[PATCH v2 2/5] workqueue: Change workqueue lockdep map to pointer

From: Matthew Brost
Date: Tue Jul 30 2024 - 20:30:52 EST


Will help enable user-defined lockdep maps for workqueues.

Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Lai Jiangshan <jiangshanlai@xxxxxxxxx>
Signed-off-by: Matthew Brost <matthew.brost@xxxxxxxxx>
---
kernel/workqueue.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index c9bdd6a23a2b..b3fa4d044f69 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -366,7 +366,8 @@ struct workqueue_struct {
#ifdef CONFIG_LOCKDEP
char *lock_name;
struct lock_class_key key;
- struct lockdep_map lockdep_map;
+ struct lockdep_map __lockdep_map;
+ struct lockdep_map *lockdep_map;
#endif
char name[WQ_NAME_LEN]; /* I: workqueue name */

@@ -3220,7 +3221,7 @@ __acquires(&pool->lock)
lockdep_start_depth = lockdep_depth(current);
/* see drain_dead_softirq_workfn() */
if (!bh_draining)
- lock_map_acquire(&pwq->wq->lockdep_map);
+ lock_map_acquire(pwq->wq->lockdep_map);
lock_map_acquire(&lockdep_map);
/*
* Strictly speaking we should mark the invariant state without holding
@@ -3254,7 +3255,7 @@ __acquires(&pool->lock)
pwq->stats[PWQ_STAT_COMPLETED]++;
lock_map_release(&lockdep_map);
if (!bh_draining)
- lock_map_release(&pwq->wq->lockdep_map);
+ lock_map_release(pwq->wq->lockdep_map);

if (unlikely((worker->task && in_atomic()) ||
lockdep_depth(current) != lockdep_start_depth ||
@@ -3892,8 +3893,8 @@ static void touch_wq_lockdep_map(struct workqueue_struct *wq)
if (wq->flags & WQ_BH)
local_bh_disable();

- lock_map_acquire(&wq->lockdep_map);
- lock_map_release(&wq->lockdep_map);
+ lock_map_acquire(wq->lockdep_map);
+ lock_map_release(wq->lockdep_map);

if (wq->flags & WQ_BH)
local_bh_enable();
@@ -3927,7 +3928,7 @@ void __flush_workqueue(struct workqueue_struct *wq)
struct wq_flusher this_flusher = {
.list = LIST_HEAD_INIT(this_flusher.list),
.flush_color = -1,
- .done = COMPLETION_INITIALIZER_ONSTACK_MAP(this_flusher.done, wq->lockdep_map),
+ .done = COMPLETION_INITIALIZER_ONSTACK_MAP(this_flusher.done, (*wq->lockdep_map)),
};
int next_color;

@@ -4788,7 +4789,8 @@ static void wq_init_lockdep(struct workqueue_struct *wq)
lock_name = wq->name;

wq->lock_name = lock_name;
- lockdep_init_map(&wq->lockdep_map, lock_name, &wq->key, 0);
+ wq->lockdep_map = &wq->__lockdep_map;
+ lockdep_init_map(wq->lockdep_map, lock_name, &wq->key, 0);
}

static void wq_unregister_lockdep(struct workqueue_struct *wq)
--
2.34.1