diff options
| -rw-r--r-- | sys/arch/alpha/alpha/mutex.c | 114 | ||||
| -rw-r--r-- | sys/arch/alpha/include/mutex.h | 19 |
2 files changed, 55 insertions, 78 deletions
diff --git a/sys/arch/alpha/alpha/mutex.c b/sys/arch/alpha/alpha/mutex.c index 9f204d6a288..345b94853bc 100644 --- a/sys/arch/alpha/alpha/mutex.c +++ b/sys/arch/alpha/alpha/mutex.c @@ -1,4 +1,4 @@ -/* $OpenBSD: mutex.c,v 1.13 2015/02/11 01:15:06 dlg Exp $ */ +/* $OpenBSD: mutex.c,v 1.14 2015/04/17 12:38:54 dlg Exp $ */ /* * Copyright (c) 2004 Artur Grabowski <art@openbsd.org> @@ -28,114 +28,102 @@ #include <sys/param.h> #include <sys/mutex.h> #include <sys/systm.h> +#include <sys/atomic.h> #include <machine/intr.h> #include <machine/lock.h> #include <ddb/db_output.h> -static inline int -try_lock(struct mutex *mtx) -{ -#ifdef MULTIPROCESSOR - unsigned long t0, v0; - - __asm volatile( - "1: ldl_l %0, %3 \n" /* t0 = mtx->mtx_lock */ - " bne %0, 2f \n" - " bis $31, 1, %0 \n" /* t0 = 1 */ - " stl_c %0, %2 \n" /* mtx->mtx_lock = 1 */ - " beq %0, 3f \n" - " mb \n" - " bis $31, 1, %1 \n" /* v0 = 1 */ - " br 4f \n" - "3: br 1b \n" /* update failed */ - "2: bis $31, $31, %1 \n" /* v0 = 0 */ - "4: \n" - : "=&r" (t0), "=r" (v0), "=m" (mtx->mtx_lock) - : "m" (mtx->mtx_lock) - : "memory"); - - return (v0 != 0); -#else - mtx->mtx_lock = 1; - return 1; -#endif -} - void __mtx_init(struct mutex *mtx, int wantipl) { + mtx->mtx_owner = NULL; mtx->mtx_oldipl = IPL_NONE; mtx->mtx_wantipl = wantipl; - mtx->mtx_lock = 0; -#ifdef MULTIPROCESSOR - mtx->mtx_owner = NULL; -#endif } +#ifdef MULTIPROCESSOR void mtx_enter(struct mutex *mtx) { - int s; - - for (;;) { - if (mtx->mtx_wantipl != IPL_NONE) - s = _splraise(mtx->mtx_wantipl); - if (try_lock(mtx)) { - if (mtx->mtx_wantipl != IPL_NONE) - mtx->mtx_oldipl = s; - mtx->mtx_owner = curcpu(); -#ifdef DIAGNOSTIC - curcpu()->ci_mutex_level++; -#endif - return; - } - if (mtx->mtx_wantipl != IPL_NONE) - splx(s); - -#ifdef MULTIPROCESSOR + while (mtx_enter_try(mtx) == 0) SPINLOCK_SPIN_HOOK; -#endif - } } int mtx_enter_try(struct mutex *mtx) { + struct cpu_info *owner, *ci = curcpu(); int s; if (mtx->mtx_wantipl != IPL_NONE) s = _splraise(mtx->mtx_wantipl); - if (try_lock(mtx)) { + + owner = atomic_cas_ptr(&mtx->mtx_owner, NULL, ci); +#ifdef DIAGNOSTIC + if (__predict_false(owner == ci)) + panic("mtx %p: locking against myself", mtx); +#endif + if (owner == NULL) { if (mtx->mtx_wantipl != IPL_NONE) mtx->mtx_oldipl = s; - mtx->mtx_owner = curcpu(); #ifdef DIAGNOSTIC - curcpu()->ci_mutex_level++; + ci->ci_mutex_level++; #endif - return 1; + membar_enter(); + return (1); } + if (mtx->mtx_wantipl != IPL_NONE) splx(s); - return 0; + + return (0); +} +#else +void +mtx_enter(struct mutex *mtx) +{ + struct cpu_info *ci = curcpu(); + +#ifdef DIAGNOSTIC + if (__predict_false(mtx->mtx_owner == ci)) + panic("mtx %p: locking against myself", mtx); +#endif + if (mtx->mtx_wantipl != IPL_NONE) + mtx->mtx_oldipl = _splraise(mtx->mtx_wantipl); + + mtx->mtx_owner = ci; + +#ifdef DIAGNOSTIC + ci->ci_mutex_level++; +#endif } +int +mtx_enter_try(struct mutex *mtx) +{ + mtx_enter(mtx); + return (1); +} +#endif + void mtx_leave(struct mutex *mtx) { int s; MUTEX_ASSERT_LOCKED(mtx); + +#ifdef MULTIPROCESSOR + membar_exit(); +#endif #ifdef DIAGNOSTIC curcpu()->ci_mutex_level--; #endif + s = mtx->mtx_oldipl; mtx->mtx_owner = NULL; - mtx->mtx_lock = 0; -#ifdef MULTIPROCESSOR - alpha_wmb(); -#endif if (mtx->mtx_wantipl != IPL_NONE) splx(s); } diff --git a/sys/arch/alpha/include/mutex.h b/sys/arch/alpha/include/mutex.h index a4aeca3c63d..c5509881c5a 100644 --- a/sys/arch/alpha/include/mutex.h +++ b/sys/arch/alpha/include/mutex.h @@ -1,4 +1,4 @@ -/* $OpenBSD: mutex.h,v 1.6 2014/03/18 21:09:28 kettenis Exp $ */ +/* $OpenBSD: mutex.h,v 1.7 2015/04/17 12:38:54 dlg Exp $ */ /* * Copyright (c) 2004 Artur Grabowski <art@openbsd.org> @@ -29,10 +29,9 @@ #define _MACHINE_MUTEX_H_ struct mutex { - int mtx_lock; + void *mtx_owner; int mtx_wantipl; int mtx_oldipl; - void *mtx_owner; }; /* @@ -49,29 +48,19 @@ struct mutex { #define __MUTEX_IPL(ipl) (ipl) #endif -#define MUTEX_INITIALIZER(ipl) { 0, __MUTEX_IPL((ipl)), IPL_NONE, NULL } +#define MUTEX_INITIALIZER(ipl) { NULL, __MUTEX_IPL((ipl)), IPL_NONE } void __mtx_init(struct mutex *, int); #define mtx_init(mtx, ipl) __mtx_init((mtx), __MUTEX_IPL((ipl))) #ifdef DIAGNOSTIC -#ifdef MULTIPROCESSOR #define MUTEX_ASSERT_LOCKED(mtx) do { \ - if ((mtx)->mtx_lock == 0) \ - panic("mutex %p not held in %s", (mtx), __func__); \ if ((mtx)->mtx_owner != curcpu()) \ - panic("mutex %p held by cpu %p in %s", \ - (mtx), (mtx)->mtx_owner, __func__); \ -} while (0) -#else -#define MUTEX_ASSERT_LOCKED(mtx) do { \ - if ((mtx)->mtx_lock == 0) \ panic("mutex %p not held in %s", (mtx), __func__); \ } while (0) -#endif #define MUTEX_ASSERT_UNLOCKED(mtx) do { \ - if ((mtx)->mtx_lock != 0) \ + if ((mtx)->mtx_owner == curcpu()) \ panic("mutex %p held in %s", (mtx), __func__); \ } while (0) #else |