MIPS: atomic: Use _atomic barriers in atomic_sub_if_positive()

Use smp_mb__before_atomic() & smp_mb__after_atomic() in
atomic_sub_if_positive() rather than the equivalent
smp_mb__before_llsc() & smp_llsc_mb(). The former are more standard &
this preps us for avoiding redundant duplicate barriers on Loongson3 in
a later patch.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org

diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
index 841ff27..24443ef 100644 (file)
--- a/arch/mips/include/asm/atomic.h
+++ b/arch/mips/include/asm/atomic.h
@@ -196,7 +196,7 @@ static __inline__ int atomic_sub_if_positive(int i, atomic_t * v)
 {
        int result;
 
-       smp_mb__before_llsc();
+       smp_mb__before_atomic();
 
        if (kernel_uses_llsc) {
                int temp;
@@ -237,7 +237,7 @@ static __inline__ int atomic_sub_if_positive(int i, atomic_t * v)
         * another barrier here.
         */
        if (!__SYNC_loongson3_war)
-               smp_llsc_mb();
+               smp_mb__after_atomic();
 
        return result;
 }