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Subject: [PATCH 6/9] workqueue: Convert for_each_wq to use built-in list check (v2)
Date:   Mon, 15 Jul 2019 10:37:02 -0400
Message-Id: <20190715143705.117908-7-joel@joelfernandes.org>
In-Reply-To: <20190715143705.117908-1-joel@joelfernandes.org>
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list_for_each_entry_rcu now has support to check for RCU reader sections
as well as lock. Just use the support in it, instead of explictly
checking in the caller.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
---
 kernel/workqueue.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 601d61150b65..e882477ebf6e 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -364,11 +364,6 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
 			 !lockdep_is_held(&wq_pool_mutex),		\
 			 "RCU or wq_pool_mutex should be held")
 
-#define assert_rcu_or_wq_mutex(wq)					\
-	RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&			\
-			 !lockdep_is_held(&wq->mutex),			\
-			 "RCU or wq->mutex should be held")
-
 #define assert_rcu_or_wq_mutex_or_pool_mutex(wq)			\
 	RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&			\
 			 !lockdep_is_held(&wq->mutex) &&		\
@@ -425,9 +420,8 @@ static void workqueue_sysfs_unregister(struct workqueue_struct *wq);
  * ignored.
  */
 #define for_each_pwq(pwq, wq)						\
-	list_for_each_entry_rcu((pwq), &(wq)->pwqs, pwqs_node)		\
-		if (({ assert_rcu_or_wq_mutex(wq); false; })) { }	\
-		else
+	list_for_each_entry_rcu((pwq), &(wq)->pwqs, pwqs_node,		\
+				 lock_is_held(&(wq->mutex).dep_map))
 
 #ifdef CONFIG_DEBUG_OBJECTS_WORK
 
-- 
2.22.0.510.g264f2c817a-goog