[PATCH] xfs/011: support byte-based grant heads are stored in bytes now

[Christoph Hellwig <hch@lst.de>]

New kernels where reservation grant track the actual reservation space
consumed in bytes instead of LSNs in cycle/block tuples export different
sysfs files for this information.

Adapt the test to detect which version is exported, and simply check
for a near-zero reservation space consumption for the byte based version.

Based on work from Dave Chinner.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 tests/xfs/011 | 67 +++++++++++++++++++++++++++++++++------------------
 1 file changed, 44 insertions(+), 23 deletions(-)

diff --git a/tests/xfs/011 b/tests/xfs/011
index ed44d074b..ef2366adf 100755
--- a/tests/xfs/011
+++ b/tests/xfs/011
@@ -11,7 +11,18 @@
 . ./common/preamble
 _begin_fstest auto freeze log metadata quick
 
-# Import common functions.
+# real QA test starts here
+_supported_fs xfs
+
+_require_scratch
+_require_freeze
+_require_xfs_sysfs $(_short_dev $TEST_DEV)/log
+_require_command "$KILLALL_PROG" killall
+
+. ./common/filter
+
+devname=`_short_dev $SCRATCH_DEV`
+attrprefix="/sys/fs/xfs/$devname/log"
 
 # Override the default cleanup function.
 _cleanup()
@@ -24,27 +35,29 @@ _cleanup()
 	rm -f $tmp.*
 }
 
-# Use the information exported by XFS to sysfs to determine whether the log has
-# active reservations after a filesystem freeze.
-_check_scratch_log_state()
+_check_scratch_log_state_new()
 {
-	devname=`_short_dev $SCRATCH_DEV`
-	attrpath="/sys/fs/xfs/$devname/log"
-
-	# freeze the fs to ensure data is synced and the log is flushed. this
-	# means no outstanding transactions, and thus no outstanding log
-	# reservations, should exist
-	xfs_freeze -f $SCRATCH_MNT
+	# The grant heads record reservations in bytes.  For complex reasons
+	# beyond the scope fo this test, these aren't going to be exactly zero
+	# for frozen filesystems. Hence just check the value is between 0 and
+	# the maximum iclog size (256kB).
+	for attr in "reserve_grant_head_bytes" "write_grant_head_bytes"; do
+		space=`cat $attrprefix/$attr`
+		_within_tolerance $space 1024 0 $((256 * 1024))
+	done
+}
 
+_check_scratch_log_state_old()
+{
 	# the log head is exported in basic blocks and the log grant heads in
 	# bytes. convert the log head to bytes for precise comparison
-	log_head_cycle=`awk -F : '{ print $1 }' $attrpath/log_head_lsn`
-	log_head_bytes=`awk -F : '{ print $2 }' $attrpath/log_head_lsn`
+	log_head_cycle=`awk -F : '{ print $1 }' $attrprefix/log_head_lsn`
+	log_head_bytes=`awk -F : '{ print $2 }' $attrprefix/log_head_lsn`
 	log_head_bytes=$((log_head_bytes * 512))
 
 	for attr in "reserve_grant_head" "write_grant_head"; do
-		cycle=`cat $attrpath/$attr | awk -F : '{ print $1 }'`
-		bytes=`cat $attrpath/$attr | awk -F : '{ print $2 }'`
+		cycle=`cat $attrprefix/$attr | awk -F : '{ print $1 }'`
+		bytes=`cat $attrprefix/$attr | awk -F : '{ print $2 }'`
 
 		if [ $cycle != $log_head_cycle ] ||
 		   [ $bytes != $log_head_bytes ]
@@ -54,17 +67,25 @@ _check_scratch_log_state()
 				"possible leak detected."
 		fi
 	done
-
-	xfs_freeze -u $SCRATCH_MNT
 }
 
-# real QA test starts here
-_supported_fs xfs
+# Use the information exported by XFS to sysfs to determine whether the log has
+# active reservations after a filesystem freeze.
+_check_scratch_log_state()
+{
+	# freeze the fs to ensure data is synced and the log is flushed. this
+	# means no outstanding transactions, and thus no outstanding log
+	# reservations, should exist
+	xfs_freeze -f $SCRATCH_MNT
 
-_require_scratch
-_require_freeze
-_require_xfs_sysfs $(_short_dev $TEST_DEV)/log
-_require_command "$KILLALL_PROG" killall
+	if [ -f "${attrprefix}/reserve_grant_head_bytes" ]; then
+	    _check_scratch_log_state_new
+	else
+	    _check_scratch_log_state_old
+	fi
+
+	xfs_freeze -u $SCRATCH_MNT
+}
 
 echo "Silence is golden."
 
-- 
2.43.0