Merge tag 'acpi-4.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...

[linux-2.6-block.git] / include / linux / seqlock.h

diff --git a/include/linux/seqlock.h b/include/linux/seqlock.h
index 7973a821ac58877a56ff5214793786948170ae8e..ead97654c4e9afa7239e068cb37f6981d77ce6a3 100644 (file)
--- a/include/linux/seqlock.h
+++ b/include/linux/seqlock.h
@@ -277,7 +277,10 @@ static inline void raw_write_seqcount_barrier(seqcount_t *s)
 
 static inline int raw_read_seqcount_latch(seqcount_t *s)
 {
-       return lockless_dereference(s)->sequence;
+       int seq = READ_ONCE(s->sequence);
+       /* Pairs with the first smp_wmb() in raw_write_seqcount_latch() */
+       smp_read_barrier_depends();
+       return seq;
 }
 
 /**
@@ -331,7 +334,7 @@ static inline int raw_read_seqcount_latch(seqcount_t *s)
  *     unsigned seq, idx;
  *
  *     do {
- *             seq = lockless_dereference(latch)->seq;
+ *             seq = raw_read_seqcount_latch(&latch->seq);
  *
  *             idx = seq & 0x01;
  *             entry = data_query(latch->data[idx], ...);