locking/atomic, arch/mips: Convert to _relaxed atomics

Generic code will construct {,_acquire,_release} versions by adding the
required smp_mb__{before,after}_atomic() calls.

XXX if/when MIPS will start using their new SYNCxx instructions they
can provide custom __atomic_op_{acquire,release}() macros as per the
powerpc example.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
index 387ce28..0ab176b 100644 (file)
--- a/arch/mips/include/asm/atomic.h
+++ b/arch/mips/include/asm/atomic.h
@@ -79,12 +79,10 @@ static __inline__ void atomic_##op(int i, atomic_t * v)                           \
 }
 
 #define ATOMIC_OP_RETURN(op, c_op, asm_op)                                   \
-static __inline__ int atomic_##op##_return(int i, atomic_t * v)                      \
+static __inline__ int atomic_##op##_return_relaxed(int i, atomic_t * v)              \
 {                                                                            \
        int result;                                                           \
                                                                              \
-       smp_mb__before_llsc();                                                \
-                                                                             \
        if (kernel_uses_llsc && R10000_LLSC_WAR) {                            \
                int temp;                                                     \
                                                                              \
@@ -125,18 +123,14 @@ static __inline__ int atomic_##op##_return(int i, atomic_t * v)                 \
                raw_local_irq_restore(flags);                                 \
        }                                                                     \
                                                                              \
-       smp_llsc_mb();                                                        \
-                                                                             \
        return result;                                                        \
 }
 
 #define ATOMIC_FETCH_OP(op, c_op, asm_op)                                    \
-static __inline__ int atomic_fetch_##op(int i, atomic_t * v)                 \
+static __inline__ int atomic_fetch_##op##_relaxed(int i, atomic_t * v)       \
 {                                                                            \
        int result;                                                           \
                                                                              \
-       smp_mb__before_llsc();                                                \
-                                                                             \
        if (kernel_uses_llsc && R10000_LLSC_WAR) {                            \
                int temp;                                                     \
                                                                              \
@@ -176,8 +170,6 @@ static __inline__ int atomic_fetch_##op(int i, atomic_t * v)                      \
                raw_local_irq_restore(flags);                                 \
        }                                                                     \
                                                                              \
-       smp_llsc_mb();                                                        \
-                                                                             \
        return result;                                                        \
 }
 
@@ -189,6 +181,11 @@ static __inline__ int atomic_fetch_##op(int i, atomic_t * v)                     \
 ATOMIC_OPS(add, +=, addu)
 ATOMIC_OPS(sub, -=, subu)
 
+#define atomic_add_return_relaxed      atomic_add_return_relaxed
+#define atomic_sub_return_relaxed      atomic_sub_return_relaxed
+#define atomic_fetch_add_relaxed       atomic_fetch_add_relaxed
+#define atomic_fetch_sub_relaxed       atomic_fetch_sub_relaxed
+
 #undef ATOMIC_OPS
 #define ATOMIC_OPS(op, c_op, asm_op)                                         \
        ATOMIC_OP(op, c_op, asm_op)                                           \
@@ -198,6 +195,10 @@ ATOMIC_OPS(and, &=, and)
 ATOMIC_OPS(or, |=, or)
 ATOMIC_OPS(xor, ^=, xor)
 
+#define atomic_fetch_and_relaxed       atomic_fetch_and_relaxed
+#define atomic_fetch_or_relaxed                atomic_fetch_or_relaxed
+#define atomic_fetch_xor_relaxed       atomic_fetch_xor_relaxed
+
 #undef ATOMIC_OPS
 #undef ATOMIC_FETCH_OP
 #undef ATOMIC_OP_RETURN
@@ -420,12 +421,10 @@ static __inline__ void atomic64_##op(long i, atomic64_t * v)                    \
 }
 
 #define ATOMIC64_OP_RETURN(op, c_op, asm_op)                                 \
-static __inline__ long atomic64_##op##_return(long i, atomic64_t * v)        \
+static __inline__ long atomic64_##op##_return_relaxed(long i, atomic64_t * v) \
 {                                                                            \
        long result;                                                          \
                                                                              \
-       smp_mb__before_llsc();                                                \
-                                                                             \
        if (kernel_uses_llsc && R10000_LLSC_WAR) {                            \
                long temp;                                                    \
                                                                              \
@@ -467,18 +466,14 @@ static __inline__ long atomic64_##op##_return(long i, atomic64_t * v)           \
                raw_local_irq_restore(flags);                                 \
        }                                                                     \
                                                                              \
-       smp_llsc_mb();                                                        \
-                                                                             \
        return result;                                                        \
 }
 
 #define ATOMIC64_FETCH_OP(op, c_op, asm_op)                                  \
-static __inline__ long atomic64_fetch_##op(long i, atomic64_t * v)           \
+static __inline__ long atomic64_fetch_##op##_relaxed(long i, atomic64_t * v)  \
 {                                                                            \
        long result;                                                          \
                                                                              \
-       smp_mb__before_llsc();                                                \
-                                                                             \
        if (kernel_uses_llsc && R10000_LLSC_WAR) {                            \
                long temp;                                                    \
                                                                              \
@@ -519,8 +514,6 @@ static __inline__ long atomic64_fetch_##op(long i, atomic64_t * v)        \
                raw_local_irq_restore(flags);                                 \
        }                                                                     \
                                                                              \
-       smp_llsc_mb();                                                        \
-                                                                             \
        return result;                                                        \
 }
 
@@ -532,6 +525,11 @@ static __inline__ long atomic64_fetch_##op(long i, atomic64_t * v)       \
 ATOMIC64_OPS(add, +=, daddu)
 ATOMIC64_OPS(sub, -=, dsubu)
 
+#define atomic64_add_return_relaxed    atomic64_add_return_relaxed
+#define atomic64_sub_return_relaxed    atomic64_sub_return_relaxed
+#define atomic64_fetch_add_relaxed     atomic64_fetch_add_relaxed
+#define atomic64_fetch_sub_relaxed     atomic64_fetch_sub_relaxed
+
 #undef ATOMIC64_OPS
 #define ATOMIC64_OPS(op, c_op, asm_op)                                       \
        ATOMIC64_OP(op, c_op, asm_op)                                         \
@@ -541,6 +539,10 @@ ATOMIC64_OPS(and, &=, and)
 ATOMIC64_OPS(or, |=, or)
 ATOMIC64_OPS(xor, ^=, xor)
 
+#define atomic64_fetch_and_relaxed     atomic64_fetch_and_relaxed
+#define atomic64_fetch_or_relaxed      atomic64_fetch_or_relaxed
+#define atomic64_fetch_xor_relaxed     atomic64_fetch_xor_relaxed
+
 #undef ATOMIC64_OPS
 #undef ATOMIC64_FETCH_OP
 #undef ATOMIC64_OP_RETURN