Files
blis/frame/thread/bli_pthread.h
Field G. Van Zee 9bb23e6c2a Added support for systemless build (no pthreads).
Details:
- Added a configure option, --[enable|disable]-system, which determines
  whether the modest operating system dependencies in BLIS are included.
  The most notable example of this on Linux and BSD/OSX is the use of
  POSIX threads to ensure thread safety for when application-level
  threads call BLIS. When --disable-system is given, the bli_pthreads
  implementation is dummied out entirely, allowing the calling code
  within BLIS to remain unchanged. Why would anyone want to build BLIS
  like this? The motivating example was submitted via #454 in which a
  user wanted to build BLIS for a simulator such as gem5 where thread
  safety may not be a concern (and where the operating system is largely
  absent anyway). Thanks to Stepan Nassyr for suggesting this feature.
- Another, more minor side effect of the --disable-system option is that
  the implementation of bli_clock() unconditionally returns 0.0 instead
  of the time elapsed since some fixed point in the past. The reasoning
  for this is that if the operating system is truly minimal, the system
  function call upon which bli_clock() would normally be implemented
  (e.g. clock_gettime()) may not be available.
- Refactored preprocess-guarded code in bli_pthread.c and bli_pthread.h
  to remove redundancies.
- Removed old comments and commented #include of "bli_pthread_wrap.h"
  from bli_system.h.
- Documented bli_clock() and bli_clock_min_diff() in BLISObjectAPI.md
  and BLISTypedAPI.md, with a note that both are non-functional when
  BLIS is configured with --disable-system.
2020-11-16 15:55:45 -06:00

250 lines
7.1 KiB
C

/*
BLIS
An object-based framework for developing high-performance BLAS-like
libraries.
Copyright (C) 2018, Southern Methodist University
Copyright (C) 2018, The University of Texas at Austin
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
- Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
- Neither the name(s) of the copyright holder(s) nor the names of its
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef BLIS_PTHREAD_H
#define BLIS_PTHREAD_H
// -- Type and macro definitions -----------------------------------------------
#if defined(BLIS_DISABLE_SYSTEM)
// This branch defines a pthread-like API, bli_pthread_*(), and implements it
// in terms of "dummy" code that doesn't depend on POSIX threads or any other
// threading mechanism. See issue #454 to see the use case that prompted this
// feature.
// NOTE: THIS CODE DOES NOT IMPLEMENT THREADING AND IS NOT THREAD-SAFE!
// -- pthread types --
typedef int bli_pthread_t;
typedef int bli_pthread_attr_t;
typedef int bli_pthread_mutex_t;
typedef int bli_pthread_mutexattr_t;
typedef int bli_pthread_cond_t;
typedef int bli_pthread_condattr_t;
typedef int bli_pthread_once_t;
typedef int bli_pthread_barrier_t;
typedef int bli_pthread_barrierattr_t;
// -- pthreads macros --
#define BLIS_PTHREAD_MUTEX_INITIALIZER 0
#define BLIS_PTHREAD_COND_INITIALIZER 0
#define BLIS_PTHREAD_ONCE_INIT 0
#elif defined(_MSC_VER) // !defined(BLIS_DISABLE_SYSTEM)
// This branch defines a pthread-like API, bli_pthread_*(), and implements it
// in terms of Windows API calls.
// -- pthread types --
typedef struct
{
HANDLE handle;
void* retval;
} bli_pthread_t;
typedef void bli_pthread_attr_t;
typedef SRWLOCK bli_pthread_mutex_t;
typedef void bli_pthread_mutexattr_t;
typedef CONDITION_VARIABLE bli_pthread_cond_t;
typedef void bli_pthread_condattr_t;
typedef INIT_ONCE bli_pthread_once_t;
typedef struct
{
bli_pthread_mutex_t mutex;
bli_pthread_cond_t cond;
int count;
int tripCount;
} bli_pthread_barrier_t;
typedef void bli_pthread_barrierattr_t;
// -- pthreads macros --
#define BLIS_PTHREAD_MUTEX_INITIALIZER SRWLOCK_INIT
#define BLIS_PTHREAD_ONCE_INIT INIT_ONCE_STATIC_INIT
#define BLIS_PTHREAD_COND_INITIALIZER CONDITION_VARIABLE_INIT
#else // !defined(BLIS_DISABLE_SYSTEM) && !defined(_MSC_VER)
#include <pthread.h>
// This branch defines a pthreads-like API, bli_pthreads_*(), and implements it
// in terms of the corresponding pthreads_*() types, macros, and function calls.
// -- pthread types --
typedef pthread_t bli_pthread_t;
typedef pthread_attr_t bli_pthread_attr_t;
typedef pthread_mutex_t bli_pthread_mutex_t;
typedef pthread_mutexattr_t bli_pthread_mutexattr_t;
typedef pthread_cond_t bli_pthread_cond_t;
typedef pthread_condattr_t bli_pthread_condattr_t;
typedef pthread_once_t bli_pthread_once_t;
#if defined(__APPLE__)
// For OS X, we must define the barrier types ourselves since Apple does
// not implement barriers in their variant of pthreads.
typedef void bli_pthread_barrierattr_t;
typedef struct
{
bli_pthread_mutex_t mutex;
bli_pthread_cond_t cond;
int count;
int tripCount;
} bli_pthread_barrier_t;
#else
// For other non-Windows OSes (primarily Linux), we can define the barrier
// types in terms of existing pthreads barrier types since we expect they
// will be provided by the pthreads implementation.
typedef pthread_barrier_t bli_pthread_barrier_t;
typedef pthread_barrierattr_t bli_pthread_barrierattr_t;
#endif
// -- pthreads macros --
#define BLIS_PTHREAD_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER
#define BLIS_PTHREAD_COND_INITIALIZER PTHREAD_COND_INITIALIZER
#define BLIS_PTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
#endif
// -- Function definitions -----------------------------------------------------
// -- pthread_create(), pthread_join() --
BLIS_EXPORT_BLIS int bli_pthread_create
(
bli_pthread_t* thread,
const bli_pthread_attr_t* attr,
void* (*start_routine)(void*),
void* arg
);
BLIS_EXPORT_BLIS int bli_pthread_join
(
bli_pthread_t thread,
void** retval
);
// -- pthread_mutex_*() --
BLIS_EXPORT_BLIS int bli_pthread_mutex_init
(
bli_pthread_mutex_t* mutex,
const bli_pthread_mutexattr_t* attr
);
BLIS_EXPORT_BLIS int bli_pthread_mutex_destroy
(
bli_pthread_mutex_t* mutex
);
BLIS_EXPORT_BLIS int bli_pthread_mutex_lock
(
bli_pthread_mutex_t* mutex
);
BLIS_EXPORT_BLIS int bli_pthread_mutex_trylock
(
bli_pthread_mutex_t* mutex
);
BLIS_EXPORT_BLIS int bli_pthread_mutex_unlock
(
bli_pthread_mutex_t* mutex
);
// -- pthread_cond_*() --
BLIS_EXPORT_BLIS int bli_pthread_cond_init
(
bli_pthread_cond_t* cond,
const bli_pthread_condattr_t* attr
);
BLIS_EXPORT_BLIS int bli_pthread_cond_destroy
(
bli_pthread_cond_t* cond
);
BLIS_EXPORT_BLIS int bli_pthread_cond_wait
(
bli_pthread_cond_t* cond,
bli_pthread_mutex_t* mutex
);
BLIS_EXPORT_BLIS int bli_pthread_cond_broadcast
(
bli_pthread_cond_t* cond
);
// -- pthread_once_*() --
BLIS_EXPORT_BLIS void bli_pthread_once
(
bli_pthread_once_t* once,
void (*init)(void)
);
// -- pthread_barrier_*() --
BLIS_EXPORT_BLIS int bli_pthread_barrier_init
(
bli_pthread_barrier_t* barrier,
const bli_pthread_barrierattr_t* attr,
unsigned int count
);
BLIS_EXPORT_BLIS int bli_pthread_barrier_destroy
(
bli_pthread_barrier_t* barrier
);
BLIS_EXPORT_BLIS int bli_pthread_barrier_wait
(
bli_pthread_barrier_t* barrier
);
#endif // BLIS_PTHREAD_H