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From:   "Joel Fernandes (Google)" <joel@joelfernandes.org>
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Subject: [PATCH RFC 5/5] rcuwait: Replace rcu_assign_pointer() with WRITE_ONCE
Date:   Thu, 21 Feb 2019 00:49:42 -0500
Message-Id: <20190221054942.132388-6-joel@joelfernandes.org>
In-Reply-To: <20190221054942.132388-1-joel@joelfernandes.org>
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This suppresses a sparse error generated due to the recently added
rcu_assign_pointer sparse check below. It seems WRITE_ONCE should be
sufficient here.

>> kernel//locking/percpu-rwsem.c:162:9: sparse: error: incompatible
types in comparison expression (different address spaces)

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
---
 include/linux/rcuwait.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/rcuwait.h b/include/linux/rcuwait.h
index 90bfa3279a01..9e5b4760e6c2 100644
--- a/include/linux/rcuwait.h
+++ b/include/linux/rcuwait.h
@@ -44,7 +44,7 @@ extern void rcuwait_wake_up(struct rcuwait *w);
 	 */                                                             \
 	WARN_ON(current->exit_state);                                   \
 									\
-	rcu_assign_pointer((w)->task, current);				\
+	WRITE_ONCE((w)->task, current);					\
 	for (;;) {							\
 		/*							\
 		 * Implicit barrier (A) pairs with (B) in		\
-- 
2.21.0.rc0.258.g878e2cd30e-goog