diff options
Diffstat (limited to 'arch/alpha/include/asm/cmpxchg.h')
| -rw-r--r-- | arch/alpha/include/asm/cmpxchg.h | 239 |
1 files changed, 223 insertions, 16 deletions
diff --git a/arch/alpha/include/asm/cmpxchg.h b/arch/alpha/include/asm/cmpxchg.h index 91d4a4d9258c..ae1b96479d0c 100644 --- a/arch/alpha/include/asm/cmpxchg.h +++ b/arch/alpha/include/asm/cmpxchg.h @@ -3,17 +3,232 @@ #define _ALPHA_CMPXCHG_H /* - * Atomic exchange routines. + * Atomic exchange. + * Since it can be used to implement critical sections + * it must clobber "memory" (also for interrupts in UP). */ -#define ____xchg(type, args...) __arch_xchg ## type ## _local(args) -#define ____cmpxchg(type, args...) __cmpxchg ## type ## _local(args) -#include <asm/xchg.h> +static inline unsigned long +____xchg_u8(volatile char *m, unsigned long val) +{ + unsigned long ret, tmp, addr64; + + __asm__ __volatile__( + " andnot %4,7,%3\n" + " insbl %1,%4,%1\n" + "1: ldq_l %2,0(%3)\n" + " extbl %2,%4,%0\n" + " mskbl %2,%4,%2\n" + " or %1,%2,%2\n" + " stq_c %2,0(%3)\n" + " beq %2,2f\n" + ".subsection 2\n" + "2: br 1b\n" + ".previous" + : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64) + : "r" ((long)m), "1" (val) : "memory"); + + return ret; +} + +static inline unsigned long +____xchg_u16(volatile short *m, unsigned long val) +{ + unsigned long ret, tmp, addr64; + + __asm__ __volatile__( + " andnot %4,7,%3\n" + " inswl %1,%4,%1\n" + "1: ldq_l %2,0(%3)\n" + " extwl %2,%4,%0\n" + " mskwl %2,%4,%2\n" + " or %1,%2,%2\n" + " stq_c %2,0(%3)\n" + " beq %2,2f\n" + ".subsection 2\n" + "2: br 1b\n" + ".previous" + : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64) + : "r" ((long)m), "1" (val) : "memory"); + + return ret; +} + +static inline unsigned long +____xchg_u32(volatile int *m, unsigned long val) +{ + unsigned long dummy; + + __asm__ __volatile__( + "1: ldl_l %0,%4\n" + " bis $31,%3,%1\n" + " stl_c %1,%2\n" + " beq %1,2f\n" + ".subsection 2\n" + "2: br 1b\n" + ".previous" + : "=&r" (val), "=&r" (dummy), "=m" (*m) + : "rI" (val), "m" (*m) : "memory"); + + return val; +} + +static inline unsigned long +____xchg_u64(volatile long *m, unsigned long val) +{ + unsigned long dummy; + + __asm__ __volatile__( + "1: ldq_l %0,%4\n" + " bis $31,%3,%1\n" + " stq_c %1,%2\n" + " beq %1,2f\n" + ".subsection 2\n" + "2: br 1b\n" + ".previous" + : "=&r" (val), "=&r" (dummy), "=m" (*m) + : "rI" (val), "m" (*m) : "memory"); + + return val; +} + +/* This function doesn't exist, so you'll get a linker error + if something tries to do an invalid xchg(). */ +extern void __xchg_called_with_bad_pointer(void); + +static __always_inline unsigned long +____xchg(volatile void *ptr, unsigned long x, int size) +{ + return + size == 1 ? ____xchg_u8(ptr, x) : + size == 2 ? ____xchg_u16(ptr, x) : + size == 4 ? ____xchg_u32(ptr, x) : + size == 8 ? ____xchg_u64(ptr, x) : + (__xchg_called_with_bad_pointer(), x); +} + +/* + * Atomic compare and exchange. Compare OLD with MEM, if identical, + * store NEW in MEM. Return the initial value in MEM. Success is + * indicated by comparing RETURN with OLD. + */ + +static inline unsigned long +____cmpxchg_u8(volatile char *m, unsigned char old, unsigned char new) +{ + unsigned long prev, tmp, cmp, addr64; + + __asm__ __volatile__( + " andnot %5,7,%4\n" + " insbl %1,%5,%1\n" + "1: ldq_l %2,0(%4)\n" + " extbl %2,%5,%0\n" + " cmpeq %0,%6,%3\n" + " beq %3,2f\n" + " mskbl %2,%5,%2\n" + " or %1,%2,%2\n" + " stq_c %2,0(%4)\n" + " beq %2,3f\n" + "2:\n" + ".subsection 2\n" + "3: br 1b\n" + ".previous" + : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64) + : "r" ((long)m), "Ir" (old), "1" (new) : "memory"); + + return prev; +} + +static inline unsigned long +____cmpxchg_u16(volatile short *m, unsigned short old, unsigned short new) +{ + unsigned long prev, tmp, cmp, addr64; + + __asm__ __volatile__( + " andnot %5,7,%4\n" + " inswl %1,%5,%1\n" + "1: ldq_l %2,0(%4)\n" + " extwl %2,%5,%0\n" + " cmpeq %0,%6,%3\n" + " beq %3,2f\n" + " mskwl %2,%5,%2\n" + " or %1,%2,%2\n" + " stq_c %2,0(%4)\n" + " beq %2,3f\n" + "2:\n" + ".subsection 2\n" + "3: br 1b\n" + ".previous" + : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64) + : "r" ((long)m), "Ir" (old), "1" (new) : "memory"); + + return prev; +} + +static inline unsigned long +____cmpxchg_u32(volatile int *m, int old, int new) +{ + unsigned long prev, cmp; + + __asm__ __volatile__( + "1: ldl_l %0,%5\n" + " cmpeq %0,%3,%1\n" + " beq %1,2f\n" + " mov %4,%1\n" + " stl_c %1,%2\n" + " beq %1,3f\n" + "2:\n" + ".subsection 2\n" + "3: br 1b\n" + ".previous" + : "=&r"(prev), "=&r"(cmp), "=m"(*m) + : "r"((long) old), "r"(new), "m"(*m) : "memory"); + + return prev; +} + +static inline unsigned long +____cmpxchg_u64(volatile long *m, unsigned long old, unsigned long new) +{ + unsigned long prev, cmp; + + __asm__ __volatile__( + "1: ldq_l %0,%5\n" + " cmpeq %0,%3,%1\n" + " beq %1,2f\n" + " mov %4,%1\n" + " stq_c %1,%2\n" + " beq %1,3f\n" + "2:\n" + ".subsection 2\n" + "3: br 1b\n" + ".previous" + : "=&r"(prev), "=&r"(cmp), "=m"(*m) + : "r"((long) old), "r"(new), "m"(*m) : "memory"); + + return prev; +} + +/* This function doesn't exist, so you'll get a linker error + if something tries to do an invalid cmpxchg(). */ +extern void __cmpxchg_called_with_bad_pointer(void); + +static __always_inline unsigned long +____cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, + int size) +{ + return + size == 1 ? ____cmpxchg_u8(ptr, old, new) : + size == 2 ? ____cmpxchg_u16(ptr, old, new) : + size == 4 ? ____cmpxchg_u32(ptr, old, new) : + size == 8 ? ____cmpxchg_u64(ptr, old, new) : + (__cmpxchg_called_with_bad_pointer(), old); +} #define xchg_local(ptr, x) \ ({ \ __typeof__(*(ptr)) _x_ = (x); \ - (__typeof__(*(ptr))) __arch_xchg_local((ptr), (unsigned long)_x_,\ + (__typeof__(*(ptr))) ____xchg((ptr), (unsigned long)_x_, \ sizeof(*(ptr))); \ }) @@ -21,7 +236,7 @@ ({ \ __typeof__(*(ptr)) _o_ = (o); \ __typeof__(*(ptr)) _n_ = (n); \ - (__typeof__(*(ptr))) __cmpxchg_local((ptr), (unsigned long)_o_, \ + (__typeof__(*(ptr))) ____cmpxchg((ptr), (unsigned long)_o_, \ (unsigned long)_n_, \ sizeof(*(ptr))); \ }) @@ -32,12 +247,6 @@ cmpxchg_local((ptr), (o), (n)); \ }) -#undef ____xchg -#undef ____cmpxchg -#define ____xchg(type, args...) __arch_xchg ##type(args) -#define ____cmpxchg(type, args...) __cmpxchg ##type(args) -#include <asm/xchg.h> - /* * The leading and the trailing memory barriers guarantee that these * operations are fully ordered. @@ -48,7 +257,7 @@ __typeof__(*(ptr)) _x_ = (x); \ smp_mb(); \ __ret = (__typeof__(*(ptr))) \ - __arch_xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \ + ____xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \ smp_mb(); \ __ret; \ }) @@ -59,7 +268,7 @@ __typeof__(*(ptr)) _o_ = (o); \ __typeof__(*(ptr)) _n_ = (n); \ smp_mb(); \ - __ret = (__typeof__(*(ptr))) __cmpxchg((ptr), \ + __ret = (__typeof__(*(ptr))) ____cmpxchg((ptr), \ (unsigned long)_o_, (unsigned long)_n_, sizeof(*(ptr)));\ smp_mb(); \ __ret; \ @@ -71,6 +280,4 @@ arch_cmpxchg((ptr), (o), (n)); \ }) -#undef ____cmpxchg - #endif /* _ALPHA_CMPXCHG_H */ |