[PATCH 3/8] generic/192: fix spurious timeout

Darrick J. Wong
2024-02-27T02:01:19Z

From: Darrick J. Wong <djwong@kernel.org>

I have a theory that when the nfs server that hosts the root fs for my
testing VMs gets backed up, it can take a while for path resolution and
loading of echo, cat, or tee to finish. That delays the test enough to
result in:

--- /tmp/fstests/tests/generic/192.out 2023-11-29 15:40:52.715517458 -0800
+++ /var/tmp/fstests/generic/192.out.bad 2023-12-15 21:28:02.860000000 -0800
@@ -1,5 +1,6 @@
QA output created by 192
sleep for 5 seconds
test
-delta1 is in range
+delta1 has value of 12
+delta1 is NOT in range 5 .. 7
delta2 is in range

Therefore, invoke all these utilities with --help before the critical
section to make sure they're all in memory.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
tests/generic/192 | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/tests/generic/192 b/tests/generic/192
index 0d3cd03b4b..2825486635 100755
--- a/tests/generic/192
+++ b/tests/generic/192
@@ -29,17 +29,27 @@ delay=5
testfile=$TEST_DIR/testfile
rm -f $testfile

+# Preload every binary used between sampling time1 and time2 so that loading
+# them has minimal overhead even if the root fs is hosted over a slow network.
+# Also don't put pipe and tee creation in that critical section.
+for i in echo stat sleep cat; do
+ $i --help &>/dev/null
+done
+
echo test >$testfile
-time1=`_access_time $testfile | tee -a $seqres.full`
+time1=`_access_time $testfile`
+echo $time1 >> $seqres.full

echo "sleep for $delay seconds"
sleep $delay # sleep to allow time to move on for access
cat $testfile
-time2=`_access_time $testfile | tee -a $seqres.full`
+time2=`_access_time $testfile`
+echo $time2 >> $seqres.full

cd /
_test_cycle_mount
-time3=`_access_time $testfile | tee -a $seqres.full`
+time3=`_access_time $testfile`
+echo $time3 >> $seqres.full

delta1=`expr $time2 - $time1`
delta2=`expr $time3 - $time1`