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openmpi/opal/threads/mutex.h
Eugene Loh 2770a12beb Continue clean up of thread options started in r22841, 22842, and 22849.
No need for any CMRs to 1.5... that was already done in CMR 2728.

This commit was SVN r24545.

The following SVN revision numbers were found above:
  r22841 --> open-mpi/ompi@b400b84162
2011-03-18 21:36:35 +00:00

414 строки
14 KiB
C

/*
* Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
* University Research and Technology
* Corporation. All rights reserved.
* Copyright (c) 2004-2006 The University of Tennessee and The University
* of Tennessee Research Foundation. All rights
* reserved.
* Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
* University of Stuttgart. All rights reserved.
* Copyright (c) 2004-2005 The Regents of the University of California.
* All rights reserved.
* Copyright (c) 2007 Cisco Systems, Inc. All rights reserved.
* Copyright (c) 2007 Los Alamos National Security, LLC. All rights
* reserved.
* Copyright (c) 2007 Voltaire. All rights reserved.
* Copyright (c) 2010 Oracle and/or its affiliates. All rights reserved.
*
* $COPYRIGHT$
*
* Additional copyrights may follow
*
* $HEADER$
*/
#ifndef OPAL_MUTEX_H
#define OPAL_MUTEX_H 1
#include "opal_config.h"
#if OPAL_ENABLE_MULTI_THREADS
#include "opal/sys/atomic.h"
#endif /* OPAL_ENABLE_MULTI_THREADS */
#if OPAL_ENABLE_DEBUG
#include "opal/util/output.h"
#endif
BEGIN_C_DECLS
/**
* @file:
*
* Mutual exclusion functions.
*
* Functions for locking of critical sections.
*/
/*
* declaring this here so that CL does not complain
*/
OPAL_DECLSPEC extern bool opal_uses_threads;
#if OPAL_ENABLE_DEBUG
OPAL_DECLSPEC extern bool opal_mutex_check_locks;
#endif
/**
* Opaque mutex object
*/
typedef struct opal_mutex_t opal_mutex_t;
/**
* Try to acquire a mutex.
*
* @param mutex Address of the mutex.
* @return 0 if the mutex was acquired, 1 otherwise.
*/
static inline int opal_mutex_trylock(opal_mutex_t *mutex);
/**
* Acquire a mutex.
*
* @param mutex Address of the mutex.
*/
static inline void opal_mutex_lock(opal_mutex_t *mutex);
/**
* Release a mutex.
*
* @param mutex Address of the mutex.
*/
static inline void opal_mutex_unlock(opal_mutex_t *mutex);
/**
* Try to acquire a mutex using atomic operations.
*
* @param mutex Address of the mutex.
* @return 0 if the mutex was acquired, 1 otherwise.
*/
static inline int opal_mutex_atomic_trylock(opal_mutex_t *mutex);
/**
* Acquire a mutex using atomic operations.
*
* @param mutex Address of the mutex.
*/
static inline void opal_mutex_atomic_lock(opal_mutex_t *mutex);
/**
* Release a mutex using atomic operations.
*
* @param mutex Address of the mutex.
*/
static inline void opal_mutex_atomic_unlock(opal_mutex_t *mutex);
END_C_DECLS
#ifdef __WINDOWS__
#include "mutex_windows.h"
#else
#include "mutex_unix.h"
#endif
BEGIN_C_DECLS
/**
* Check and see if the process is using multiple threads.
*
* @retval true If the process may have more than one thread.
* @retval false If the process only has a single thread.
*
* The value that this function returns is influenced by:
*
* - how MPI_INIT or MPI_INIT_THREAD was invoked,
* - what the final MPI thread level was determined to be,
* - whether the OMPI or MPI libraries are multi-threaded (Jan 2003:
* they're not),
* - whether configure determined if we have thread support or not
*
* MPI_INIT and MPI_INIT_THREAD (specifically, back-end OMPI startup
* functions) invoke opal_set_using_threads() to influence the value of
* this function, depending on their situation. Some examples:
*
* - if configure determined that we do not have threads, then this
* value will always be false.
*
* - if MPI_INIT is invoked, and the ompi libraries are [still]
* single-threaded, this value will be false.
*
* - if MPI_INIT_THREAD is invoked with MPI_THREAD_MULTIPLE, we have
* thread support, and the final thread level is determined to be
* MPI_THREAD_MULTIPLE, this value will be true.
*
* - if the process is a single-threaded OMPI executable (e.g., mpicc),
* this value will be false.
*
* Hence, this function will return false if there is guaranteed to
* only be one thread in the process. If there is even the
* possibility that we may have multiple threads, true will be
* returned.
*/
#define opal_using_threads() opal_uses_threads
/**
* Set whether the process is using multiple threads or not.
*
* @param have Boolean indicating whether the process is using
* multiple threads or not.
*
* @retval opal_using_threads The new return value from
* opal_using_threads().
*
* This function is used to influence the return value of
* opal_using_threads(). If configure detected that we have thread
* support, the return value of future invocations of
* opal_using_threads() will be the parameter's value. If configure
* detected that we have no thread support, then the retuen from
* opal_using_threads() will always be false.
*/
static inline bool opal_set_using_threads(bool have)
{
#if OPAL_ENABLE_MULTI_THREADS
opal_uses_threads = have;
#else
have = have; /* just shut up the compiler */
opal_uses_threads = false;
#endif
return opal_uses_threads;
}
/**
* Lock a mutex if opal_using_threads() says that multiple threads may
* be active in the process.
*
* @param mutex Pointer to a opal_mutex_t to lock.
*
* If there is a possibility that multiple threads are running in the
* process (as determined by opal_using_threads()), this function will
* block waiting to lock the mutex.
*
* If there is no possibility that multiple threads are running in the
* process, return immediately.
*/
#if OPAL_ENABLE_MULTI_THREADS
#define OPAL_THREAD_LOCK(mutex) \
do { \
if (opal_using_threads()) { \
opal_mutex_lock(mutex); \
} \
} while (0)
#elif OPAL_ENABLE_DEBUG
#define OPAL_THREAD_LOCK(mutex) \
do { \
(mutex)->m_lock_debug++; \
if (opal_mutex_check_locks && 1 != (mutex)->m_lock_debug) { \
opal_output(0, "Warning -- mutex already locked at %s:%d," \
" now at %s:%d", \
(mutex)->m_lock_file, \
(mutex)->m_lock_line, \
__FILE__, __LINE__); \
} \
(mutex)->m_lock_file = __FILE__; \
(mutex)->m_lock_line = __LINE__; \
} while (0)
#else
#define OPAL_THREAD_LOCK(mutex)
#endif
/**
* Try to lock a mutex if opal_using_threads() says that multiple
* threads may be active in the process.
*
* @param mutex Pointer to a opal_mutex_t to trylock
*
* If there is a possibility that multiple threads are running in the
* process (as determined by opal_using_threads()), this function will
* trylock the mutex.
*
* If there is no possibility that multiple threads are running in the
* process, return immediately without modifying the mutex.
*
* Returns 0 if mutex was locked, non-zero otherwise.
*/
#if OPAL_ENABLE_MULTI_THREADS
#define OPAL_THREAD_TRYLOCK(mutex) (opal_using_threads() ? opal_mutex_trylock(mutex) : 0)
#elif OPAL_ENABLE_DEBUG
static inline int
opal_thread_debug_trylock(opal_mutex_t *mutex, const char *file, int line)
{
int ret = -1;
if (0 == (mutex)->m_lock_debug) {
(mutex)->m_lock_debug++;
(mutex)->m_lock_file = file;
(mutex)->m_lock_line = line;
ret = 0;
} else {
if (opal_mutex_check_locks) {
opal_output(0, "Warning -- during trylock, mutex already locked at %s:%d "
"now at %s:%d",
file, line,
(mutex)->m_lock_file,
(mutex)->m_lock_line);
}
}
return ret;
}
#define OPAL_THREAD_TRYLOCK(mutex) opal_thread_debug_trylock(mutex, __FILE__, __LINE__)
#else
#define OPAL_THREAD_TRYLOCK(mutex) 0
#endif
/**
* Unlock a mutex if opal_using_threads() says that multiple threads
* may be active in the process.
*
* @param mutex Pointer to a opal_mutex_t to unlock.
*
* If there is a possibility that multiple threads are running in the
* process (as determined by opal_using_threads()), this function will
* unlock the mutex.
*
* If there is no possibility that multiple threads are running in the
* process, return immediately without modifying the mutex.
*/
#if OPAL_ENABLE_MULTI_THREADS
#define OPAL_THREAD_UNLOCK(mutex) \
do { \
if (opal_using_threads()) { \
opal_mutex_unlock(mutex); \
} \
} while (0)
#elif OPAL_ENABLE_DEBUG
#define OPAL_THREAD_UNLOCK(mutex) \
do { \
(mutex)->m_lock_debug--; \
if (opal_mutex_check_locks && 0 > (mutex)->m_lock_debug) { \
opal_output(0, "Warning -- mutex was double locked from %s:%d", \
__FILE__, __LINE__); \
} else if (opal_mutex_check_locks && 0 > (mutex)->m_lock_debug) { \
opal_output(0, "Warning -- mutex not locked from %s:%d", \
__FILE__, __LINE__); \
} else { \
(mutex)->m_lock_file = NULL; \
(mutex)->m_lock_line = 0; \
} \
} while (0)
#else
#define OPAL_THREAD_UNLOCK(mutex)
#endif
/**
* Lock a mutex if opal_using_threads() says that multiple threads may
* be active in the process for the duration of the specified action.
*
* @param mutex Pointer to a opal_mutex_t to lock.
* @param action A scope over which the lock is held.
*
* If there is a possibility that multiple threads are running in the
* process (as determined by opal_using_threads()), this function will
* acquire the lock before invoking the specified action and release
* it on return.
*
* If there is no possibility that multiple threads are running in the
* process, invoke the action without acquiring the lock.
*/
#if OPAL_ENABLE_MULTI_THREADS
#define OPAL_THREAD_SCOPED_LOCK(mutex, action) \
do { \
if(opal_using_threads()) { \
opal_mutex_lock(mutex); \
(action); \
opal_mutex_unlock(mutex); \
} else { \
(action); \
} \
} while (0)
#elif OPAL_ENABLE_DEBUG
#define OPAL_THREAD_SCOPED_LOCK(mutex, action) \
do { \
if (0 != (mutex)->m_lock_debug) { \
opal_output(0, "scoped_lock: Warning -- mutex already " \
"locked at %s:%d, now at %s:%d", \
__FILE__, __LINE__, \
(mutex)->m_lock_file, \
(mutex)->m_lock_line); \
} \
(mutex)->m_lock_debug--; \
(action); \
(mutex)->m_lock_debug++; \
} while (0)
#else
#define OPAL_THREAD_SCOPED_LOCK(mutex, action) (action)
#endif
/**
* Use an atomic operation for increment/decrement if opal_using_threads()
* indicates that threads are in use by the application or library.
*/
#if OPAL_ENABLE_MULTI_THREADS
#define OPAL_THREAD_ADD32(x,y) \
(opal_using_threads() ? opal_atomic_add_32(x,y) : (*x += y))
#else
#define OPAL_THREAD_ADD32(x,y) (*x += y)
#endif
#if OPAL_ENABLE_MULTI_THREADS
#define OPAL_THREAD_ADD64(x,y) \
(opal_using_threads() ? opal_atomic_add_64(x,y) : (*x += y))
#else
#define OPAL_THREAD_ADD64(x,y) (*x += y)
#endif
#if OPAL_ENABLE_MULTI_THREADS
#define OPAL_THREAD_ADD_SIZE_T(x,y) \
(opal_using_threads() ? opal_atomic_add_size_t(x,y) : (*x += y))
#else
#define OPAL_THREAD_ADD_SIZE_T(x,y) (*x += y)
#endif
#define OPAL_CMPSET(x, y, z) ((*(x) == (y)) ? ((*(x) = (z)), 1) : 0)
#if OPAL_ENABLE_MULTI_THREADS
# if OPAL_HAVE_ATOMIC_CMPSET_32
# define OPAL_ATOMIC_CMPSET_32(x, y, z) \
(opal_using_threads() ? opal_atomic_cmpset_32(x, y, z) : OPAL_CMPSET(x, y, z))
# endif
# if OPAL_HAVE_ATOMIC_CMPSET_64
# define OPAL_ATOMIC_CMPSET_64(x, y, z) \
(opal_using_threads() ? opal_atomic_cmpset_64(x, y, z) : OPAL_CMPSET(x, y, z))
# endif
# if OPAL_HAVE_ATOMIC_CMPSET_32 || OPAL_HAVE_ATOMIC_CMPSET_64
# define OPAL_ATOMIC_CMPSET(x, y, z) \
(opal_using_threads() ? opal_atomic_cmpset(x, y, z) : OPAL_CMPSET(x, y, z))
# endif
#else
# if OPAL_HAVE_ATOMIC_CMPSET_32
# define OPAL_ATOMIC_CMPSET_32(x, y, z) OPAL_CMPSET(x, y, z)
# endif
# if OPAL_HAVE_ATOMIC_CMPSET_64
# define OPAL_ATOMIC_CMPSET_64(x, y, z) OPAL_CMPSET(x, y, z)
# endif
# if OPAL_HAVE_ATOMIC_CMPSET_32 || OPAL_HAVE_ATOMIC_CMPSET_64
# define OPAL_ATOMIC_CMPSET(x, y, z) OPAL_CMPSET(x, y, z)
# endif
#endif
END_C_DECLS
#endif /* OPAL_MUTEX_H */