avfilter/ff_filter_frame_needs_framing: fix handling of AV_NOPTS_VALUE
[ffmpeg.git] / libavfilter / pthread.c
1 /*
2  *
3  * This file is part of FFmpeg.
4  *
5  * FFmpeg is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2.1 of the License, or (at your option) any later version.
9  *
10  * FFmpeg is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public
16  * License along with FFmpeg; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19
20 /**
21  * @file
22  * Libavfilter multithreading support
23  */
24
25 #include "config.h"
26
27 #include "libavutil/common.h"
28 #include "libavutil/cpu.h"
29 #include "libavutil/mem.h"
30
31 #include "avfilter.h"
32 #include "internal.h"
33 #include "thread.h"
34
35 #if HAVE_PTHREADS
36 #include <pthread.h>
37 #elif HAVE_OS2THREADS
38 #include "compat/os2threads.h"
39 #elif HAVE_W32THREADS
40 #include "compat/w32pthreads.h"
41 #endif
42
43 typedef struct ThreadContext {
44     AVFilterGraph *graph;
45
46     int nb_threads;
47     pthread_t *workers;
48     avfilter_action_func *func;
49
50     /* per-execute perameters */
51     AVFilterContext *ctx;
52     void *arg;
53     int   *rets;
54     int nb_rets;
55     int nb_jobs;
56
57     pthread_cond_t last_job_cond;
58     pthread_cond_t current_job_cond;
59     pthread_mutex_t current_job_lock;
60     int current_job;
61     int done;
62 } ThreadContext;
63
64 static void* attribute_align_arg worker(void *v)
65 {
66     ThreadContext *c = v;
67     int our_job      = c->nb_jobs;
68     int nb_threads   = c->nb_threads;
69     int self_id;
70
71     pthread_mutex_lock(&c->current_job_lock);
72     self_id = c->current_job++;
73     for (;;) {
74         while (our_job >= c->nb_jobs) {
75             if (c->current_job == nb_threads + c->nb_jobs)
76                 pthread_cond_signal(&c->last_job_cond);
77
78             pthread_cond_wait(&c->current_job_cond, &c->current_job_lock);
79             our_job = self_id;
80
81             if (c->done) {
82                 pthread_mutex_unlock(&c->current_job_lock);
83                 return NULL;
84             }
85         }
86         pthread_mutex_unlock(&c->current_job_lock);
87
88         c->rets[our_job % c->nb_rets] = c->func(c->ctx, c->arg, our_job, c->nb_jobs);
89
90         pthread_mutex_lock(&c->current_job_lock);
91         our_job = c->current_job++;
92     }
93 }
94
95 static void slice_thread_uninit(ThreadContext *c)
96 {
97     int i;
98
99     pthread_mutex_lock(&c->current_job_lock);
100     c->done = 1;
101     pthread_cond_broadcast(&c->current_job_cond);
102     pthread_mutex_unlock(&c->current_job_lock);
103
104     for (i = 0; i < c->nb_threads; i++)
105          pthread_join(c->workers[i], NULL);
106
107     pthread_mutex_destroy(&c->current_job_lock);
108     pthread_cond_destroy(&c->current_job_cond);
109     pthread_cond_destroy(&c->last_job_cond);
110     av_freep(&c->workers);
111 }
112
113 static void slice_thread_park_workers(ThreadContext *c)
114 {
115     pthread_cond_wait(&c->last_job_cond, &c->current_job_lock);
116     pthread_mutex_unlock(&c->current_job_lock);
117 }
118
119 static int thread_execute(AVFilterContext *ctx, avfilter_action_func *func,
120                           void *arg, int *ret, int nb_jobs)
121 {
122     ThreadContext *c = ctx->graph->internal->thread;
123     int dummy_ret;
124
125     if (nb_jobs <= 0)
126         return 0;
127
128     pthread_mutex_lock(&c->current_job_lock);
129
130     c->current_job = c->nb_threads;
131     c->nb_jobs     = nb_jobs;
132     c->ctx         = ctx;
133     c->arg         = arg;
134     c->func        = func;
135     if (ret) {
136         c->rets    = ret;
137         c->nb_rets = nb_jobs;
138     } else {
139         c->rets    = &dummy_ret;
140         c->nb_rets = 1;
141     }
142     pthread_cond_broadcast(&c->current_job_cond);
143
144     slice_thread_park_workers(c);
145
146     return 0;
147 }
148
149 static int thread_init_internal(ThreadContext *c, int nb_threads)
150 {
151     int i, ret;
152
153     if (!nb_threads) {
154         int nb_cpus = av_cpu_count();
155         // use number of cores + 1 as thread count if there is more than one
156         if (nb_cpus > 1)
157             nb_threads = nb_cpus + 1;
158         else
159             nb_threads = 1;
160     }
161
162     if (nb_threads <= 1)
163         return 1;
164
165     c->nb_threads = nb_threads;
166     c->workers = av_mallocz(sizeof(*c->workers) * nb_threads);
167     if (!c->workers)
168         return AVERROR(ENOMEM);
169
170     c->current_job = 0;
171     c->nb_jobs     = 0;
172     c->done        = 0;
173
174     pthread_cond_init(&c->current_job_cond, NULL);
175     pthread_cond_init(&c->last_job_cond,    NULL);
176
177     pthread_mutex_init(&c->current_job_lock, NULL);
178     pthread_mutex_lock(&c->current_job_lock);
179     for (i = 0; i < nb_threads; i++) {
180         ret = pthread_create(&c->workers[i], NULL, worker, c);
181         if (ret) {
182            pthread_mutex_unlock(&c->current_job_lock);
183            c->nb_threads = i;
184            slice_thread_uninit(c);
185            return AVERROR(ret);
186         }
187     }
188
189     slice_thread_park_workers(c);
190
191     return c->nb_threads;
192 }
193
194 int ff_graph_thread_init(AVFilterGraph *graph)
195 {
196     int ret;
197
198 #if HAVE_W32THREADS
199     w32thread_init();
200 #endif
201
202     if (graph->nb_threads == 1) {
203         graph->thread_type = 0;
204         return 0;
205     }
206
207     graph->internal->thread = av_mallocz(sizeof(ThreadContext));
208     if (!graph->internal->thread)
209         return AVERROR(ENOMEM);
210
211     ret = thread_init_internal(graph->internal->thread, graph->nb_threads);
212     if (ret <= 1) {
213         av_freep(&graph->internal->thread);
214         graph->thread_type = 0;
215         graph->nb_threads  = 1;
216         return (ret < 0) ? ret : 0;
217     }
218     graph->nb_threads = ret;
219
220     graph->internal->thread_execute = thread_execute;
221
222     return 0;
223 }
224
225 void ff_graph_thread_free(AVFilterGraph *graph)
226 {
227     if (graph->internal->thread)
228         slice_thread_uninit(graph->internal->thread);
229     av_freep(&graph->internal->thread);
230 }