diff options
| -rw-r--r-- | arch/arm/include/asm/assembler.h | 13 | ||||
| -rw-r--r-- | arch/arm/include/asm/atomic.h | 61 | ||||
| -rw-r--r-- | arch/arm/include/asm/system.h | 3 | ||||
| -rw-r--r-- | arch/arm/kernel/entry-armv.S | 5 | ||||
| -rw-r--r-- | arch/arm/lib/bitops.h | 2 |
5 files changed, 71 insertions, 13 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index 6116e4893c0..15f8a092b70 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -114,3 +114,16 @@ .align 3; \ .long 9999b,9001f; \ .previous + +/* + * SMP data memory barrier + */ + .macro smp_dmb +#ifdef CONFIG_SMP +#if __LINUX_ARM_ARCH__ >= 7 + dmb +#elif __LINUX_ARM_ARCH__ == 6 + mcr p15, 0, r0, c7, c10, 5 @ dmb +#endif +#endif + .endm diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h index ee99723b3a6..16b52f39798 100644 --- a/arch/arm/include/asm/atomic.h +++ b/arch/arm/include/asm/atomic.h @@ -44,11 +44,29 @@ static inline void atomic_set(atomic_t *v, int i) : "cc"); } +static inline void atomic_add(int i, atomic_t *v) +{ + unsigned long tmp; + int result; + + __asm__ __volatile__("@ atomic_add\n" +"1: ldrex %0, [%2]\n" +" add %0, %0, %3\n" +" strex %1, %0, [%2]\n" +" teq %1, #0\n" +" bne 1b" + : "=&r" (result), "=&r" (tmp) + : "r" (&v->counter), "Ir" (i) + : "cc"); +} + static inline int atomic_add_return(int i, atomic_t *v) { unsigned long tmp; int result; + smp_mb(); + __asm__ __volatile__("@ atomic_add_return\n" "1: ldrex %0, [%2]\n" " add %0, %0, %3\n" @@ -59,14 +77,34 @@ static inline int atomic_add_return(int i, atomic_t *v) : "r" (&v->counter), "Ir" (i) : "cc"); + smp_mb(); + return result; } +static inline void atomic_sub(int i, atomic_t *v) +{ + unsigned long tmp; + int result; + + __asm__ __volatile__("@ atomic_sub\n" +"1: ldrex %0, [%2]\n" +" sub %0, %0, %3\n" +" strex %1, %0, [%2]\n" +" teq %1, #0\n" +" bne 1b" + : "=&r" (result), "=&r" (tmp) + : "r" (&v->counter), "Ir" (i) + : "cc"); +} + static inline int atomic_sub_return(int i, atomic_t *v) { unsigned long tmp; int result; + smp_mb(); + __asm__ __volatile__("@ atomic_sub_return\n" "1: ldrex %0, [%2]\n" " sub %0, %0, %3\n" @@ -77,6 +115,8 @@ static inline int atomic_sub_return(int i, atomic_t *v) : "r" (&v->counter), "Ir" (i) : "cc"); + smp_mb(); + return result; } @@ -84,6 +124,8 @@ static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new) { unsigned long oldval, res; + smp_mb(); + do { __asm__ __volatile__("@ atomic_cmpxchg\n" "ldrex %1, [%2]\n" @@ -95,6 +137,8 @@ static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new) : "cc"); } while (res); + smp_mb(); + return oldval; } @@ -135,6 +179,7 @@ static inline int atomic_add_return(int i, atomic_t *v) return val; } +#define atomic_add(i, v) (void) atomic_add_return(i, v) static inline int atomic_sub_return(int i, atomic_t *v) { @@ -148,6 +193,7 @@ static inline int atomic_sub_return(int i, atomic_t *v) return val; } +#define atomic_sub(i, v) (void) atomic_sub_return(i, v) static inline int atomic_cmpxchg(atomic_t *v, int old, int new) { @@ -187,10 +233,8 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u) } #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) -#define atomic_add(i, v) (void) atomic_add_return(i, v) -#define atomic_inc(v) (void) atomic_add_return(1, v) -#define atomic_sub(i, v) (void) atomic_sub_return(i, v) -#define atomic_dec(v) (void) atomic_sub_return(1, v) +#define atomic_inc(v) atomic_add(1, v) +#define atomic_dec(v) atomic_sub(1, v) #define atomic_inc_and_test(v) (atomic_add_return(1, v) == 0) #define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0) @@ -200,11 +244,10 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u) #define atomic_add_negative(i,v) (atomic_add_return(i, v) < 0) -/* Atomic operations are already serializing on ARM */ -#define smp_mb__before_atomic_dec() barrier() -#define smp_mb__after_atomic_dec() barrier() -#define smp_mb__before_atomic_inc() barrier() -#define smp_mb__after_atomic_inc() barrier() +#define smp_mb__before_atomic_dec() smp_mb() +#define smp_mb__after_atomic_dec() smp_mb() +#define smp_mb__before_atomic_inc() smp_mb() +#define smp_mb__after_atomic_inc() smp_mb() #include <asm-generic/atomic.h> #endif diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h index bd4dc8ed53d..7fce8f3b391 100644 --- a/arch/arm/include/asm/system.h +++ b/arch/arm/include/asm/system.h @@ -248,6 +248,8 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size unsigned int tmp; #endif + smp_mb(); + switch (size) { #if __LINUX_ARM_ARCH__ >= 6 case 1: @@ -307,6 +309,7 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size __bad_xchg(ptr, size), ret = 0; break; } + smp_mb(); return ret; } diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index d662a2f1fd8..83b1da6b7ba 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -815,10 +815,7 @@ __kuser_helper_start: */ __kuser_memory_barrier: @ 0xffff0fa0 - -#if __LINUX_ARM_ARCH__ >= 6 && defined(CONFIG_SMP) - mcr p15, 0, r0, c7, c10, 5 @ dmb -#endif + smp_dmb usr_ret lr .align 5 diff --git a/arch/arm/lib/bitops.h b/arch/arm/lib/bitops.h index 2e787d40d59..c7f2627385e 100644 --- a/arch/arm/lib/bitops.h +++ b/arch/arm/lib/bitops.h @@ -18,12 +18,14 @@ mov r2, #1 add r1, r1, r0, lsr #3 @ Get byte offset mov r3, r2, lsl r3 @ create mask + smp_dmb 1: ldrexb r2, [r1] ands r0, r2, r3 @ save old value of bit \instr r2, r2, r3 @ toggle bit strexb ip, r2, [r1] cmp ip, #0 bne 1b + smp_dmb cmp r0, #0 movne r0, #1 2: mov pc, lr |