home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
OS/2 Shareware BBS: 10 Tools
/
10-Tools.zip
/
stlpt453.zip
/
STLport-4.5.3
/
stlport
/
stl
/
_pthread_alloc.c
< prev
next >
Wrap
C/C++ Source or Header
|
2002-02-08
|
8KB
|
253 lines
/*
*
* Copyright (c) 1996,1997
* Silicon Graphics Computer Systems, Inc.
*
* Copyright (c) 1997
* Moscow Center for SPARC Technology
*
* Copyright (c) 1999
* Boris Fomitchev
*
* This material is provided "as is", with absolutely no warranty expressed
* or implied. Any use is at your own risk.
*
* Permission to use or copy this software for any purpose is hereby granted
* without fee, provided the above notices are retained on all copies.
* Permission to modify the code and to distribute modified code is granted,
* provided the above notices are retained, and a notice that the code was
* modified is included with the above copyright notice.
*
*/
#ifndef _STLP_PTHREAD_ALLOC_C
#define _STLP_PTHREAD_ALLOC_C
#ifdef __WATCOMC__
#pragma warning 13 9
#pragma warning 367 9
#pragma warning 368 9
#endif
#ifndef _STLP_PTHREAD_ALLOC_H
# include <stl/_pthread_alloc.h>
#endif
# if defined (_STLP_EXPOSE_GLOBALS_IMPLEMENTATION)
# include <cerrno>
_STLP_BEGIN_NAMESPACE
template <size_t _Max_size>
void _Pthread_alloc<_Max_size>::_S_destructor(void * __instance)
{
_M_lock __lock_instance; // Need to acquire lock here.
_Pthread_alloc_per_thread_state<_Max_size>* __s =
(_Pthread_alloc_per_thread_state<_Max_size> *)__instance;
__s -> __next = _S_free_per_thread_states;
_S_free_per_thread_states = __s;
}
template <size_t _Max_size>
_Pthread_alloc_per_thread_state<_Max_size> *
_Pthread_alloc<_Max_size>::_S_new_per_thread_state()
{
/* lock already held here. */
if (0 != _S_free_per_thread_states) {
_Pthread_alloc_per_thread_state<_Max_size> *__result =
_S_free_per_thread_states;
_S_free_per_thread_states = _S_free_per_thread_states -> __next;
return __result;
} else {
return _STLP_NEW _Pthread_alloc_per_thread_state<_Max_size>;
}
}
template <size_t _Max_size>
_Pthread_alloc_per_thread_state<_Max_size> *
_Pthread_alloc<_Max_size>::_S_get_per_thread_state()
{
int __ret_code;
__state_type* __result;
if (_S_key_initialized && (__result = (__state_type*) pthread_getspecific(_S_key)))
return __result;
/*REFERENCED*/
_M_lock __lock_instance; // Need to acquire lock here.
if (!_S_key_initialized) {
if (pthread_key_create(&_S_key, _S_destructor)) {
__THROW_BAD_ALLOC; // failed
}
_S_key_initialized = true;
}
__result = _S_new_per_thread_state();
__ret_code = pthread_setspecific(_S_key, __result);
if (__ret_code) {
if (__ret_code == ENOMEM) {
__THROW_BAD_ALLOC;
} else {
// EINVAL
_STLP_ABORT();
}
}
return __result;
}
/* We allocate memory in large chunks in order to avoid fragmenting */
/* the malloc heap too much. */
/* We assume that size is properly aligned. */
template <size_t _Max_size>
char *_Pthread_alloc<_Max_size>
::_S_chunk_alloc(size_t __p_size, size_t &__nobjs)
{
{
char * __result;
size_t __total_bytes;
size_t __bytes_left;
/*REFERENCED*/
_M_lock __lock_instance; // Acquire lock for this routine
__total_bytes = __p_size * __nobjs;
__bytes_left = _S_end_free - _S_start_free;
if (__bytes_left >= __total_bytes) {
__result = _S_start_free;
_S_start_free += __total_bytes;
return(__result);
} else if (__bytes_left >= __p_size) {
__nobjs = __bytes_left/__p_size;
__total_bytes = __p_size * __nobjs;
__result = _S_start_free;
_S_start_free += __total_bytes;
return(__result);
} else {
size_t __bytes_to_get =
2 * __total_bytes + _S_round_up(_S_heap_size >> 4);
// Try to make use of the left-over piece.
if (__bytes_left > 0) {
_Pthread_alloc_per_thread_state<_Max_size>* __a =
(_Pthread_alloc_per_thread_state<_Max_size>*)
pthread_getspecific(_S_key);
__obj * volatile * __my_free_list =
__a->__free_list + _S_freelist_index(__bytes_left);
((__obj *)_S_start_free) -> __free_list_link = *__my_free_list;
*__my_free_list = (__obj *)_S_start_free;
}
# ifdef _SGI_SOURCE
// Try to get memory that's aligned on something like a
// cache line boundary, so as to avoid parceling out
// parts of the same line to different threads and thus
// possibly different processors.
{
const int __cache_line_size = 128; // probable upper bound
__bytes_to_get &= ~(__cache_line_size-1);
_S_start_free = (char *)memalign(__cache_line_size, __bytes_to_get);
if (0 == _S_start_free) {
_S_start_free = (char *)__malloc_alloc<0>::allocate(__bytes_to_get);
}
}
# else /* !SGI_SOURCE */
_S_start_free = (char *)__malloc_alloc<0>::allocate(__bytes_to_get);
# endif
_S_heap_size += __bytes_to_get;
_S_end_free = _S_start_free + __bytes_to_get;
}
}
// lock is released here
return(_S_chunk_alloc(__p_size, __nobjs));
}
/* Returns an object of size n, and optionally adds to size n free list.*/
/* We assume that n is properly aligned. */
/* We hold the allocation lock. */
template <size_t _Max_size>
void *_Pthread_alloc_per_thread_state<_Max_size>
::_M_refill(size_t __n)
{
size_t __nobjs = 128;
char * __chunk =
_Pthread_alloc<_Max_size>::_S_chunk_alloc(__n, __nobjs);
__obj * volatile * __my_free_list;
__obj * __result;
__obj * __current_obj, * __next_obj;
int __i;
if (1 == __nobjs) {
return(__chunk);
}
__my_free_list = __free_list
+ _Pthread_alloc<_Max_size>::_S_freelist_index(__n);
/* Build free list in chunk */
__result = (__obj *)__chunk;
*__my_free_list = __next_obj = (__obj *)(__chunk + __n);
for (__i = 1; ; __i++) {
__current_obj = __next_obj;
__next_obj = (__obj *)((char *)__next_obj + __n);
if (__nobjs - 1 == __i) {
__current_obj -> __free_list_link = 0;
break;
} else {
__current_obj -> __free_list_link = __next_obj;
}
}
return(__result);
}
template <size_t _Max_size>
void *_Pthread_alloc<_Max_size>
::reallocate(void *__p, size_t __old_sz, size_t __new_sz)
{
void * __result;
size_t __copy_sz;
if (__old_sz > _Max_size
&& __new_sz > _Max_size) {
return(realloc(__p, __new_sz));
}
if (_S_round_up(__old_sz) == _S_round_up(__new_sz)) return(__p);
__result = allocate(__new_sz);
__copy_sz = __new_sz > __old_sz? __old_sz : __new_sz;
memcpy(__result, __p, __copy_sz);
deallocate(__p, __old_sz);
return(__result);
}
#if defined (_STLP_STATIC_TEMPLATE_DATA) && (_STLP_STATIC_TEMPLATE_DATA > 0)
template <size_t _Max_size>
_Pthread_alloc_per_thread_state<_Max_size> * _Pthread_alloc<_Max_size>::_S_free_per_thread_states = 0;
template <size_t _Max_size>
pthread_key_t _Pthread_alloc<_Max_size>::_S_key =0;
template <size_t _Max_size>
bool _Pthread_alloc<_Max_size>::_S_key_initialized = false;
template <size_t _Max_size>
_STLP_mutex_base _Pthread_alloc<_Max_size>::_S_chunk_allocator_lock _STLP_MUTEX_INITIALIZER;
template <size_t _Max_size>
char *_Pthread_alloc<_Max_size>::_S_start_free = 0;
template <size_t _Max_size>
char *_Pthread_alloc<_Max_size>::_S_end_free = 0;
template <size_t _Max_size>
size_t _Pthread_alloc<_Max_size>::_S_heap_size = 0;
# endif
_STLP_END_NAMESPACE
# endif /* _STLP_EXPOSE_GLOBALS_IMPLEMENTATION */
#endif /* _STLP_PTHREAD_ALLOC_C */
// Local Variables:
// mode:C++
// End: