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sched: try to detect also forward time jumps

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This commit is contained in:
Miroslav Lichvar 2014-05-30 17:30:02 +02:00
parent 44c9744d69
commit a3e60c93da
1 changed files with 25 additions and 21 deletions
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38
sched.c
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@ -529,30 +529,33 @@ handle_slew(struct timeval *raw,
/* ================================================== */
/* Try to handle unexpected backward time jump */
#define JUMP_DETECT_THRESHOLD 10
static void
recover_backjump(struct timeval *raw, struct timeval *cooked, int timeout)
static int
check_current_time(struct timeval *raw, int timeout)
{
double diff, err;
double diff;
UTI_DiffTimevalsToDouble(&diff, &last_select_ts_raw, raw);
if (n_timer_queue_entries > 0) {
UTI_DiffTimevalsToDouble(&err, &(timer_queue.next->tv), &last_select_ts_raw);
if (last_select_ts_raw.tv_sec > raw->tv_sec + JUMP_DETECT_THRESHOLD) {
LOG(LOGS_WARN, LOGF_Scheduler, "Backward time jump detected!");
} else if (n_timer_queue_entries > 0 &&
timer_queue.next->tv.tv_sec + JUMP_DETECT_THRESHOLD < raw->tv_sec) {
LOG(LOGS_WARN, LOGF_Scheduler, "Forward time jump detected!");
} else {
err = 0.0;
return 1;
}
diff += err;
if (timeout) {
err = 1.0;
assert(n_timer_queue_entries > 0);
UTI_DiffTimevalsToDouble(&diff, &timer_queue.next->tv, raw);
} else {
UTI_DiffTimevalsToDouble(&diff, &last_select_ts_raw, raw);
}
LOG(LOGS_WARN, LOGF_Scheduler, "Backward time jump detected! (correction %.1f +- %.1f seconds)", diff, err);
/* Cooked time may no longer be valid after dispatching the handlers */
LCL_NotifyExternalTimeStep(raw, raw, diff, fabs(diff));
LCL_NotifyExternalTimeStep(raw, cooked, diff, err);
return 0;
}
/* ================================================== */
@ -600,9 +603,10 @@ SCH_MainLoop(void)
LCL_ReadRawTime(&now);
LCL_CookTime(&now, &cooked, &err);
/* Check if time didn't jump backwards */
if (last_select_ts_raw.tv_sec > now.tv_sec + 1) {
recover_backjump(&now, &cooked, status == 0);
/* Check if the time didn't jump unexpectedly */
if (!check_current_time(&now, status == 0)) {
/* Cook the time again after handling the step */
LCL_CookTime(&now, &cooked, &err);
}
last_select_ts_raw = now;