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Subject[PATCH tip/core/rcu 08/21] seqlock: Remove now-redundant smp_read_barrier_depends()
Date
READ_ONCE() now implies smp_read_barrier_depends(), so this patch
removes the now-redundant smp_read_barrier_depends() from
raw_read_seqcount_latch().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
---
include/linux/seqlock.h | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index f189a8a3bbb8..bcf4cf26b8c8 100644
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -278,9 +278,8 @@ static inline void raw_write_seqcount_barrier(seqcount_t *s)

static inline int raw_read_seqcount_latch(seqcount_t *s)
{
- int seq = READ_ONCE(s->sequence);
/* Pairs with the first smp_wmb() in raw_write_seqcount_latch() */
- smp_read_barrier_depends();
+ int seq = READ_ONCE(s->sequence); /* ^^^ */
return seq;
}

--
2.5.2
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