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Diffstat (limited to 'mysql/thr_mutex.h')
| -rw-r--r-- | mysql/thr_mutex.h | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/mysql/thr_mutex.h b/mysql/thr_mutex.h new file mode 100644 index 0000000..1b8c9d8 --- /dev/null +++ b/mysql/thr_mutex.h @@ -0,0 +1,227 @@ +#ifndef THR_MUTEX_INCLUDED +#define THR_MUTEX_INCLUDED + +/* Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ + +/** + MySQL mutex implementation. + + There are three "layers": + 1) native_mutex_*() + Functions that map directly down to OS primitives. + Windows - CriticalSection + Other OSes - pthread + 2) my_mutex_*() + Functions that implement SAFE_MUTEX (default for debug), + Otherwise native_mutex_*() is used. + 3) mysql_mutex_*() + Functions that include Performance Schema instrumentation. + See include/mysql/psi/mysql_thread.h +*/ + +#include <my_global.h> +#include "my_thread.h" + +C_MODE_START + +#ifdef _WIN32 +typedef CRITICAL_SECTION native_mutex_t; +typedef int native_mutexattr_t; +#else +typedef pthread_mutex_t native_mutex_t; +typedef pthread_mutexattr_t native_mutexattr_t; +#endif + +/* Define mutex types, see my_thr_init.c */ +#define MY_MUTEX_INIT_SLOW NULL + +/* Can be set in /usr/include/pthread.h */ +#ifdef PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP +extern native_mutexattr_t my_fast_mutexattr; +#define MY_MUTEX_INIT_FAST &my_fast_mutexattr +#else +#define MY_MUTEX_INIT_FAST NULL +#endif + +/* Can be set in /usr/include/pthread.h */ +#ifdef PTHREAD_ERRORCHECK_MUTEX_INITIALIZER_NP +extern native_mutexattr_t my_errorcheck_mutexattr; +#define MY_MUTEX_INIT_ERRCHK &my_errorcheck_mutexattr +#else +#define MY_MUTEX_INIT_ERRCHK NULL +#endif + +static inline int native_mutex_init(native_mutex_t *mutex, + const native_mutexattr_t *attr) +{ +#ifdef _WIN32 + InitializeCriticalSection(mutex); + return 0; +#else + return pthread_mutex_init(mutex, attr); +#endif +} + +static inline int native_mutex_lock(native_mutex_t *mutex) +{ +#ifdef _WIN32 + EnterCriticalSection(mutex); + return 0; +#else + return pthread_mutex_lock(mutex); +#endif +} + +static inline int native_mutex_trylock(native_mutex_t *mutex) +{ +#ifdef _WIN32 + if (TryEnterCriticalSection(mutex)) + { + /* Don't allow recursive lock */ + if (mutex->RecursionCount > 1){ + LeaveCriticalSection(mutex); + return EBUSY; + } + return 0; + } + return EBUSY; +#else + return pthread_mutex_trylock(mutex); +#endif +} + +static inline int native_mutex_unlock(native_mutex_t *mutex) +{ +#ifdef _WIN32 + LeaveCriticalSection(mutex); + return 0; +#else + return pthread_mutex_unlock(mutex); +#endif +} + +static inline int native_mutex_destroy(native_mutex_t *mutex) +{ +#ifdef _WIN32 + DeleteCriticalSection(mutex); + return 0; +#else + return pthread_mutex_destroy(mutex); +#endif +} + + +#ifdef SAFE_MUTEX +/* safe_mutex adds checking to mutex for easier debugging */ +typedef struct st_safe_mutex_t +{ + native_mutex_t global, mutex; + const char *file; + uint line, count; + my_thread_t thread; +} my_mutex_t; + +void safe_mutex_global_init(); +int safe_mutex_init(my_mutex_t *mp, const native_mutexattr_t *attr, + const char *file, uint line); +int safe_mutex_lock(my_mutex_t *mp, my_bool try_lock, const char *file, uint line); +int safe_mutex_unlock(my_mutex_t *mp, const char *file, uint line); +int safe_mutex_destroy(my_mutex_t *mp, const char *file, uint line); + +static inline void safe_mutex_assert_owner(const my_mutex_t *mp) +{ + DBUG_ASSERT(mp->count > 0 && + my_thread_equal(my_thread_self(), mp->thread)); +} + +static inline void safe_mutex_assert_not_owner(const my_mutex_t *mp) +{ + DBUG_ASSERT(!mp->count || + !my_thread_equal(my_thread_self(), mp->thread)); +} + +#else +typedef native_mutex_t my_mutex_t; +#endif + +static inline int my_mutex_init(my_mutex_t *mp, const native_mutexattr_t *attr +#ifdef SAFE_MUTEX + , const char *file, uint line +#endif + ) +{ +#ifdef SAFE_MUTEX + return safe_mutex_init(mp, attr, file, line); +#else + return native_mutex_init(mp, attr); +#endif +} + +static inline int my_mutex_lock(my_mutex_t *mp +#ifdef SAFE_MUTEX + , const char *file, uint line +#endif + ) +{ +#ifdef SAFE_MUTEX + return safe_mutex_lock(mp, FALSE, file, line); +#else + return native_mutex_lock(mp); +#endif +} + +static inline int my_mutex_trylock(my_mutex_t *mp +#ifdef SAFE_MUTEX + , const char *file, uint line +#endif + ) +{ +#ifdef SAFE_MUTEX + return safe_mutex_lock(mp, TRUE, file, line); +#else + return native_mutex_trylock(mp); +#endif +} + +static inline int my_mutex_unlock(my_mutex_t *mp +#ifdef SAFE_MUTEX + , const char *file, uint line +#endif + ) +{ +#ifdef SAFE_MUTEX + return safe_mutex_unlock(mp, file, line); +#else + return native_mutex_unlock(mp); +#endif +} + +static inline int my_mutex_destroy(my_mutex_t *mp +#ifdef SAFE_MUTEX + , const char *file, uint line +#endif + ) +{ +#ifdef SAFE_MUTEX + return safe_mutex_destroy(mp, file, line); +#else + return native_mutex_destroy(mp); +#endif +} + +C_MODE_END + +#endif /* THR_MUTEX_INCLUDED */ |