src/hotspot/share/jfr/periodic/sampling/jfrThreadSampler.cpp

*** 1,7 ****
  /*
!  * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
--- 1,7 ----
  /*
!  * Copyright (c) 2012, 2019, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
*** 445,454 ****
--- 445,478 ----
  
  static jlong get_monotonic_ms() {
    return os::javaTimeNanos() / 1000000;
  }
  
+ // calculate next sleep period so that it doesn't overflow
+ static jlong calc_next(jlong interval, jlong last_ms, jlong now_ms) {
+     assert(last_ms > 0, "invariant");
+ 
+     jlong time_diff = last_ms - now_ms;
+     jlong next;
+     if (interval == 0) {
+       next = (time_diff < 0) ? (max_jlong + time_diff) : max_jlong;
+     } else {
+       jlong max_v = MAX2<jlong>(interval, 10);
+ 
+       if (time_diff > 0) {
+         if (max_v <= (max_jlong - time_diff)) {
+           next = max_v + time_diff;
+         } else {
+           next = max_jlong;
+         }
+       } else {
+         next = max_v + time_diff;
+       }
+     }
+     return next;
+ }
+ 
  void JfrThreadSampler::run() {
    assert(_sampler_thread == NULL, "invariant");
  
    _sampler_thread = this;
  
*** 460,476 ****
        _sample.wait();
        last_java_ms = get_monotonic_ms();
        last_native_ms = last_java_ms;
      }
      _sample.signal();
-     jlong java_interval = _interval_java == 0 ? max_jlong : MAX2<jlong>(_interval_java, 10);
-     jlong native_interval = _interval_native == 0 ? max_jlong : MAX2<jlong>(_interval_native, 10);
- 
      jlong now_ms = get_monotonic_ms();
  
!     jlong next_j = java_interval + last_java_ms - now_ms;
!     jlong next_n = native_interval + last_native_ms - now_ms;
  
      jlong sleep_to_next = MIN2<jlong>(next_j, next_n);
  
      if (sleep_to_next > 0) {
        os::naked_short_sleep(sleep_to_next);
--- 484,497 ----
        _sample.wait();
        last_java_ms = get_monotonic_ms();
        last_native_ms = last_java_ms;
      }
      _sample.signal();
      jlong now_ms = get_monotonic_ms();
  
!     jlong next_j = calc_next(_interval_java, last_java_ms, now_ms);
!     jlong next_n = calc_next(_interval_native, last_native_ms, now_ms);
  
      jlong sleep_to_next = MIN2<jlong>(next_j, next_n);
  
      if (sleep_to_next > 0) {
        os::naked_short_sleep(sleep_to_next);