src/os/solaris/vm/os_solaris.cpp
Print this page
rev 6280 : [mq]: osx-clock
@@ -1393,13 +1393,18 @@
// gethrtime can move backwards if read from one cpu and then a different cpu
// getTimeNanos is guaranteed to not move backward on Solaris
inline hrtime_t getTimeNanos() {
if (VM_Version::supports_cx8()) {
const hrtime_t now = gethrtime();
- // Use atomic long load since 32-bit x86 uses 2 registers to keep long.
- const hrtime_t prev = Atomic::load((volatile jlong*)&max_hrtime);
- if (now <= prev) return prev; // same or retrograde time;
+ if (AssumeMonotonicOSTimers) {
+ return now;
+ }
+
+ const hrtime_t prev = max_hrtime;
+ if (now <= prev) {
+ return prev; // same or retrograde time;
+ }
const hrtime_t obsv = Atomic::cmpxchg(now, (volatile jlong*)&max_hrtime, prev);
assert(obsv >= prev, "invariant"); // Monotonicity
// If the CAS succeeded then we're done and return "now".
// If the CAS failed and the observed value "obs" is >= now then
// we should return "obs". If the CAS failed and now > obs > prv then