svn commit: r297081 - stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs

[Alexander Motin]

Author: mav
Date: Sun Mar 20 20:25:36 2016
New Revision: 297081
URL: https://svnweb.freebsd.org/changeset/base/297081

Log:
  MFC r277503 (by will): Ignore sync requests from the system syncher,
  i.e. VFS_SYNC(waitfor=MNT_LAZY).
  
  ZFS already commits outstanding data every zfs_txg_timeout seconds, so these
  syncs are unnecessarily intrusive.
  
  MFSpectraBSD:   1105759 on 2014/12/11

Modified:
  stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c
==============================================================================
--- stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c	Sun Mar 20 20:23:20 2016	(r297080)
+++ stable/10/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c	Sun Mar 20 20:25:36 2016	(r297081)
@@ -133,6 +133,13 @@ zfs_sync(vfs_t *vfsp, int waitfor)
 	if (panicstr)
 		return (0);
 
+	/*
+	 * Ignore the system syncher.  ZFS already commits async data
+	 * at zfs_txg_timeout intervals.
+	 */
+	if (waitfor == MNT_LAZY)
+		return (0);
+
 	if (vfsp != NULL) {
 		/*
 		 * Sync a specific filesystem.