svn commit: r292369 - in projects/zfsd/head/tests/sys/cddl/zfs: include tests/redundancy

[Alan Somers]

Author: asomers
Date: Wed Dec 16 21:05:44 2015
New Revision: 292369
URL: https://svnweb.freebsd.org/changeset/base/292369

Log:
  Add a function that syncs to stable storage, not just the ZIL.
  
  Use it to try to stamp out intermittent failures in the ZFS test suite's
  redundancy tests.
  
  tests/sys/cddl/zfs/include/libtest.kshlib:
  	- Add force_sync_path(), which (ab)uses the fact that 'zpool
  	  history' always does a txg_wait_synced() for its first ioctl call.
  	  sync(8) doesn't have the flexibility to handle this type of call,
  	  and there isn't a better option available that does not mutate the
  	  pool.
  	- Leave a XXX comment to flag this implementation as a hack.
  	- Some history: Previously, I had changed zfs_sync(), ZFS's
  	  VFS_SYNC(9), so that it would call txg_wait_synced(), as a
  	  workaround for a performance drop off issue.  gibbs later fixed
  	  this by changing zfs_sync() to ignore syncer(4)'s periodic
  	  requests to sync to stable storage, and reverted the
  	  txg_wait_synced() call back to zil_commit().
  
  tests/sys/cddl/zfs/tests/redundancy/redundancy.kshlib:
  	- Use foce_sync_path instead of $SYNC for the redundancy test suite,
  	  which relies on the data actually getting written to the target
  	  devices so they can be corrupted directly.  These may not be the
  	  only place this would be useful, but this is somewhat of an
  	  experiment to determine whether the intermittent failures stop.
  
  Submitted by:	Will
  Sponsored by:	Spectra Logic Corp

Modified:
  projects/zfsd/head/tests/sys/cddl/zfs/include/libtest.kshlib
  projects/zfsd/head/tests/sys/cddl/zfs/tests/redundancy/redundancy.kshlib

Modified: projects/zfsd/head/tests/sys/cddl/zfs/include/libtest.kshlib
==============================================================================
--- projects/zfsd/head/tests/sys/cddl/zfs/include/libtest.kshlib	Wed Dec 16 21:03:52 2015	(r292368)
+++ projects/zfsd/head/tests/sys/cddl/zfs/include/libtest.kshlib	Wed Dec 16 21:05:44 2015	(r292369)
@@ -2696,6 +2696,25 @@ function gen_dataset_name
 }
 
 #
+# Ensure that a given path has been synced, not just ZIL committed.
+#
+# XXX The implementation currently requires calling 'zpool history'.  On
+#     FreeBSD, the sync(8) command (via $SYNC) calls zfs_sync() which just
+#     does a zil_commit(), as opposed to a txg_wait_synced().  For things that
+#     require writing to their final destination (e.g. for intentional
+#     corruption purposes), zil_commit() is not good enough.
+#
+function force_sync_path # path
+{
+	typeset path="$1"
+
+	zfspath=$($DF $path 2>/dev/null | tail -1 | cut -d" " -f1 | cut -d/ -f1)
+	[ -z "$zfspath" ] && return false
+	log_note "Force syncing ${zfspath} for ${path} ..."
+	$ZPOOL history $zfspath >/dev/null 2>&1
+}
+
+#
 # Get cksum tuple of dataset
 # $1 dataset name
 #

Modified: projects/zfsd/head/tests/sys/cddl/zfs/tests/redundancy/redundancy.kshlib
==============================================================================
--- projects/zfsd/head/tests/sys/cddl/zfs/tests/redundancy/redundancy.kshlib	Wed Dec 16 21:03:52 2015	(r292368)
+++ projects/zfsd/head/tests/sys/cddl/zfs/tests/redundancy/redundancy.kshlib	Wed Dec 16 21:05:44 2015	(r292369)
@@ -95,7 +95,7 @@ function setup_test_env
 
 	typeset file=$TESTDIR/file
 	log_must $FILE_WRITE -o create -f $file -b $BLOCKSZ -c $NUM_WRITES
-	log_must $SYNC $TESTDIR
+	log_must force_sync_path $TESTDIR
 	record_data $TESTPOOL $PRE_RECORD_FILE
 }
 
@@ -139,8 +139,7 @@ function sync_pool #pool
 {
 	typeset pool=$1
 
-	log_must $SYNC
-	log_must $SLEEP 2
+	log_must force_sync_path $pool
 
 	# If the OS has detected corruption on the pool, it will have
 	# automatically initiated a scrub.  In that case, our "zpool scrub"