diff options
author | Peter Zijlstra <peterz@infradead.org> | 2016-04-17 23:16:04 (GMT) |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-06-16 08:48:29 (GMT) |
commit | 7d9794e7523798e1b9422ad9f4e4d808ae5d5932 (patch) | |
tree | 3a1a550803485049b8e8c2a434c0c9107831f3a6 /arch | |
parent | 56fefbbc3f13ad8cc9f502dbc6b5c9ddc8c4395e (diff) | |
download | linux-7d9794e7523798e1b9422ad9f4e4d808ae5d5932.tar.xz |
locking/atomic, arch/sh: Implement atomic_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) <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: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/sh/include/asm/atomic-grb.h | 34 | ||||
-rw-r--r-- | arch/sh/include/asm/atomic-irq.h | 31 | ||||
-rw-r--r-- | arch/sh/include/asm/atomic-llsc.h | 32 | ||||
-rw-r--r-- | arch/sh/include/asm/atomic.h | 2 |
4 files changed, 87 insertions, 12 deletions
diff --git a/arch/sh/include/asm/atomic-grb.h b/arch/sh/include/asm/atomic-grb.h index b94df40..d755e96 100644 --- a/arch/sh/include/asm/atomic-grb.h +++ b/arch/sh/include/asm/atomic-grb.h @@ -43,16 +43,42 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \ return tmp; \ } -#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) +#define ATOMIC_FETCH_OP(op) \ +static inline int atomic_fetch_##op(int i, atomic_t *v) \ +{ \ + int res, tmp; \ + \ + __asm__ __volatile__ ( \ + " .align 2 \n\t" \ + " mova 1f, r0 \n\t" /* r0 = end point */ \ + " mov r15, r1 \n\t" /* r1 = saved sp */ \ + " mov #-6, r15 \n\t" /* LOGIN: r15 = size */ \ + " mov.l @%2, %0 \n\t" /* load old value */ \ + " mov %0, %1 \n\t" /* save old value */ \ + " " #op " %3, %0 \n\t" /* $op */ \ + " mov.l %0, @%2 \n\t" /* store new value */ \ + "1: mov r1, r15 \n\t" /* LOGOUT */ \ + : "=&r" (tmp), "=&r" (res), "+r" (v) \ + : "r" (i) \ + : "memory" , "r0", "r1"); \ + \ + return res; \ +} + +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op) ATOMIC_OPS(add) ATOMIC_OPS(sub) -ATOMIC_OP(and) -ATOMIC_OP(or) -ATOMIC_OP(xor) +#undef ATOMIC_OPS +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) + +ATOMIC_OPS(and) +ATOMIC_OPS(or) +ATOMIC_OPS(xor) #undef ATOMIC_OPS +#undef ATOMIC_FETCH_OP #undef ATOMIC_OP_RETURN #undef ATOMIC_OP diff --git a/arch/sh/include/asm/atomic-irq.h b/arch/sh/include/asm/atomic-irq.h index 23fcdad..8e2da5f 100644 --- a/arch/sh/include/asm/atomic-irq.h +++ b/arch/sh/include/asm/atomic-irq.h @@ -33,15 +33,38 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \ return temp; \ } -#define ATOMIC_OPS(op, c_op) ATOMIC_OP(op, c_op) ATOMIC_OP_RETURN(op, c_op) +#define ATOMIC_FETCH_OP(op, c_op) \ +static inline int atomic_fetch_##op(int i, atomic_t *v) \ +{ \ + unsigned long temp, flags; \ + \ + raw_local_irq_save(flags); \ + temp = v->counter; \ + v->counter c_op i; \ + raw_local_irq_restore(flags); \ + \ + return temp; \ +} + +#define ATOMIC_OPS(op, c_op) \ + ATOMIC_OP(op, c_op) \ + ATOMIC_OP_RETURN(op, c_op) \ + ATOMIC_FETCH_OP(op, c_op) ATOMIC_OPS(add, +=) ATOMIC_OPS(sub, -=) -ATOMIC_OP(and, &=) -ATOMIC_OP(or, |=) -ATOMIC_OP(xor, ^=) #undef ATOMIC_OPS +#define ATOMIC_OPS(op, c_op) \ + ATOMIC_OP(op, c_op) \ + ATOMIC_FETCH_OP(op, c_op) + +ATOMIC_OPS(and, &=) +ATOMIC_OPS(or, |=) +ATOMIC_OPS(xor, ^=) + +#undef ATOMIC_OPS +#undef ATOMIC_FETCH_OP #undef ATOMIC_OP_RETURN #undef ATOMIC_OP diff --git a/arch/sh/include/asm/atomic-llsc.h b/arch/sh/include/asm/atomic-llsc.h index 33d34b1..caea2c4 100644 --- a/arch/sh/include/asm/atomic-llsc.h +++ b/arch/sh/include/asm/atomic-llsc.h @@ -48,15 +48,39 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \ return temp; \ } -#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) +#define ATOMIC_FETCH_OP(op) \ +static inline int atomic_fetch_##op(int i, atomic_t *v) \ +{ \ + unsigned long res, temp; \ + \ + __asm__ __volatile__ ( \ +"1: movli.l @%3, %0 ! atomic_fetch_" #op " \n" \ +" mov %0, %1 \n" \ +" " #op " %2, %0 \n" \ +" movco.l %0, @%3 \n" \ +" bf 1b \n" \ +" synco \n" \ + : "=&z" (temp), "=&z" (res) \ + : "r" (i), "r" (&v->counter) \ + : "t"); \ + \ + return res; \ +} + +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op) ATOMIC_OPS(add) ATOMIC_OPS(sub) -ATOMIC_OP(and) -ATOMIC_OP(or) -ATOMIC_OP(xor) #undef ATOMIC_OPS +#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) + +ATOMIC_OPS(and) +ATOMIC_OPS(or) +ATOMIC_OPS(xor) + +#undef ATOMIC_OPS +#undef ATOMIC_FETCH_OP #undef ATOMIC_OP_RETURN #undef ATOMIC_OP diff --git a/arch/sh/include/asm/atomic.h b/arch/sh/include/asm/atomic.h index c399e1c..d93ed7c 100644 --- a/arch/sh/include/asm/atomic.h +++ b/arch/sh/include/asm/atomic.h @@ -25,6 +25,8 @@ #include <asm/atomic-irq.h> #endif +#define atomic_fetch_or atomic_fetch_or + #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) #define atomic_dec_return(v) atomic_sub_return(1, (v)) #define atomic_inc_return(v) atomic_add_return(1, (v)) |