static void *vsync_loop(void *param)
{
const char* vsync_timestamp_fb0 = "/sys/class/graphics/fb0/vsync_event";
const char* vsync_timestamp_fb1 = "/sys/class/graphics/fb1/vsync_event";
int dpy = HWC_DISPLAY_PRIMARY;
hwc_context_t * ctx = reinterpret_cast<hwc_context_t *>(param);
char thread_name[64] = HWC_VSYNC_THREAD_NAME;
prctl(PR_SET_NAME, (unsigned long) &thread_name, 0, 0, 0);
androidSetThreadPriority(0, HAL_PRIORITY_URGENT_DISPLAY +
android::PRIORITY_MORE_FAVORABLE);
android_set_rt_ioprio(0, 1);
const int MAX_DATA = 64;
static char vdata[MAX_DATA];
uint64_t cur_timestamp=0;
ssize_t len = -1;
int fd_timestamp = -1;
int ret = 0;
bool fb1_vsync = false;
bool logvsync = false;
char property[PROPERTY_VALUE_MAX];
if(property_get("debug.hwc.fakevsync", property, NULL) > 0) {
if(atoi(property) == 1)
ctx->vstate.fakevsync = true;
}
if(property_get("debug.hwc.logvsync", property, 0) > 0) {
if(atoi(property) == 1)
logvsync = true;
}
/* Currently read vsync timestamp from drivers
e.g. VSYNC=41800875994
*/
fd_timestamp = open(vsync_timestamp_fb0, O_RDONLY);
if (fd_timestamp < 0) {
// Make sure fb device is opened before starting this thread so this
// never happens.
ALOGE ("FATAL:%s:not able to open file:%s, %s", __FUNCTION__,
(fb1_vsync) ? vsync_timestamp_fb1 : vsync_timestamp_fb0,
strerror(errno));
ctx->vstate.fakevsync = true;
}
do {
if (LIKELY(!ctx->vstate.fakevsync)) {
len = pread(fd_timestamp, vdata, MAX_DATA, 0);
if (len < 0) {
// If the read was just interrupted - it is not a fatal error
// In either case, just continue.
if (errno != EAGAIN &&
errno != EINTR &&
errno != EBUSY) {
ALOGE ("FATAL:%s:not able to read file:%s, %s",
__FUNCTION__,
vsync_timestamp_fb0, strerror(errno));
}
continue;
}
// extract timestamp
const char *str = vdata;
if (!strncmp(str, "VSYNC=", strlen("VSYNC="))) {
cur_timestamp = strtoull(str + strlen("VSYNC="), NULL, 0);
}
} else {
usleep(16666);
cur_timestamp = systemTime();
}
// send timestamp to HAL
if(ctx->vstate.enable) {
ALOGD_IF (logvsync, "%s: timestamp %llu sent to HWC for %s",
__FUNCTION__, cur_timestamp, "fb0");
ctx->proc->vsync(ctx->proc, dpy, cur_timestamp);
}
} while (true);
if(fd_timestamp >= 0)
close (fd_timestamp);
return NULL;
}
void EventThread::onFirstRef() {
run("EventThread", PRIORITY_URGENT_DISPLAY + PRIORITY_MORE_FAVORABLE);
android_set_rt_ioprio(getTid(), 1);
}