[PATCH] locking/lockdep: Correct calling tracepoints

From: Leo Yan
Date: Wed May 12 2021 - 08:10:33 EST


The commit eb1f00237aca ("lockdep,trace: Expose tracepoints") reverses
tracepoints for lock_contended() and lock_acquired(), thus the ftrace
log shows the wrong locking sequence that "acquired" event is prior to
"contended" event:

<idle>-0 [001] d.s3 20803.501685: lock_acquire: 0000000008b91ab4 &sg_policy->update_lock
<idle>-0 [001] d.s3 20803.501686: lock_acquired: 0000000008b91ab4 &sg_policy->update_lock
<idle>-0 [001] d.s3 20803.501689: lock_contended: 0000000008b91ab4 &sg_policy->update_lock
<idle>-0 [001] d.s3 20803.501690: lock_release: 0000000008b91ab4 &sg_policy->update_lock

This patch fixes calling tracepoints for lock_contended() and
lock_acquired().

Fixes: eb1f00237aca ("lockdep,trace: Expose tracepoints")
Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx>
---
kernel/locking/lockdep.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index 48d736aa03b2..7641bd407239 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -5736,7 +5736,7 @@ void lock_contended(struct lockdep_map *lock, unsigned long ip)
{
unsigned long flags;

- trace_lock_acquired(lock, ip);
+ trace_lock_contended(lock, ip);

if (unlikely(!lock_stat || !lockdep_enabled()))
return;
@@ -5754,7 +5754,7 @@ void lock_acquired(struct lockdep_map *lock, unsigned long ip)
{
unsigned long flags;

- trace_lock_contended(lock, ip);
+ trace_lock_acquired(lock, ip);

if (unlikely(!lock_stat || !lockdep_enabled()))
return;
--
2.25.1