[PATCH] s390: atomic primitives
Hugh Dickins <hugh@veritas.com>
Fix the broken atomic_cmpxchg primitive. Add atomic_sub_and_test,
atomic64_sub_return, atomic64_sub_and_test, atomic64_cmpxchg,
atomic64_add_unless and atomic64_inc_not_zero. Replace old style
atomic_compare_and_swap by atomic_cmpxchg. Shorten the whole header by
defining most primitives with the two inline functions atomic_add_return and
atomic_sub_return.
In addition this patch contains the s390 related fixes of Hugh's "mm: fill
arch atomic64 gaps" patch.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/asm-s390/atomic.h b/include/asm-s390/atomic.h
index 6d07c7d..d82aedf 100644
--- a/include/asm-s390/atomic.h
+++ b/include/asm-s390/atomic.h
@@ -5,7 +5,7 @@
* include/asm-s390/atomic.h
*
* S390 version
- * Copyright (C) 1999-2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Copyright (C) 1999-2005 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
* Denis Joseph Barrow,
* Arnd Bergmann (arndb@de.ibm.com)
@@ -45,59 +45,57 @@
#define atomic_read(v) ((v)->counter)
#define atomic_set(v,i) (((v)->counter) = (i))
-static __inline__ void atomic_add(int i, atomic_t * v)
-{
- __CS_LOOP(v, i, "ar");
-}
static __inline__ int atomic_add_return(int i, atomic_t * v)
{
return __CS_LOOP(v, i, "ar");
}
-static __inline__ int atomic_add_negative(int i, atomic_t * v)
-{
- return __CS_LOOP(v, i, "ar") < 0;
-}
-static __inline__ void atomic_sub(int i, atomic_t * v)
-{
- __CS_LOOP(v, i, "sr");
-}
+#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)
+#define atomic_inc_return(_v) atomic_add_return(1, _v)
+#define atomic_inc_and_test(_v) (atomic_add_return(1, _v) == 0)
+
static __inline__ int atomic_sub_return(int i, atomic_t * v)
{
return __CS_LOOP(v, i, "sr");
}
-static __inline__ void atomic_inc(volatile atomic_t * v)
-{
- __CS_LOOP(v, 1, "ar");
-}
-static __inline__ int atomic_inc_return(volatile atomic_t * v)
-{
- return __CS_LOOP(v, 1, "ar");
-}
+#define atomic_sub(_i, _v) atomic_sub_return(_i, _v)
+#define atomic_sub_and_test(_i, _v) (atomic_sub_return(_i, _v) == 0)
+#define atomic_dec(_v) atomic_sub_return(1, _v)
+#define atomic_dec_return(_v) atomic_sub_return(1, _v)
+#define atomic_dec_and_test(_v) (atomic_sub_return(1, _v) == 0)
-static __inline__ int atomic_inc_and_test(volatile atomic_t * v)
-{
- return __CS_LOOP(v, 1, "ar") == 0;
-}
-static __inline__ void atomic_dec(volatile atomic_t * v)
-{
- __CS_LOOP(v, 1, "sr");
-}
-static __inline__ int atomic_dec_return(volatile atomic_t * v)
-{
- return __CS_LOOP(v, 1, "sr");
-}
-static __inline__ int atomic_dec_and_test(volatile atomic_t * v)
-{
- return __CS_LOOP(v, 1, "sr") == 0;
-}
static __inline__ void atomic_clear_mask(unsigned long mask, atomic_t * v)
{
__CS_LOOP(v, ~mask, "nr");
}
+
static __inline__ void atomic_set_mask(unsigned long mask, atomic_t * v)
{
__CS_LOOP(v, mask, "or");
}
+
+static __inline__ int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ __asm__ __volatile__(" cs %0,%3,0(%2)\n"
+ : "+d" (old), "=m" (v->counter)
+ : "a" (v), "d" (new), "m" (v->counter)
+ : "cc", "memory" );
+ return old;
+}
+
+static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int c, old;
+
+ c = atomic_read(v);
+ while (c != u && (old = atomic_cmpxchg(v, c, c + a)) != c)
+ c = old;
+ return c != u;
+}
+
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
#undef __CS_LOOP
#ifdef __s390x__
@@ -123,92 +121,61 @@
#define atomic64_read(v) ((v)->counter)
#define atomic64_set(v,i) (((v)->counter) = (i))
-static __inline__ void atomic64_add(long long i, atomic64_t * v)
-{
- __CSG_LOOP(v, i, "agr");
-}
static __inline__ long long atomic64_add_return(long long i, atomic64_t * v)
{
return __CSG_LOOP(v, i, "agr");
}
-static __inline__ long long atomic64_add_negative(long long i, atomic64_t * v)
+#define atomic64_add(_i, _v) atomic64_add_return(_i, _v)
+#define atomic64_add_negative(_i, _v) (atomic64_add_return(_i, _v) < 0)
+#define atomic64_inc(_v) atomic64_add_return(1, _v)
+#define atomic64_inc_return(_v) atomic64_add_return(1, _v)
+#define atomic64_inc_and_test(_v) (atomic64_add_return(1, _v) == 0)
+
+static __inline__ long long atomic64_sub_return(long long i, atomic64_t * v)
{
- return __CSG_LOOP(v, i, "agr") < 0;
+ return __CSG_LOOP(v, i, "sgr");
}
-static __inline__ void atomic64_sub(long long i, atomic64_t * v)
-{
- __CSG_LOOP(v, i, "sgr");
-}
-static __inline__ void atomic64_inc(volatile atomic64_t * v)
-{
- __CSG_LOOP(v, 1, "agr");
-}
-static __inline__ long long atomic64_inc_return(volatile atomic64_t * v)
-{
- return __CSG_LOOP(v, 1, "agr");
-}
-static __inline__ long long atomic64_inc_and_test(volatile atomic64_t * v)
-{
- return __CSG_LOOP(v, 1, "agr") == 0;
-}
-static __inline__ void atomic64_dec(volatile atomic64_t * v)
-{
- __CSG_LOOP(v, 1, "sgr");
-}
-static __inline__ long long atomic64_dec_return(volatile atomic64_t * v)
-{
- return __CSG_LOOP(v, 1, "sgr");
-}
-static __inline__ long long atomic64_dec_and_test(volatile atomic64_t * v)
-{
- return __CSG_LOOP(v, 1, "sgr") == 0;
-}
+#define atomic64_sub(_i, _v) atomic64_sub_return(_i, _v)
+#define atomic64_sub_and_test(_i, _v) (atomic64_sub_return(_i, _v) == 0)
+#define atomic64_dec(_v) atomic64_sub_return(1, _v)
+#define atomic64_dec_return(_v) atomic64_sub_return(1, _v)
+#define atomic64_dec_and_test(_v) (atomic64_sub_return(1, _v) == 0)
+
static __inline__ void atomic64_clear_mask(unsigned long mask, atomic64_t * v)
{
__CSG_LOOP(v, ~mask, "ngr");
}
+
static __inline__ void atomic64_set_mask(unsigned long mask, atomic64_t * v)
{
__CSG_LOOP(v, mask, "ogr");
}
-#undef __CSG_LOOP
-#endif
-
-/*
- returns 0 if expected_oldval==value in *v ( swap was successful )
- returns 1 if unsuccessful.
-
- This is non-portable, use bitops or spinlocks instead!
-*/
-static __inline__ int
-atomic_compare_and_swap(int expected_oldval,int new_val,atomic_t *v)
+static __inline__ long long atomic64_cmpxchg(atomic64_t *v,
+ long long old, long long new)
{
- int retval;
-
- __asm__ __volatile__(
- " lr %0,%3\n"
- " cs %0,%4,0(%2)\n"
- " ipm %0\n"
- " srl %0,28\n"
- "0:"
- : "=&d" (retval), "=m" (v->counter)
- : "a" (v), "d" (expected_oldval) , "d" (new_val),
- "m" (v->counter) : "cc", "memory" );
- return retval;
+ __asm__ __volatile__(" csg %0,%3,0(%2)\n"
+ : "+d" (old), "=m" (v->counter)
+ : "a" (v), "d" (new), "m" (v->counter)
+ : "cc", "memory" );
+ return old;
}
-#define atomic_cmpxchg(v, o, n) (atomic_compare_and_swap((o), (n), &((v)->counter)))
+static __inline__ int atomic64_add_unless(atomic64_t *v,
+ long long a, long long u)
+{
+ long long c, old;
-#define atomic_add_unless(v, a, u) \
-({ \
- int c, old; \
- c = atomic_read(v); \
- while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
- c = old; \
- c != (u); \
-})
-#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+ c = atomic64_read(v);
+ while (c != u && (old = atomic64_cmpxchg(v, c, c + a)) != c)
+ c = old;
+ return c != u;
+}
+
+#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
+
+#undef __CSG_LOOP
+#endif
#define smp_mb__before_atomic_dec() smp_mb()
#define smp_mb__after_atomic_dec() smp_mb()