1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
|
#include <assert.h>
#include <pthread.h>
#include <stdlib.h>
#include "til.h"
#include "til_fb.h"
#include "til_threads.h"
#include "til_util.h"
typedef struct til_thread_t {
til_threads_t *threads;
pthread_t pthread;
unsigned id;
} til_thread_t;
typedef struct til_threads_t {
unsigned n_threads;
pthread_mutex_t idle_mutex;
pthread_cond_t idle_cond;
unsigned idle_n_fragments;
unsigned idle_n_zeroed;
unsigned n_idle;
pthread_mutex_t frame_mutex;
pthread_cond_t frame_cond;
void (*render_fragment_func)(void *context, unsigned ticks, unsigned cpu, til_fb_fragment_t *fragment);
void *context;
til_fb_fragment_t *fragment;
til_fragmenter_t fragmenter;
unsigned ticks;
unsigned next_fragment;
unsigned frame_num;
til_thread_t threads[];
} til_threads_t;
/* render fragments using the supplied render function */
static void * thread_func(void *_thread)
{
til_thread_t *thread = _thread;
til_threads_t *threads = thread->threads;
unsigned prev_frame_num = 0;
pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL);
for (;;) {
unsigned n_fragments = 0, n_zeroed = 0;
/* wait for a new frame */
pthread_mutex_lock(&threads->frame_mutex);
pthread_cleanup_push((void (*)(void *))pthread_mutex_unlock, &threads->frame_mutex);
while (threads->frame_num == prev_frame_num)
pthread_cond_wait(&threads->frame_cond, &threads->frame_mutex);
prev_frame_num = threads->frame_num;
pthread_cleanup_pop(1);
/* render fragments */
for (;;) {
unsigned frag_num;
til_fb_fragment_t fragment;
frag_num = __sync_fetch_and_add(&threads->next_fragment, 1);
if (!threads->fragmenter(threads->context, threads->fragment, frag_num, &fragment))
break;
threads->render_fragment_func(threads->context, threads->ticks, thread->id, &fragment);
n_zeroed += fragment.zeroed;
n_fragments++;
}
/* report as idle */
pthread_mutex_lock(&threads->idle_mutex);
pthread_cleanup_push((void (*)(void *))pthread_mutex_unlock, &threads->idle_mutex);
threads->idle_n_fragments += n_fragments;
threads->idle_n_zeroed += n_zeroed;
threads->n_idle++;
if (threads->n_idle == threads->n_threads) { /* Frame finished! Notify potential waiter. */
if (threads->idle_n_zeroed == threads->idle_n_fragments)
threads->fragment->zeroed = 1;
pthread_cond_signal(&threads->idle_cond);
}
pthread_cleanup_pop(1);
}
return NULL;
}
/* wait for all threads to be idle */
void til_threads_wait_idle(til_threads_t *threads)
{
pthread_mutex_lock(&threads->idle_mutex);
pthread_cleanup_push((void (*)(void *))pthread_mutex_unlock, &threads->idle_mutex);
while (threads->n_idle < threads->n_threads)
pthread_cond_wait(&threads->idle_cond, &threads->idle_mutex);
pthread_cleanup_pop(1);
}
/* submit a frame's fragments to the threads */
void til_threads_frame_submit(til_threads_t *threads, til_fb_fragment_t *fragment, til_fragmenter_t fragmenter, void (*render_fragment_func)(void *context, unsigned ticks, unsigned cpu, til_fb_fragment_t *fragment), void *context, unsigned ticks)
{
til_threads_wait_idle(threads); /* XXX: likely non-blocking; already happens pre page flip */
pthread_mutex_lock(&threads->frame_mutex);
pthread_cleanup_push((void (*)(void *))pthread_mutex_unlock, &threads->frame_mutex);
threads->fragment = fragment;
threads->fragmenter = fragmenter;
threads->render_fragment_func = render_fragment_func;
threads->context = context;
threads->ticks = ticks;
threads->frame_num++;
threads->n_idle = threads->idle_n_zeroed = threads->idle_n_fragments = threads->next_fragment = 0;
pthread_cond_broadcast(&threads->frame_cond);
pthread_cleanup_pop(1);
}
/* create threads instance, a thread per cpu is created */
til_threads_t * til_threads_create(void)
{
unsigned num = til_get_ncpus();
til_threads_t *threads;
threads = calloc(1, sizeof(til_threads_t) + sizeof(til_thread_t) * num);
if (!threads)
return NULL;
threads->n_idle = threads->n_threads = num;
pthread_mutex_init(&threads->idle_mutex, NULL);
pthread_cond_init(&threads->idle_cond, NULL);
pthread_mutex_init(&threads->frame_mutex, NULL);
pthread_cond_init(&threads->frame_cond, NULL);
for (unsigned i = 0; i < num; i++) {
til_thread_t *thread = &threads->threads[i];
thread->threads = threads;
thread->id = i;
pthread_create(&thread->pthread, NULL, thread_func, thread);
}
return threads;
}
/* destroy a threads instance */
void til_threads_destroy(til_threads_t *threads)
{
for (unsigned i = 0; i < threads->n_threads; i++)
pthread_cancel(threads->threads[i].pthread);
for (unsigned i = 0; i < threads->n_threads; i++)
pthread_join(threads->threads[i].pthread, NULL);
pthread_mutex_destroy(&threads->idle_mutex);
pthread_cond_destroy(&threads->idle_cond);
pthread_mutex_destroy(&threads->frame_mutex);
pthread_cond_destroy(&threads->frame_cond);
free(threads);
}
/* return the number of threads */
unsigned til_threads_num_threads(til_threads_t *threads)
{
return threads->n_threads;
}
|