s390/atomic: make use of interlocked-access facility 1 instructions
authorHeiko Carstens <heiko.carstens@de.ibm.com>
Wed, 11 Sep 2013 14:34:04 +0000 (16:34 +0200)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Thu, 24 Oct 2013 15:16:46 +0000 (17:16 +0200)
Same as for bitops: make use of the interlocked-access facility 1
instructions which allow to atomically update storage locations
without a compare-and-swap loop.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
arch/s390/include/asm/atomic.h

index fea2c88..823ec99 100644 (file)
 
 #define ATOMIC_INIT(i)  { (i) }
 
-#define __CS_LOOP(ptr, op_val, op_string) ({                           \
+#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
+
+#define __ATOMIC_OR    "lao"
+#define __ATOMIC_AND   "lan"
+#define __ATOMIC_ADD   "laa"
+
+#define __ATOMIC_LOOP(ptr, op_val, op_string)                          \
+({                                                                     \
+       int old_val;                                                    \
+       asm volatile(                                                   \
+               op_string "     %0,%2,%1\n"                             \
+               : "=d" (old_val), "+Q" (((atomic_t *)(ptr))->counter)   \
+               : "d" (op_val)                                          \
+               : "cc", "memory");                                      \
+       old_val;                                                        \
+})
+
+#else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
+
+#define __ATOMIC_OR    "or"
+#define __ATOMIC_AND   "nr"
+#define __ATOMIC_ADD   "ar"
+
+#define __ATOMIC_LOOP(ptr, op_val, op_string)                          \
+({                                                                     \
        int old_val, new_val;                                           \
        asm volatile(                                                   \
                "       l       %0,%2\n"                                \
                  "=Q" (((atomic_t *)(ptr))->counter)                   \
                : "d" (op_val),  "Q" (((atomic_t *)(ptr))->counter)     \
                : "cc", "memory");                                      \
-       new_val;                                                        \
+       old_val;                                                        \
 })
 
+#endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
+
 static inline int atomic_read(const atomic_t *v)
 {
        int c;
@@ -53,8 +79,9 @@ static inline void atomic_set(atomic_t *v, int i)
 
 static inline int atomic_add_return(int i, atomic_t *v)
 {
-       return __CS_LOOP(v, i, "ar");
+       return __ATOMIC_LOOP(v, i, __ATOMIC_ADD) + i;
 }
+
 #define atomic_add(_i, _v)             atomic_add_return(_i, _v)
 #define atomic_add_negative(_i, _v)    (atomic_add_return(_i, _v) < 0)
 #define atomic_inc(_v)                 atomic_add_return(1, _v)
@@ -69,12 +96,12 @@ static inline int atomic_add_return(int i, atomic_t *v)
 
 static inline void atomic_clear_mask(unsigned long mask, atomic_t *v)
 {
-       __CS_LOOP(v, ~mask, "nr");
+       __ATOMIC_LOOP(v, ~mask, __ATOMIC_AND);
 }
 
 static inline void atomic_set_mask(unsigned long mask, atomic_t *v)
 {
-       __CS_LOOP(v, mask, "or");
+       __ATOMIC_LOOP(v, mask, __ATOMIC_OR);
 }
 
 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
@@ -105,13 +132,37 @@ static inline int __atomic_add_unless(atomic_t *v, int a, int u)
 }
 
 
-#undef __CS_LOOP
+#undef __ATOMIC_LOOP
 
 #define ATOMIC64_INIT(i)  { (i) }
 
 #ifdef CONFIG_64BIT
 
-#define __CSG_LOOP(ptr, op_val, op_string) ({                          \
+#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
+
+#define __ATOMIC64_OR  "laog"
+#define __ATOMIC64_AND "lang"
+#define __ATOMIC64_ADD "laag"
+
+#define __ATOMIC64_LOOP(ptr, op_val, op_string)                                \
+({                                                                     \
+       long long old_val;                                              \
+       asm volatile(                                                   \
+               op_string "     %0,%2,%1\n"                             \
+               : "=d" (old_val), "+Q" (((atomic_t *)(ptr))->counter)   \
+               : "d" (op_val)                                          \
+               : "cc", "memory");                                      \
+       old_val;                                                        \
+})
+
+#else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
+
+#define __ATOMIC64_OR  "ogr"
+#define __ATOMIC64_AND "ngr"
+#define __ATOMIC64_ADD "agr"
+
+#define __ATOMIC64_LOOP(ptr, op_val, op_string)                                \
+({                                                                     \
        long long old_val, new_val;                                     \
        asm volatile(                                                   \
                "       lg      %0,%2\n"                                \
@@ -123,9 +174,11 @@ static inline int __atomic_add_unless(atomic_t *v, int a, int u)
                  "=Q" (((atomic_t *)(ptr))->counter)                   \
                : "d" (op_val), "Q" (((atomic_t *)(ptr))->counter)      \
                : "cc", "memory");                                      \
-       new_val;                                                        \
+       old_val;                                                        \
 })
 
+#endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
+
 static inline long long atomic64_read(const atomic64_t *v)
 {
        long long c;
@@ -145,17 +198,17 @@ static inline void atomic64_set(atomic64_t *v, long long i)
 
 static inline long long atomic64_add_return(long long i, atomic64_t *v)
 {
-       return __CSG_LOOP(v, i, "agr");
+       return __ATOMIC64_LOOP(v, i, __ATOMIC64_ADD) + i;
 }
 
 static inline void atomic64_clear_mask(unsigned long mask, atomic64_t *v)
 {
-       __CSG_LOOP(v, ~mask, "ngr");
+       __ATOMIC64_LOOP(v, ~mask, __ATOMIC64_AND);
 }
 
 static inline void atomic64_set_mask(unsigned long mask, atomic64_t *v)
 {
-       __CSG_LOOP(v, mask, "ogr");
+       __ATOMIC64_LOOP(v, mask, __ATOMIC64_OR);
 }
 
 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
@@ -171,7 +224,7 @@ static inline long long atomic64_cmpxchg(atomic64_t *v,
        return old;
 }
 
-#undef __CSG_LOOP
+#undef __ATOMIC64_LOOP
 
 #else /* CONFIG_64BIT */