Makefile- atomic.h
- date.c
- date.h
- io.c
- io.h
- libxattr.c
- libxattr.h
- netbuf.c
- object.c
- object.h
- objs.mk
- pblock.c
- pblock.h
- platform.h
- plist.c
- plist.h
- plist_pvt.h
- plistdef.h
- pool.c
- pool.h
- pool_pvt.h
- shexp.c
- shexp.h
- strbuf.c
- strbuf.h
- system.c
- systems.h
- systhr.c
- systhr.h
- thrpool.c
- thrpool.h
- uri.c
- util.c
- util.h
- writer.c
- writer.h
1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 2013 Olaf Wintermann. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <unistd.h>
32
33 #include "atomic.h"
34 #include "thrpool.h"
35
36 static threadpool_job kill_job;
37
38 threadpool_t* threadpool_new(int min, int max) {
39 log_ereport(LOG_VERBOSE, "new threadpool (min: %d, max: %d)", min, max);
40 threadpool_t *pool = malloc(sizeof(threadpool_t));
41 pool->queue = NULL;
42 pool->queue_len = 0;
43 pool->num_idle = 0;
44 pool->min_threads = min;
45 pool->max_threads = max;
46 pool->num_threads = 0;
47
48 pthread_mutex_init(&pool->queue_lock, NULL);
49 pthread_mutex_init(&pool->avlbl_lock, NULL);
50 pthread_cond_init(&pool->available, NULL);
51
52 return pool;
53 }
54
55 int threadpool_start(threadpool_t *pool) {
56 /* create pool threads */
57 for(int i=0;i<pool->min_threads;i++) {
58 pthread_t t;
59 if (pthread_create(&t, NULL, threadpool_func, pool) != 0) {
60 log_ereport(LOG_FAILURE, "threadpool_start: pthread_create failed: %s", strerror(errno));
61 return 1;
62 }
63 }
64 return 0;
65 }
66
67 void* threadpool_func(void *data) {
68 threadpool_t *pool = (threadpool_t*)data;
69
70 ws_atomic_inc32(&pool->num_threads);
71 for(;;) {
72 threadpool_job *job = threadpool_get_job(pool);
73 if(job == &kill_job) {
74 break;
75 }
76
77 job->callback(job->data);
78
79 free(job);
80 }
81 uint32_t nthreads = ws_atomic_dec32(&pool->num_threads);
82 if(nthreads == 0) {
83 log_ereport(LOG_INFORM, "threadpool closed"); // TODO: log threadpool name
84 }
85 return NULL;
86 }
87
88 threadpool_job* threadpool_get_job(threadpool_t *pool) {
89 pthread_mutex_lock(&pool->queue_lock);
90
91 threadpool_job *job = NULL;
92 pool->num_idle++;
93 while(job == NULL) {
94 if(pool->queue_len == 0) {
95 pthread_cond_wait(&pool->available, &pool->queue_lock);
96 continue;
97 } else {
98 pool_queue_t *q = pool->queue;
99 job = q->job;
100 pool->queue = q->next;
101 pool->queue_len--;
102 free(q);
103 }
104 }
105 pool->num_idle--;
106
107 pthread_mutex_unlock(&pool->queue_lock);
108 return job;
109 }
110
111 void threadpool_run(threadpool_t *pool, job_callback_f func, void *data) {
112 // TODO: handle errors
113
114 if(pool->num_threads == 0) {
115 threadpool_start(pool);
116 }
117
118 threadpool_job *job = malloc(sizeof(threadpool_job));
119 job->callback = func;
120 job->data = data;
121
122 pthread_mutex_lock(&pool->queue_lock);
123 threadpool_enqueue_job(pool, job);
124
125 int create_thread = 0;
126 int destroy_thread = 0;
127 int diff = pool->queue_len - pool->num_idle;
128 if(diff > 0 && pool->num_threads < pool->max_threads) {
129 create_thread = 1;
130 } else if(diff < 0 && pool->num_threads > pool->min_threads) {
131 destroy_thread = 1;
132 }
133
134 //if(pool->queue_len == 1) {
135 pthread_cond_signal(&pool->available);
136 //}
137
138 if(create_thread) {
139 pthread_t t;
140 if (pthread_create(&t, NULL, threadpool_func, pool) != 0) {
141 log_ereport(LOG_FAILURE, "threadpool_run: pthread_create failed: %s", strerror(errno));
142 }
143 }
144 if(destroy_thread) {
145 threadpool_enqueue_job(pool, &kill_job);
146 pthread_cond_signal(&pool->available);
147 }
148
149 pthread_mutex_unlock(&pool->queue_lock);
150 }
151
152 void threadpool_enqueue_job(threadpool_t *pool, threadpool_job *job) {
153 pool_queue_t *q = malloc(sizeof(pool_queue_t));
154 q->job = job;
155 q->next = NULL;
156
157 if(pool->queue == NULL) {
158 pool->queue = q;
159 } else {
160 pool_queue_t *last_elem = pool->queue;
161 while(last_elem->next != NULL) {
162 last_elem = last_elem->next;
163 }
164 last_elem->next = q;
165 }
166 pool->queue_len++;
167 }
168
169 void threadpool_shutdown(threadpool_t *pool) {
170 int nthreads = pool->max_threads;
171 for(int i=0;i<nthreads;i++) {
172 pthread_mutex_lock(&pool->queue_lock);
173 threadpool_enqueue_job(pool, &kill_job);
174 pthread_cond_signal(&pool->available);
175 pthread_mutex_unlock(&pool->queue_lock);
176 }
177 }
178