From d866fa4c1f3f216f2d4ddab4d2841cf730e07b6f Mon Sep 17 00:00:00 2001
From: Robert Toyonaga <rtoyonag@redhat.com>
Date: Thu, 27 Jun 2024 12:58:19 -0400
Subject: [PATCH 1/2] remove duplicate thread sleep events and use a constant
 clock for JFR chunks

---
 .../src/com/oracle/svm/core/jfr/JfrTicks.java  |  3 ++-
 .../svm/core/thread/PlatformThreads.java       | 18 ++----------------
 2 files changed, 4 insertions(+), 17 deletions(-)

diff --git a/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jfr/JfrTicks.java b/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jfr/JfrTicks.java
index 0c012bfb21e6..f1d13c66e87d 100644
--- a/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jfr/JfrTicks.java
+++ b/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jfr/JfrTicks.java
@@ -26,6 +26,7 @@
 
 import com.oracle.svm.core.Uninterruptible;
 import com.oracle.svm.core.util.TimeUtils;
+import com.oracle.svm.core.util.PlatformTimeUtils;
 
 /**
  * Utility class to manage ticks for event timestamps based on an initial start point when the
@@ -72,6 +73,6 @@ public static long millisToTicks(long millis) {
     }
 
     public static long currentTimeNanos() {
-        return TimeUtils.millisToNanos(System.currentTimeMillis());
+        return PlatformTimeUtils.singleton().nanosNow();
     }
 }
diff --git a/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/PlatformThreads.java b/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/PlatformThreads.java
index 02b739935554..af15dc896ac9 100644
--- a/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/PlatformThreads.java
+++ b/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/PlatformThreads.java
@@ -89,7 +89,6 @@
 import com.oracle.svm.core.heap.VMOperationInfos;
 import com.oracle.svm.core.jdk.StackTraceUtils;
 import com.oracle.svm.core.jdk.UninterruptibleUtils;
-import com.oracle.svm.core.jfr.HasJfrSupport;
 import com.oracle.svm.core.locks.VMMutex;
 import com.oracle.svm.core.log.Log;
 import com.oracle.svm.core.memory.NativeMemory;
@@ -110,7 +109,6 @@
 
 import jdk.graal.compiler.api.replacements.Fold;
 import jdk.graal.compiler.core.common.SuppressFBWarnings;
-import jdk.internal.event.ThreadSleepEvent;
 import jdk.internal.misc.Unsafe;
 
 /**
@@ -983,23 +981,11 @@ static void unpark(Thread thread) {
     }
 
     /**
-     * Sleeps for the given number of nanoseconds, dealing with JFR events, wakups and
-     * interruptions.
+     * Sleeps for the given number of nanoseconds, wake-ups and interruptions.
      */
     static void sleep(long nanos) throws InterruptedException {
         assert !isCurrentThreadVirtual();
-        if (HasJfrSupport.get() && ThreadSleepEvent.isTurnedOn()) {
-            ThreadSleepEvent event = new ThreadSleepEvent();
-            try {
-                event.time = nanos;
-                event.begin();
-                sleep0(nanos);
-            } finally {
-                event.commit();
-            }
-        } else {
-            sleep0(nanos);
-        }
+        sleep0(nanos);
     }
 
     /** Sleep for the given number of nanoseconds, dealing with early wakeups and interruptions. */

From 2caaa38f924760e55668094aa5968192457f0db8 Mon Sep 17 00:00:00 2001
From: Christian Haeubl <christian.haeubl@oracle.com>
Date: Thu, 11 Jul 2024 10:47:21 +0200
Subject: [PATCH 2/2] Cleanups.

---
 .../com/oracle/svm/core/thread/PlatformThreads.java   | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/PlatformThreads.java b/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/PlatformThreads.java
index af15dc896ac9..e8930ec79a07 100644
--- a/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/PlatformThreads.java
+++ b/substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/PlatformThreads.java
@@ -981,25 +981,20 @@ static void unpark(Thread thread) {
     }
 
     /**
-     * Sleeps for the given number of nanoseconds, wake-ups and interruptions.
+     * Sleeps for the given number of nanoseconds, dealing with early wake-ups and interruptions.
      */
     static void sleep(long nanos) throws InterruptedException {
         assert !isCurrentThreadVirtual();
-        sleep0(nanos);
-    }
-
-    /** Sleep for the given number of nanoseconds, dealing with early wakeups and interruptions. */
-    static void sleep0(long nanos) throws InterruptedException {
         if (nanos < 0) {
             throw new IllegalArgumentException("Timeout value is negative");
         }
-        sleep1(nanos);
+        sleep0(nanos);
         if (Thread.interrupted()) { // clears the interrupted flag as required of Thread.sleep()
             throw new InterruptedException();
         }
     }
 
-    private static void sleep1(long durationNanos) {
+    private static void sleep0(long durationNanos) {
         VMOperationControl.guaranteeOkayToBlock("[PlatformThreads.sleep(long): Should not sleep when it is not okay to block.]");
         Thread thread = currentThread.get();
         Parker sleepEvent = getCurrentThreadData().ensureSleepParker();