void
ThreadMain(void*)
{
PR_SetCurrentThreadName("Hang Monitor");
MonitorAutoLock lock(*gMonitor);
// In order to avoid issues with the hang monitor incorrectly triggering
// during a general system stop such as sleeping, the monitor thread must
// run twice to trigger hang protection.
PRIntervalTime lastTimestamp = 0;
int waitCount = 0;
#ifdef REPORT_CHROME_HANGS
Telemetry::ProcessedStack stack;
int32_t systemUptime = -1;
int32_t firefoxUptime = -1;
auto annotations = MakeUnique<ChromeHangAnnotations>();
#endif
while (true) {
if (gShutdown) {
return; // Exit the thread
}
// avoid rereading the volatile value in this loop
PRIntervalTime timestamp = gTimestamp;
PRIntervalTime now = PR_IntervalNow();
if (timestamp != PR_INTERVAL_NO_WAIT &&
now < timestamp) {
// 32-bit overflow, reset for another waiting period
timestamp = 1; // lowest legal PRInterval value
}
if (timestamp != PR_INTERVAL_NO_WAIT &&
timestamp == lastTimestamp &&
gTimeout > 0) {
++waitCount;
#ifdef REPORT_CHROME_HANGS
// Capture the chrome-hang stack + Firefox & system uptimes after
// the minimum hang duration has been reached (not when the hang ends)
if (waitCount == 2) {
GetChromeHangReport(stack, systemUptime, firefoxUptime);
ChromeHangAnnotatorCallout(*annotations);
}
#else
// This is the crash-on-hang feature.
// See bug 867313 for the quirk in the waitCount comparison
if (waitCount >= 2) {
int32_t delay =
int32_t(PR_IntervalToSeconds(now - timestamp));
if (delay >= gTimeout) {
MonitorAutoUnlock unlock(*gMonitor);
Crash();
}
}
#endif
} else {
#ifdef REPORT_CHROME_HANGS
if (waitCount >= 2) {
uint32_t hangDuration = PR_IntervalToSeconds(now - lastTimestamp);
Telemetry::RecordChromeHang(hangDuration, stack, systemUptime,
firefoxUptime, Move(annotations));
stack.Clear();
annotations = MakeUnique<ChromeHangAnnotations>();
}
#endif
lastTimestamp = timestamp;
waitCount = 0;
}
PRIntervalTime timeout;
if (gTimeout <= 0) {
timeout = PR_INTERVAL_NO_TIMEOUT;
} else {
timeout = PR_MillisecondsToInterval(gTimeout * 500);
}
lock.Wait(timeout);
}
}
void
ThreadMain(void*)
{
PR_SetCurrentThreadName("Hang Monitor");
MonitorAutoLock lock(*gMonitor);
// In order to avoid issues with the hang monitor incorrectly triggering
// during a general system stop such as sleeping, the monitor thread must
// run twice to trigger hang protection.
PRIntervalTime lastTimestamp = 0;
int waitCount = 0;
#ifdef REPORT_CHROME_HANGS
Telemetry::ProcessedStack stack;
#endif
while (true) {
if (gShutdown) {
return; // Exit the thread
}
// avoid rereading the volatile value in this loop
PRIntervalTime timestamp = gTimestamp;
PRIntervalTime now = PR_IntervalNow();
if (timestamp != PR_INTERVAL_NO_WAIT &&
now < timestamp) {
// 32-bit overflow, reset for another waiting period
timestamp = 1; // lowest legal PRInterval value
}
if (timestamp != PR_INTERVAL_NO_WAIT &&
timestamp == lastTimestamp &&
gTimeout > 0) {
++waitCount;
if (waitCount == 2) {
#ifdef REPORT_CHROME_HANGS
GetChromeHangReport(stack);
#else
int32_t delay =
int32_t(PR_IntervalToSeconds(now - timestamp));
if (delay > gTimeout) {
MonitorAutoUnlock unlock(*gMonitor);
Crash();
}
#endif
}
}
else {
#ifdef REPORT_CHROME_HANGS
if (waitCount >= 2) {
uint32_t hangDuration = PR_IntervalToSeconds(now - lastTimestamp);
Telemetry::RecordChromeHang(hangDuration, stack);
stack.Clear();
}
#endif
lastTimestamp = timestamp;
waitCount = 0;
}
PRIntervalTime timeout;
if (gTimeout <= 0) {
timeout = PR_INTERVAL_NO_TIMEOUT;
}
else {
timeout = PR_MillisecondsToInterval(gTimeout * 500);
}
lock.Wait(timeout);
}
}