1 /*
2  * Copyright (c) 2004-2007 Voltaire, Inc. All rights reserved.
3  * Copyright (c) 2002-2005 Mellanox Technologies LTD. All rights reserved.
4  * Copyright (c) 1996-2003 Intel Corporation. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  *
34  */
35 
36 /*
37  * Abstract:
38  *	Implementation of thread pool.
39  *
40  */
41 
42 #if HAVE_CONFIG_H
43 #  include <config.h>
44 #endif				/* HAVE_CONFIG_H */
45 
46 #include <stdlib.h>
47 #include <string.h>
48 #include <pthread.h>
49 #include <complib/cl_threadpool.h>
50 
cleanup_mutex(void * arg)51 static void cleanup_mutex(void *arg)
52 {
53 	pthread_mutex_unlock(&((cl_thread_pool_t *) arg)->mutex);
54 }
55 
thread_pool_routine(void * context)56 static void *thread_pool_routine(void *context)
57 {
58 	cl_thread_pool_t *p_thread_pool = (cl_thread_pool_t *) context;
59 
60 	do {
61 		pthread_mutex_lock(&p_thread_pool->mutex);
62 		pthread_cleanup_push(cleanup_mutex, p_thread_pool);
63 		while (!p_thread_pool->events)
64 			pthread_cond_wait(&p_thread_pool->cond,
65 					  &p_thread_pool->mutex);
66 		p_thread_pool->events--;
67 		pthread_cleanup_pop(1);
68 		/* The event has been signalled.  Invoke the callback. */
69 		(*p_thread_pool->pfn_callback) (p_thread_pool->context);
70 	} while (1);
71 
72 	return NULL;
73 }
74 
75 cl_status_t
cl_thread_pool_init(IN cl_thread_pool_t * const p_thread_pool,IN unsigned count,IN void (* pfn_callback)(void *),IN void * context,IN const char * const name)76 cl_thread_pool_init(IN cl_thread_pool_t * const p_thread_pool,
77 		    IN unsigned count,
78 		    IN void (*pfn_callback) (void *),
79 		    IN void *context, IN const char *const name)
80 {
81 	int i;
82 
83 	CL_ASSERT(p_thread_pool);
84 	CL_ASSERT(pfn_callback);
85 
86 	memset(p_thread_pool, 0, sizeof(*p_thread_pool));
87 
88 	if (!count)
89 		count = cl_proc_count();
90 
91 	pthread_mutex_init(&p_thread_pool->mutex, NULL);
92 	pthread_cond_init(&p_thread_pool->cond, NULL);
93 
94 	p_thread_pool->events = 0;
95 
96 	p_thread_pool->pfn_callback = pfn_callback;
97 	p_thread_pool->context = context;
98 
99 	p_thread_pool->tid = calloc(count, sizeof(*p_thread_pool->tid));
100 	if (!p_thread_pool->tid) {
101 		cl_thread_pool_destroy(p_thread_pool);
102 		return CL_INSUFFICIENT_MEMORY;
103 	}
104 
105 	p_thread_pool->running_count = count;
106 
107 	for (i = 0; i < count; i++) {
108 		if (pthread_create(&p_thread_pool->tid[i], NULL,
109 				   thread_pool_routine, p_thread_pool) < 0) {
110 			cl_thread_pool_destroy(p_thread_pool);
111 			return CL_INSUFFICIENT_RESOURCES;
112 		}
113 	}
114 
115 	return (CL_SUCCESS);
116 }
117 
cl_thread_pool_destroy(IN cl_thread_pool_t * const p_thread_pool)118 void cl_thread_pool_destroy(IN cl_thread_pool_t * const p_thread_pool)
119 {
120 	int i;
121 
122 	CL_ASSERT(p_thread_pool);
123 
124 	for (i = 0; i < p_thread_pool->running_count; i++)
125 		if (p_thread_pool->tid[i])
126 			pthread_cancel(p_thread_pool->tid[i]);
127 
128 	for (i = 0; i < p_thread_pool->running_count; i++)
129 		if (p_thread_pool->tid[i])
130 			pthread_join(p_thread_pool->tid[i], NULL);
131 
132 	p_thread_pool->running_count = 0;
133 	pthread_cond_destroy(&p_thread_pool->cond);
134 	pthread_mutex_destroy(&p_thread_pool->mutex);
135 
136 	p_thread_pool->events = 0;
137 }
138 
cl_thread_pool_signal(IN cl_thread_pool_t * const p_thread_pool)139 cl_status_t cl_thread_pool_signal(IN cl_thread_pool_t * const p_thread_pool)
140 {
141 	int ret;
142 	CL_ASSERT(p_thread_pool);
143 	pthread_mutex_lock(&p_thread_pool->mutex);
144 	p_thread_pool->events++;
145 	ret = pthread_cond_signal(&p_thread_pool->cond);
146 	pthread_mutex_unlock(&p_thread_pool->mutex);
147 	return ret;
148 }
149