From cc102507fac75f9f4f37938f49d10c25e596a608 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 18 Apr 2016 01:16:07 +0200 Subject: [PATCH] locking/atomic, arch/ia64: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() Implement FETCH-OP atomic primitives, these are very similar to the existing OP-RETURN primitives we already have, except they return the value of the atomic variable _before_ modification. This is especially useful for irreversible operations -- such as bitops (because it becomes impossible to reconstruct the state prior to modification). Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Fenghua Yu Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Tony Luck Cc: linux-arch@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- arch/ia64/include/asm/atomic.h | 130 +++++++++++++++++++++++++++++---- 1 file changed, 114 insertions(+), 16 deletions(-) diff --git a/arch/ia64/include/asm/atomic.h b/arch/ia64/include/asm/atomic.h index 8dfb5f6f6c35..f565ad376142 100644 --- a/arch/ia64/include/asm/atomic.h +++ b/arch/ia64/include/asm/atomic.h @@ -42,8 +42,27 @@ ia64_atomic_##op (int i, atomic_t *v) \ return new; \ } -ATOMIC_OP(add, +) -ATOMIC_OP(sub, -) +#define ATOMIC_FETCH_OP(op, c_op) \ +static __inline__ int \ +ia64_atomic_fetch_##op (int i, atomic_t *v) \ +{ \ + __s32 old, new; \ + CMPXCHG_BUGCHECK_DECL \ + \ + do { \ + CMPXCHG_BUGCHECK(v); \ + old = atomic_read(v); \ + new = old c_op i; \ + } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old); \ + return old; \ +} + +#define ATOMIC_OPS(op, c_op) \ + ATOMIC_OP(op, c_op) \ + ATOMIC_FETCH_OP(op, c_op) + +ATOMIC_OPS(add, +) +ATOMIC_OPS(sub, -) #define atomic_add_return(i,v) \ ({ \ @@ -69,14 +88,44 @@ ATOMIC_OP(sub, -) : ia64_atomic_sub(__ia64_asr_i, v); \ }) -ATOMIC_OP(and, &) -ATOMIC_OP(or, |) -ATOMIC_OP(xor, ^) +#define atomic_fetch_add(i,v) \ +({ \ + int __ia64_aar_i = (i); \ + (__builtin_constant_p(i) \ + && ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \ + || (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \ + || (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \ + || (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \ + ? ia64_fetchadd(__ia64_aar_i, &(v)->counter, acq) \ + : ia64_atomic_fetch_add(__ia64_aar_i, v); \ +}) + +#define atomic_fetch_sub(i,v) \ +({ \ + int __ia64_asr_i = (i); \ + (__builtin_constant_p(i) \ + && ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \ + || (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \ + || (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \ + || (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \ + ? ia64_fetchadd(-__ia64_asr_i, &(v)->counter, acq) \ + : ia64_atomic_fetch_sub(__ia64_asr_i, v); \ +}) + +ATOMIC_FETCH_OP(and, &) +ATOMIC_FETCH_OP(or, |) +ATOMIC_FETCH_OP(xor, ^) + +#define atomic_and(i,v) (void)ia64_atomic_fetch_and(i,v) +#define atomic_or(i,v) (void)ia64_atomic_fetch_or(i,v) +#define atomic_xor(i,v) (void)ia64_atomic_fetch_xor(i,v) -#define atomic_and(i,v) (void)ia64_atomic_and(i,v) -#define atomic_or(i,v) (void)ia64_atomic_or(i,v) -#define atomic_xor(i,v) (void)ia64_atomic_xor(i,v) +#define atomic_fetch_and(i,v) ia64_atomic_fetch_and(i,v) +#define atomic_fetch_or(i,v) ia64_atomic_fetch_or(i,v) +#define atomic_fetch_xor(i,v) ia64_atomic_fetch_xor(i,v) +#undef ATOMIC_OPS +#undef ATOMIC_FETCH_OP #undef ATOMIC_OP #define ATOMIC64_OP(op, c_op) \ @@ -94,8 +143,27 @@ ia64_atomic64_##op (__s64 i, atomic64_t *v) \ return new; \ } -ATOMIC64_OP(add, +) -ATOMIC64_OP(sub, -) +#define ATOMIC64_FETCH_OP(op, c_op) \ +static __inline__ long \ +ia64_atomic64_fetch_##op (__s64 i, atomic64_t *v) \ +{ \ + __s64 old, new; \ + CMPXCHG_BUGCHECK_DECL \ + \ + do { \ + CMPXCHG_BUGCHECK(v); \ + old = atomic64_read(v); \ + new = old c_op i; \ + } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old); \ + return old; \ +} + +#define ATOMIC64_OPS(op, c_op) \ + ATOMIC64_OP(op, c_op) \ + ATOMIC64_FETCH_OP(op, c_op) + +ATOMIC64_OPS(add, +) +ATOMIC64_OPS(sub, -) #define atomic64_add_return(i,v) \ ({ \ @@ -121,14 +189,44 @@ ATOMIC64_OP(sub, -) : ia64_atomic64_sub(__ia64_asr_i, v); \ }) -ATOMIC64_OP(and, &) -ATOMIC64_OP(or, |) -ATOMIC64_OP(xor, ^) +#define atomic64_fetch_add(i,v) \ +({ \ + long __ia64_aar_i = (i); \ + (__builtin_constant_p(i) \ + && ( (__ia64_aar_i == 1) || (__ia64_aar_i == 4) \ + || (__ia64_aar_i == 8) || (__ia64_aar_i == 16) \ + || (__ia64_aar_i == -1) || (__ia64_aar_i == -4) \ + || (__ia64_aar_i == -8) || (__ia64_aar_i == -16))) \ + ? ia64_fetchadd(__ia64_aar_i, &(v)->counter, acq) \ + : ia64_atomic64_fetch_add(__ia64_aar_i, v); \ +}) + +#define atomic64_fetch_sub(i,v) \ +({ \ + long __ia64_asr_i = (i); \ + (__builtin_constant_p(i) \ + && ( (__ia64_asr_i == 1) || (__ia64_asr_i == 4) \ + || (__ia64_asr_i == 8) || (__ia64_asr_i == 16) \ + || (__ia64_asr_i == -1) || (__ia64_asr_i == -4) \ + || (__ia64_asr_i == -8) || (__ia64_asr_i == -16))) \ + ? ia64_fetchadd(-__ia64_asr_i, &(v)->counter, acq) \ + : ia64_atomic64_fetch_sub(__ia64_asr_i, v); \ +}) + +ATOMIC64_FETCH_OP(and, &) +ATOMIC64_FETCH_OP(or, |) +ATOMIC64_FETCH_OP(xor, ^) + +#define atomic64_and(i,v) (void)ia64_atomic64_fetch_and(i,v) +#define atomic64_or(i,v) (void)ia64_atomic64_fetch_or(i,v) +#define atomic64_xor(i,v) (void)ia64_atomic64_fetch_xor(i,v) -#define atomic64_and(i,v) (void)ia64_atomic64_and(i,v) -#define atomic64_or(i,v) (void)ia64_atomic64_or(i,v) -#define atomic64_xor(i,v) (void)ia64_atomic64_xor(i,v) +#define atomic64_fetch_and(i,v) ia64_atomic64_fetch_and(i,v) +#define atomic64_fetch_or(i,v) ia64_atomic64_fetch_or(i,v) +#define atomic64_fetch_xor(i,v) ia64_atomic64_fetch_xor(i,v) +#undef ATOMIC64_OPS +#undef ATOMIC64_FETCH_OP #undef ATOMIC64_OP #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new)) -- 2.20.1