From 6daf3de34b1729fcdfcccb303bb642b57548a00c Mon Sep 17 00:00:00 2001
From: Qu Wenruo <wqu@suse.com>
Date: Thu, 13 Jun 2024 09:58:48 +0930
Subject: [PATCH] btrfs-progs: tests: always wait for subvolume cleaning before
 clear-stale

[BUG]
There is a random chance that misc/055 would fail with stale qgroups
detected.

[CAUSE]
Commit 82f7d6c1d711 ("btrfs-progs: qgroup: handle stale qgroup deletion
more accurately") changed the behavior of "btrfs qgroup clear-stale"
that it will no longer try to remove qgroup under deletion.

And the test case itself relies on the return value of "btrfs qgroup
clear-stale" to do the extra wait for subvolume deletion.

This means after that commit, the test case would skip the wait if there
is a subvolume waiting for cleanup, resulting in a race window where the
subvolume can be dropped and become stale, and eventually trigger the
stale qgroup detection and cause false alerts.

[FIX]
Fix the test case by always wait for the subvolume to be dropped, so
that later "btrfs qgroup clear-stale" can properly remove all stale
qgroups.

Pull-request: #814
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---
 tests/misc-tests/055-qgroup-clear-stale/test.sh | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/tests/misc-tests/055-qgroup-clear-stale/test.sh b/tests/misc-tests/055-qgroup-clear-stale/test.sh
index 3e029885..b0edf869 100755
--- a/tests/misc-tests/055-qgroup-clear-stale/test.sh
+++ b/tests/misc-tests/055-qgroup-clear-stale/test.sh
@@ -18,14 +18,15 @@ run_check $SUDO_HELPER "$TOP/btrfs" qgroup show "$TEST_MNT"
 rootid=$(run_check_stdout "$TOP/btrfs" inspect-internal rootid "$TEST_MNT/subv1")
 run_check $SUDO_HELPER "$TOP/btrfs" subvolume delete "$TEST_MNT/subv1"
 run_check $SUDO_HELPER "$TOP/btrfs" qgroup show "$TEST_MNT"
-# Subvolume deletion could be slow and won't let the qgroup to be cleaned,
-# shown as '<under deletion>'.
-if ! run_mayfail $SUDO_HELPER "$TOP/btrfs" qgroup clear-stale "$TEST_MNT"; then
-	run_check $SUDO_HELPER "$TOP/btrfs" subvolume sync "$TEST_MNT" "$rootid"
-	run_check $SUDO_HELPER "$TOP/btrfs" qgroup show "$TEST_MNT"
-	# After cleaning the subvolume it must pass
-	run_check $SUDO_HELPER "$TOP/btrfs" qgroup clear-stale "$TEST_MNT"
-fi
+
+# Subvolume under deletion won't be deleted and "btrfs qgroup clear-stale"
+# would detect it and not report an error.
+# So here we have to wait for the subvolume deletion.
+run_check $SUDO_HELPER "$TOP/btrfs" subvolume sync "$TEST_MNT" "$rootid"
+run_check $SUDO_HELPER "$TOP/btrfs" qgroup show "$TEST_MNT"
+# After cleaning the subvolume it must pass
+run_check $SUDO_HELPER "$TOP/btrfs" qgroup clear-stale "$TEST_MNT"
+
 list=$(run_check_stdout $SUDO_HELPER "$TOP/btrfs" qgroup show "$TEST_MNT")
 if echo "$list" | grep -q "0/$rootid"; then
 	_fail "stale qgroups not deleted"