diff options
Diffstat (limited to 'db2/mutex/mutex.c')
| -rw-r--r-- | db2/mutex/mutex.c | 74 |
1 files changed, 51 insertions, 23 deletions
diff --git a/db2/mutex/mutex.c b/db2/mutex/mutex.c index 6dca323113..de0d0e23fe 100644 --- a/db2/mutex/mutex.c +++ b/db2/mutex/mutex.c @@ -1,14 +1,14 @@ /*- * See the file LICENSE for redistribution information. * - * Copyright (c) 1996, 1997 + * Copyright (c) 1996, 1997, 1998 * Sleepycat Software. All rights reserved. */ #include "config.h" #ifndef lint -static const char sccsid[] = "@(#)mutex.c 10.32 (Sleepycat) 1/16/98"; +static const char sccsid[] = "@(#)mutex.c 10.48 (Sleepycat) 5/23/98"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES @@ -16,14 +16,12 @@ static const char sccsid[] = "@(#)mutex.c 10.32 (Sleepycat) 1/16/98"; #include <errno.h> #include <fcntl.h> -#include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #endif #include "db_int.h" -#include "common_ext.h" #ifdef HAVE_SPINLOCKS @@ -43,13 +41,21 @@ static const char sccsid[] = "@(#)mutex.c 10.32 (Sleepycat) 1/16/98"; * Should we not use MSEM_IF_NOWAIT and let the system block for us? * I've no idea if this will block all threads in the process or not. */ -#define TSL_INIT(x) msem_init(x, MSEM_UNLOCKED) +#define TSL_INIT(x) (msem_init(x, MSEM_UNLOCKED) == NULL) +#define TSL_INIT_ERROR 1 #define TSL_SET(x) (!msem_lock(x, MSEM_IF_NOWAIT)) #define TSL_UNSET(x) msem_unlock(x, 0) #endif +#ifdef HAVE_FUNC_RELIANT +#define TSL_INIT(x) initspin(x, 1) +#define TSL_SET(x) (cspinlock(x) == 0) +#define TSL_UNSET(x) spinunlock(x) +#endif + #ifdef HAVE_FUNC_SGI -#define TSL_INIT(x) init_lock(x) +#define TSL_INIT(x) (init_lock(x) != 0) +#define TSL_INIT_ERROR 1 #define TSL_SET(x) (!acquire_lock(x)) #define TSL_UNSET(x) release_lock(x) #endif @@ -58,7 +64,8 @@ static const char sccsid[] = "@(#)mutex.c 10.32 (Sleepycat) 1/16/98"; /* * Semaphore calls don't work on Solaris 5.5. * - * #define TSL_INIT(x) sema_init(x, 1, USYNC_PROCESS, NULL) + * #define TSL_INIT(x) (sema_init(x, 1, USYNC_PROCESS, NULL) != 0) + * #define TSL_INIT_ERROR 1 * #define TSL_SET(x) (sema_wait(x) == 0) * #define TSL_UNSET(x) sema_post(x) */ @@ -67,6 +74,10 @@ static const char sccsid[] = "@(#)mutex.c 10.32 (Sleepycat) 1/16/98"; #define TSL_UNSET(x) _lock_clear(x) #endif +#ifdef HAVE_ASSEM_PARISC_GCC +#include "parisc.gcc" +#endif + #ifdef HAVE_ASSEM_SCO_CC #include "sco.cc" #endif @@ -85,17 +96,20 @@ static const char sccsid[] = "@(#)mutex.c 10.32 (Sleepycat) 1/16/98"; #include "x86.gcc" #endif -#if defined(_WIN32) -/* DBDB this needs to be byte-aligned!! */ +#ifdef WIN16 +/* Win16 spinlocks are simple because we cannot possibly be preempted. */ #define TSL_INIT(tsl) -#define TSL_SET(tsl) (!InterlockedExchange((PLONG)tsl, 1)) +#define TSL_SET(tsl) (*(tsl) = 1) #define TSL_UNSET(tsl) (*(tsl) = 0) #endif -#ifdef macintosh -/* Mac spinlocks are simple because we cannot possibly be preempted. */ +#if defined(_WIN32) +/* + * XXX + * DBDB this needs to be byte-aligned!! + */ #define TSL_INIT(tsl) -#define TSL_SET(tsl) (*(tsl) = 1) +#define TSL_SET(tsl) (!InterlockedExchange((PLONG)tsl, 1)) #define TSL_UNSET(tsl) (*(tsl) = 0) #endif @@ -105,14 +119,14 @@ static const char sccsid[] = "@(#)mutex.c 10.32 (Sleepycat) 1/16/98"; * __db_mutex_init -- * Initialize a DB mutex structure. * - * PUBLIC: void __db_mutex_init __P((db_mutex_t *, u_int32_t)); + * PUBLIC: int __db_mutex_init __P((db_mutex_t *, u_int32_t)); */ -void +int __db_mutex_init(mp, off) db_mutex_t *mp; u_int32_t off; { -#ifdef DEBUG +#ifdef DIAGNOSTIC if ((ALIGNTYPE)mp & (MUTEX_ALIGNMENT - 1)) { (void)fprintf(stderr, "MUTEX ERROR: mutex NOT %d-byte aligned!\n", @@ -125,11 +139,17 @@ __db_mutex_init(mp, off) #ifdef HAVE_SPINLOCKS COMPQUIET(off, 0); +#ifdef TSL_INIT_ERROR + if (TSL_INIT(&mp->tsl_resource)) + return (errno); +#else TSL_INIT(&mp->tsl_resource); +#endif mp->spins = __os_spin(); #else mp->off = off; #endif + return (0); } #define MS(n) ((n) * 1000) /* Milliseconds to micro-seconds. */ @@ -147,17 +167,25 @@ __db_mutex_lock(mp, fd) int fd; { u_long usecs; - #ifdef HAVE_SPINLOCKS int nspins; +#else + struct flock k_lock; + pid_t mypid; + int locked; +#endif + + if (!DB_GLOBAL(db_mutexlocks)) + return (0); +#ifdef HAVE_SPINLOCKS COMPQUIET(fd, 0); for (usecs = MS(10);;) { /* Try and acquire the uncontested resource lock for N spins. */ for (nspins = mp->spins; nspins > 0; --nspins) if (TSL_SET(&mp->tsl_resource)) { -#ifdef DEBUG +#ifdef DIAGNOSTIC if (mp->pid != 0) { (void)fprintf(stderr, "MUTEX ERROR: __db_mutex_lock: lock currently locked\n"); @@ -182,9 +210,6 @@ __db_mutex_lock(mp, fd) /* NOTREACHED */ #else /* !HAVE_SPINLOCKS */ - struct flock k_lock; - pid_t mypid; - int locked; /* Initialize the lock. */ k_lock.l_whence = SEEK_SET; @@ -246,7 +271,10 @@ __db_mutex_unlock(mp, fd) db_mutex_t *mp; int fd; { -#ifdef DEBUG + if (!DB_GLOBAL(db_mutexlocks)) + return (0); + +#ifdef DIAGNOSTIC if (mp->pid == 0) { (void)fprintf(stderr, "MUTEX ERROR: __db_mutex_unlock: lock already unlocked\n"); @@ -257,7 +285,7 @@ __db_mutex_unlock(mp, fd) #ifdef HAVE_SPINLOCKS COMPQUIET(fd, 0); -#ifdef DEBUG +#ifdef DIAGNOSTIC mp->pid = 0; #endif |