From fbdc1416b0eb3d1c810a03917d7c2cad1fb2dcb1 Mon Sep 17 00:00:00 2001
From: Thomas Schatzl <thomas.schatzl@oracle.com>
Date: Fri, 1 Aug 2025 11:37:15 +0200
Subject: [PATCH 1/2] 8364503

Hi all,

  please review this change to the `gc/g1/TestCodeCacheUnloadDuringConcCycle.java` test - previously, the GC that we were waiting for in the test could occur between releasing whitebox control and the marker we use to distinguish before/after test setup.

The change makes sure the marker is printed before releasing Whitebox control.

Testing:

Thanks,
  Thomas
---
 .../jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java    | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/test/hotspot/jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java b/test/hotspot/jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java
index 94f65a4328f6e..22cfc51ccebee 100644
--- a/test/hotspot/jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java
+++ b/test/hotspot/jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java
@@ -147,6 +147,7 @@ private static void triggerCodeCacheGC() throws Exception {
     }
 
     public static void main(String[] args) throws Exception {
+        System.out.println("Running to breakpoint: " + args[0]);
         try {
             WB.concurrentGCAcquireControl();
             WB.concurrentGCRunTo(args[0]);
@@ -157,9 +158,13 @@ public static void main(String[] args) throws Exception {
 
             WB.concurrentGCRunToIdle();
         } finally {
+            // Make sure that the marker we use to find the expected log message is printed
+            // before we release whitebox control, i.e. before the expected garbage collection
+            // can start.
+            System.out.println(TestCodeCacheUnloadDuringConcCycle.AFTER_FIRST_CYCLE_MARKER);
+            System.out.flush();
             WB.concurrentGCReleaseControl();
         }
-        System.out.println(TestCodeCacheUnloadDuringConcCycle.AFTER_FIRST_CYCLE_MARKER);
         Thread.sleep(1000);
         triggerCodeCacheGC();
     }

From 3ff76be7fa05020fc48c39fa35fa279221ae3f50 Mon Sep 17 00:00:00 2001
From: Thomas Schatzl <thomas.schatzl@oracle.com>
Date: Mon, 4 Aug 2025 09:59:20 +0200
Subject: [PATCH 2/2] * review ayang

---
 test/hotspot/jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/hotspot/jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java b/test/hotspot/jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java
index 22cfc51ccebee..a4fadc185d22d 100644
--- a/test/hotspot/jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java
+++ b/test/hotspot/jtreg/gc/g1/TestCodeCacheUnloadDuringConcCycle.java
@@ -162,7 +162,6 @@ public static void main(String[] args) throws Exception {
             // before we release whitebox control, i.e. before the expected garbage collection
             // can start.
             System.out.println(TestCodeCacheUnloadDuringConcCycle.AFTER_FIRST_CYCLE_MARKER);
-            System.out.flush();
             WB.concurrentGCReleaseControl();
         }
         Thread.sleep(1000);