[PATCH V2] loosen input requirements on defrag testing

Eric Sandeen
2015-12-02T22:09:28Z

We don't have perfect control of file allocation for these tests;
in some cases we may fail to adequately fragment a file prior to
defragmentation testing, and today that will fail the test.

Attack this on 2 fronts:

1) Explicitly allow fewer extents on one of the input files in
generic/018 where the allocator has discretion.
2) _notrun rather than _fail if we don't create enough extents;
this is a defrag test, not an allocator/fragmentation test,
so just skip the test if we can't create an acceptable file
for defrag testing.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
---

V2 fix args to _defrag and fix 018.out. what the ... I swear I tested
this... :/ This time for realz.

diff --git a/common/defrag b/common/defrag
index f923dc0..d2b137e 100644
--- a/common/defrag
+++ b/common/defrag
@@ -53,15 +53,24 @@ _check_extent_count()
max=$2
ext_cnt=$3

- [ "$min" -gt "$ext_cnt" ] && _fail "Found $ext_cnt extents min:$max"
- [ "$max" -ne -1 ] && [ "$ext_cnt" -gt "$max" ] && _fail "Found $ext_cnt max: $max"
+ # Return failure if $3 isn't between $1 and $2; let caller decide
+ # action if it's not, we just return status here.
+ if [ "$min" -gt "$ext_cnt" ]; then
+ echo "Found $ext_cnt extents min:$max"
+ return 1;
+ fi
+ if [ "$max" -ne -1 ] && [ "$ext_cnt" -gt "$max" ]; then
+ echo "Found $ext_cnt max: $max"
+ return 1;
+ fi

if [ $max -ne $min ]; then
echo "in_range($min, $max)"
else
echo "$ext_cnt"
fi
- return $ext_cnt
+ # success
+ return 0
}

# Defrag file, check it, and remove it.
@@ -129,6 +138,7 @@ _defrag()
echo -n "Before: "
ext_before=$(_extent_count $1)
_check_extent_count $min_before $max_before $ext_before
+ [ $? -eq 0 ] || _notrun "Could not adequately fragment file"

[ ! -z $csum ] && CSUM_BEFORE=`md5sum $1`
STAT_BEFORE=`stat -c "a: %x m: %y c: %z" $1`
@@ -141,6 +151,7 @@ _defrag()
echo -n "After: "
ext_after=$(_extent_count $1)
_check_extent_count $min_after $max_after $ext_after
+ [ $? -eq 0 ] || _fail "Failed to adequately defragment file"

[ "$ext_before" -lt "$ext_after" ] && \
_fail "Number of extents increased after defragmentation," \
diff --git a/tests/generic/018 b/tests/generic/018
index d97bb88..e8dbab3 100755
--- a/tests/generic/018
+++ b/tests/generic/018
@@ -77,7 +77,9 @@ for i in `seq 9 -1 0`; do
$XFS_IO_PROG -fs -c "pwrite -b $bsize $((i * bsize)) $bsize" $fragfile \
> /dev/null
done
-_defrag --before 10 --after 1 $fragfile
+
+# Accept fewer fragments than we might expect; we don't have perfect control.
+_defrag --max_before 10 --min_before 5 --after 1 $fragfile

echo "Write backwards sync leaving holes - defrag should do nothing" | tee -a $seqres.full
for i in `seq 31 -2 0`; do
diff --git a/tests/generic/018.out b/tests/generic/018.out
index 5f265d1..1746b32 100644
--- a/tests/generic/018.out
+++ b/tests/generic/018.out
@@ -9,7 +9,7 @@ Contiguous file:
Before: 1
After: 1
Write backwards sync, but contiguous - should defrag to 1 extent
-Before: 10
+Before: in_range(5, 10)
After: 1
Write backwards sync leaving holes - defrag should do nothing
Before: 16