diff src/os/linux/vm/os_linux.hpp @ 12211:2e6938dd68f2

6900441: PlatformEvent.park(millis) on Linux could still be affected by changes to the time-of-day clock Summary: Associate CLOCK_MONOTONIC with the pthread_cond_t objects used for relative timed waits Reviewed-by: dcubed, shade
author dholmes
date Mon, 16 Sep 2013 07:38:13 -0400
parents 0d59407e7e09
children b0133e4187d3 6c9332549827
line wrap: on
line diff
--- a/src/os/linux/vm/os_linux.hpp	Fri Sep 13 16:56:58 2013 -0700
+++ b/src/os/linux/vm/os_linux.hpp	Mon Sep 16 07:38:13 2013 -0400
@@ -221,6 +221,13 @@
 
   static jlong fast_thread_cpu_time(clockid_t clockid);
 
+  // pthread_cond clock suppport
+  private:
+  static pthread_condattr_t _condattr[1];
+
+  public:
+  static pthread_condattr_t* condAttr() { return _condattr; }
+
   // Stack repair handling
 
   // none present
@@ -295,7 +302,7 @@
   public:
     PlatformEvent() {
       int status;
-      status = pthread_cond_init (_cond, NULL);
+      status = pthread_cond_init (_cond, os::Linux::condAttr());
       assert_status(status == 0, status, "cond_init");
       status = pthread_mutex_init (_mutex, NULL);
       assert_status(status == 0, status, "mutex_init");
@@ -310,14 +317,19 @@
     void park () ;
     void unpark () ;
     int  TryPark () ;
-    int  park (jlong millis) ;
+    int  park (jlong millis) ; // relative timed-wait only
     void SetAssociation (Thread * a) { _Assoc = a ; }
 } ;
 
 class PlatformParker : public CHeapObj<mtInternal> {
   protected:
+    enum {
+        REL_INDEX = 0,
+        ABS_INDEX = 1
+    };
+    int _cur_index;  // which cond is in use: -1, 0, 1
     pthread_mutex_t _mutex [1] ;
-    pthread_cond_t  _cond  [1] ;
+    pthread_cond_t  _cond  [2] ; // one for relative times and one for abs.
 
   public:       // TODO-FIXME: make dtor private
     ~PlatformParker() { guarantee (0, "invariant") ; }
@@ -325,10 +337,13 @@
   public:
     PlatformParker() {
       int status;
-      status = pthread_cond_init (_cond, NULL);
-      assert_status(status == 0, status, "cond_init");
+      status = pthread_cond_init (&_cond[REL_INDEX], os::Linux::condAttr());
+      assert_status(status == 0, status, "cond_init rel");
+      status = pthread_cond_init (&_cond[ABS_INDEX], NULL);
+      assert_status(status == 0, status, "cond_init abs");
       status = pthread_mutex_init (_mutex, NULL);
       assert_status(status == 0, status, "mutex_init");
+      _cur_index = -1; // mark as unused
     }
 };