lcoking/barriers, arch: Use smp barriers in smp_store_release()

With commit b92b8b35a2e ("locking/arch: Rename set_mb() to smp_store_mb()")
it was made clear that the context of this call (and thus set_mb)
is strictly for CPU ordering, as opposed to IO. As such all archs
should use the smp variant of mb(), respecting the semantics and
saving a mandatory barrier on UP.

Signed-off-by: Davidlohr Bueso <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

diff --git a/arch/ia64/include/asm/barrier.h b/arch/ia64/include/asm/barrier.h
index df896a1c41d348e60641bb0f89aece2d5ba95f93..209c4b817c958e25eea0298afe121fc225f1e9e3 100644 (file)
--- a/arch/ia64/include/asm/barrier.h
+++ b/arch/ia64/include/asm/barrier.h
@@ -77,7 +77,7 @@ do {                                                                  \
        ___p1;                                                          \
 })
 
-#define smp_store_mb(var, value)       do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); smp_mb(); } while (0)
 
 /*
  * The group barrier in front of the rsm & ssm are necessary to ensure

diff --git a/arch/powerpc/include/asm/barrier.h b/arch/powerpc/include/asm/barrier.h
index 0eca6efc0631d52adcdd3bd66ad88bb7d33f830d..a7af5fb7b91476148e9ee2ce44d4d93ed3ad70fd 100644 (file)
--- a/arch/powerpc/include/asm/barrier.h
+++ b/arch/powerpc/include/asm/barrier.h
@@ -34,7 +34,7 @@
 #define rmb()  __asm__ __volatile__ ("sync" : : : "memory")
 #define wmb()  __asm__ __volatile__ ("sync" : : : "memory")
 
-#define smp_store_mb(var, value)       do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value) do { WRITE_ONCE(var, value); smp_mb(); } while (0)
 
 #ifdef __SUBARCH_HAS_LWSYNC
 #    define SMPWMB      LWSYNC

diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
index d68e11e0df5eada7e600f58529e8cbe60fab41c7..7ffd0b19135c8d46770f1f37ca6d4da19e352de0 100644 (file)
--- a/arch/s390/include/asm/barrier.h
+++ b/arch/s390/include/asm/barrier.h
@@ -36,7 +36,7 @@
 #define smp_mb__before_atomic()                smp_mb()
 #define smp_mb__after_atomic()         smp_mb()
 
-#define smp_store_mb(var, value)               do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value)       do { WRITE_ONCE(var, value); smp_mb(); } while (0)
 
 #define smp_store_release(p, v)                                                \
 do {                                                                   \

diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index b42afada1280e08534d6e98fbf9364b3dcae9d8a..0f45f93ef6922ba1417966ba99680a96f81a19f9 100644 (file)
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h
@@ -93,7 +93,7 @@
 #endif /* CONFIG_SMP */
 
 #ifndef smp_store_mb
-#define smp_store_mb(var, value)  do { WRITE_ONCE(var, value); mb(); } while (0)
+#define smp_store_mb(var, value)  do { WRITE_ONCE(var, value); smp_mb(); } while (0)
 #endif
 
 #ifndef smp_mb__before_atomic