[PATCH v2 12/14] locking/ww_mutex: Open-code stress reorder list walk

[Kaitao Cheng]

From: Kaitao Cheng <chengkaitao@xxxxxxxxxx>

A later change will make list_for_each_entry() cache the next element
before entering the loop body. stress_reorder_work() can move list
entries while handling wound/wait locking conflicts and then continue
from the adjusted cursor.

Keep the list walk open-coded so the loop step observes the cursor
selected by the body. This preserves the existing stress-test traversal
semantics and prepares the code for the list iterator update.

Signed-off-by: Kaitao Cheng <chengkaitao@xxxxxxxxxx>
---
 kernel/locking/test-ww_mutex.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/kernel/locking/test-ww_mutex.c b/kernel/locking/test-ww_mutex.c
index 838d631544ed..08a6ab5ac041 100644
--- a/kernel/locking/test-ww_mutex.c
+++ b/kernel/locking/test-ww_mutex.c
@@ -519,7 +519,9 @@ static void stress_reorder_work(struct work_struct *work)
 	do {
 		ww_acquire_init(&ctx, stress->class);
 
-		list_for_each_entry(ll, &locks, link) {
+		for (ll = list_first_entry(&locks, typeof(*ll), link);
+		     !list_entry_is_head(ll, &locks, link);
+		     ll = list_next_entry(ll, link)) {
 			err = ww_mutex_lock(ll->lock, &ctx);
 			if (!err)
 				continue;
-- 
2.43.0