fix missing atomic64_read_acquire on 32 bit

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/include/linux/atomic.h b/include/linux/atomic.h
index 7effc1612683eff6cd2b4c70c6ec4d7c67a3c675..7f760871ae02bdfdaeff5c118c1ad94690f33d9b 100644 (file)
--- a/include/linux/atomic.h
+++ b/include/linux/atomic.h
@@ -300,6 +300,13 @@ DEF_ATOMIC_OPS(atomic_long,        long)
 DEF_ATOMIC_OPS(atomic64,       s64)
 #else
 s64 atomic64_read(const atomic64_t *v);
+s64 atomic64_read_acquire(const atomic64_t *v)
+{
+       s64 ret = atomic64_read(v);
+       smp_mb__after_atomic();
+       return ret;
+}
+
 void atomic64_set(atomic64_t *v, s64);
 
 s64 atomic64_add_return(s64, atomic64_t *);