[PATCH 6.6 071/638] workqueue: Replace pwq_activate_inactive_work() with [__]pwq_activate_work()

Sasha Levin
2024-03-24T23:02:27Z

From: Tejun Heo <tj@kernel.org>

[ Upstream commit 4c6380305d21e36581b451f7337a36c93b64e050 ]

To prepare for unbound nr_active handling improvements, move work activation
part of pwq_activate_inactive_work() into __pwq_activate_work() and add
pwq_activate_work() which tests WORK_STRUCT_INACTIVE and updates nr_active.

pwq_activate_first_inactive() and try_to_grab_pending() are updated to use
pwq_activate_work(). The latter conversion is functionally identical. For
the former, this conversion adds an unnecessary WORK_STRUCT_INACTIVE
testing. This is temporary and will be removed by the next patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lai Jiangshan <jiangshanlai@gmail.com>
Stable-dep-of: 5797b1c18919 ("workqueue: Implement system-wide nr_active enforcement for unbound workqueues")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
kernel/workqueue.c | 31 +++++++++++++++++++++++++------
1 file changed, 25 insertions(+), 6 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 3eb0408133ada..3436fd266cde0 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1455,16 +1455,36 @@ static bool pwq_is_empty(struct pool_workqueue *pwq)
return !pwq->nr_active && list_empty(&pwq->inactive_works);
}

-static void pwq_activate_inactive_work(struct work_struct *work)
+static void __pwq_activate_work(struct pool_workqueue *pwq,
+ struct work_struct *work)
{
- struct pool_workqueue *pwq = get_work_pwq(work);
-
trace_workqueue_activate_work(work);
if (list_empty(&pwq->pool->worklist))
pwq->pool->watchdog_ts = jiffies;
move_linked_works(work, &pwq->pool->worklist, NULL);
__clear_bit(WORK_STRUCT_INACTIVE_BIT, work_data_bits(work));
+}
+
+/**
+ * pwq_activate_work - Activate a work item if inactive
+ * @pwq: pool_workqueue @work belongs to
+ * @work: work item to activate
+ *
+ * Returns %true if activated. %false if already active.
+ */
+static bool pwq_activate_work(struct pool_workqueue *pwq,
+ struct work_struct *work)
+{
+ struct worker_pool *pool = pwq->pool;
+
+ lockdep_assert_held(&pool->lock);
+
+ if (!(*work_data_bits(work) & WORK_STRUCT_INACTIVE))
+ return false;
+
pwq->nr_active++;
+ __pwq_activate_work(pwq, work);
+ return true;
}

static void pwq_activate_first_inactive(struct pool_workqueue *pwq)
@@ -1472,7 +1492,7 @@ static void pwq_activate_first_inactive(struct pool_workqueue *pwq)
struct work_struct *work = list_first_entry(&pwq->inactive_works,
struct work_struct, entry);

- pwq_activate_inactive_work(work);
+ pwq_activate_work(pwq, work);
}

/**
@@ -1610,8 +1630,7 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
* management later on and cause stall. Make sure the work
* item is activated before grabbing.
*/
- if (*work_data_bits(work) & WORK_STRUCT_INACTIVE)
- pwq_activate_inactive_work(work);
+ pwq_activate_work(pwq, work);

list_del_init(&work->entry);
pwq_dec_nr_in_flight(pwq, *work_data_bits(work));
--
2.43.0