From d839bae4269aea46bff4133066a411cfba5c7c46 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra <peterz@infradead.org> Date: Sun, 23 Mar 2014 19:06:34 +0100 Subject: locking,arch,m68k: Fold atomic_ops Many of the atomic op implementations are the same except for one instruction; fold the lot into a few CPP macros and reduce LoC. This also prepares for easy addition of new ops. Requires asm_op due to eor. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: linux-m68k@lists.linux-m68k.org Link: http://lkml.kernel.org/r/20140509091646.GO30445@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> --- arch/m68k/include/asm/atomic.h | 109 ++++++++++++++++++----------------------- 1 file changed, 47 insertions(+), 62 deletions(-) (limited to 'arch/m68k') diff --git a/arch/m68k/include/asm/atomic.h b/arch/m68k/include/asm/atomic.h index 55695212a2ae..663d4ba2462c 100644 --- a/arch/m68k/include/asm/atomic.h +++ b/arch/m68k/include/asm/atomic.h @@ -30,16 +30,57 @@ #define ASM_DI "di" #endif -static inline void atomic_add(int i, atomic_t *v) -{ - __asm__ __volatile__("addl %1,%0" : "+m" (*v) : ASM_DI (i)); +#define ATOMIC_OP(op, c_op, asm_op) \ +static inline void atomic_##op(int i, atomic_t *v) \ +{ \ + __asm__ __volatile__(#asm_op "l %1,%0" : "+m" (*v) : ASM_DI (i));\ +} \ + +#ifdef CONFIG_RMW_INSNS + +#define ATOMIC_OP_RETURN(op, c_op, asm_op) \ +static inline int atomic_##op##_return(int i, atomic_t *v) \ +{ \ + int t, tmp; \ + \ + __asm__ __volatile__( \ + "1: movel %2,%1\n" \ + " " #asm_op "l %3,%1\n" \ + " casl %2,%1,%0\n" \ + " jne 1b" \ + : "+m" (*v), "=&d" (t), "=&d" (tmp) \ + : "g" (i), "2" (atomic_read(v))); \ + return t; \ } -static inline void atomic_sub(int i, atomic_t *v) -{ - __asm__ __volatile__("subl %1,%0" : "+m" (*v) : ASM_DI (i)); +#else + +#define ATOMIC_OP_RETURN(op, c_op, asm_op) \ +static inline int atomic_##op##_return(int i, atomic_t * v) \ +{ \ + unsigned long flags; \ + int t; \ + \ + local_irq_save(flags); \ + t = (v->counter c_op i); \ + local_irq_restore(flags); \ + \ + return t; \ } +#endif /* CONFIG_RMW_INSNS */ + +#define ATOMIC_OPS(op, c_op, asm_op) \ + ATOMIC_OP(op, c_op, asm_op) \ + ATOMIC_OP_RETURN(op, c_op, asm_op) + +ATOMIC_OPS(add, +=, add) +ATOMIC_OPS(sub, -=, sub) + +#undef ATOMIC_OPS +#undef ATOMIC_OP_RETURN +#undef ATOMIC_OP + static inline void atomic_inc(atomic_t *v) { __asm__ __volatile__("addql #1,%0" : "+m" (*v)); @@ -76,67 +117,11 @@ static inline int atomic_inc_and_test(atomic_t *v) #ifdef CONFIG_RMW_INSNS -static inline int atomic_add_return(int i, atomic_t *v) -{ - int t, tmp; - - __asm__ __volatile__( - "1: movel %2,%1\n" - " addl %3,%1\n" - " casl %2,%1,%0\n" - " jne 1b" - : "+m" (*v), "=&d" (t), "=&d" (tmp) - : "g" (i), "2" (atomic_read(v))); - return t; -} - -static inline int atomic_sub_return(int i, atomic_t *v) -{ - int t, tmp; - - __asm__ __volatile__( - "1: movel %2,%1\n" - " subl %3,%1\n" - " casl %2,%1,%0\n" - " jne 1b" - : "+m" (*v), "=&d" (t), "=&d" (tmp) - : "g" (i), "2" (atomic_read(v))); - return t; -} - #define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n))) #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) #else /* !CONFIG_RMW_INSNS */ -static inline int atomic_add_return(int i, atomic_t * v) -{ - unsigned long flags; - int t; - - local_irq_save(flags); - t = atomic_read(v); - t += i; - atomic_set(v, t); - local_irq_restore(flags); - - return t; -} - -static inline int atomic_sub_return(int i, atomic_t * v) -{ - unsigned long flags; - int t; - - local_irq_save(flags); - t = atomic_read(v); - t -= i; - atomic_set(v, t); - local_irq_restore(flags); - - return t; -} - static inline int atomic_cmpxchg(atomic_t *v, int old, int new) { unsigned long flags; -- cgit v1.2.2 From 2291059c852706c6f5ffb400366042b7625066cd Mon Sep 17 00:00:00 2001 From: Pranith Kumar <bobby.prani@gmail.com> Date: Tue, 23 Sep 2014 10:29:50 -0400 Subject: locking,arch: Use ACCESS_ONCE() instead of cast to volatile in atomic_read() Use the much more reader friendly ACCESS_ONCE() instead of the cast to volatile. This is purely a stylistic change. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/1411482607-20948-1-git-send-email-bobby.prani@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> --- arch/m68k/include/asm/atomic.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/m68k') diff --git a/arch/m68k/include/asm/atomic.h b/arch/m68k/include/asm/atomic.h index 663d4ba2462c..e85f047fb072 100644 --- a/arch/m68k/include/asm/atomic.h +++ b/arch/m68k/include/asm/atomic.h @@ -17,7 +17,7 @@ #define ATOMIC_INIT(i) { (i) } -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v, i) (((v)->counter) = i) /* -- cgit v1.2.2