNC_NONE is also implied when wbc->nonblocking and
wbc->for_background are set, so we can replace those checks in
nfs_commit_unstable_pages with a check for WB_SYNC_NONE.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 4d6d35dd2b4b..605e292501f4 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1431,15 +1431,17 @@ static int nfs_commit_unstable_pages(struct inode *inode, struct writeback_contr
 	int flags = FLUSH_SYNC;
 	int ret = 0;
 
-	/* Don't commit yet if this is a non-blocking flush and there are
-	 * lots of outstanding writes for this mapping.
-	 */
-	if (wbc->sync_mode == WB_SYNC_NONE &&
-	    nfsi->ncommit <= (nfsi->npages >> 1))
-		goto out_mark_dirty;
+	if (wbc->sync_mode == WB_SYNC_NONE) {
+		/* Don't commit yet if this is a non-blocking flush and there
+		 * are a lot of outstanding writes for this mapping.
+		 */
+		if (nfsi->ncommit <= (nfsi->npages >> 1))
+			goto out_mark_dirty;
 
-	if (wbc->nonblocking || wbc->for_background)
+		/* don't wait for the COMMIT response */
 		flags = 0;
+	}
+
 	ret = nfs_commit_inode(inode, flags);
 	if (ret >= 0) {
 		if (wbc->sync_mode == WB_SYNC_NONE) {