From ed68337235e5438c146828888fcf6dda3bb44a8b Mon Sep 17 00:00:00 2001
From: Irwin D'Souza <dsouzai.gh@gmail.com>
Date: Tue, 14 Jan 2025 11:36:10 -0500
Subject: [PATCH] Close and Reopen log files across a checkpoint/restore

A common best practice in CRIU mode, at least in OpenJ9, is to close all
open files before a checkpoint, and reopen them on restore. The JIT
would keep log files such as the vlog and rtLog open across a
checkpoint/restore boundary. This commit closes these files on
checkpoint and reopens them on restore.

Signed-off-by: Irwin D'Souza <dsouzai.gh@gmail.com>
---
 runtime/compiler/runtime/CRRuntime.cpp | 61 ++++++++++++++++++++++++++
 runtime/compiler/runtime/CRRuntime.hpp | 10 +++++
 2 files changed, 71 insertions(+)

diff --git a/runtime/compiler/runtime/CRRuntime.cpp b/runtime/compiler/runtime/CRRuntime.cpp
index 2af1a3857e2..d7119984604 100644
--- a/runtime/compiler/runtime/CRRuntime.cpp
+++ b/runtime/compiler/runtime/CRRuntime.cpp
@@ -40,6 +40,7 @@
 #include "infra/Assert.hpp"
 #include "infra/CriticalSection.hpp"
 #include "infra/Monitor.hpp"
+#include "runtime/CodeRuntime.hpp"
 #include "runtime/CRRuntime.hpp"
 #include "runtime/IProfiler.hpp"
 #include "runtime/J9VMAccess.hpp"
@@ -677,6 +678,62 @@ TR::CRRuntime::resetStartTime()
    _restoreTime = persistentInfo->getElapsedTime();
    }
 
+void
+TR::CRRuntime::closeLogFiles()
+   {
+   TR_JitPrivateConfig *privateConfig = (TR_JitPrivateConfig*)getJITConfig()->privateConfig;
+
+   if (privateConfig->vLogFileName)
+      {
+      TR_VerboseLog::vlogAcquire();
+      j9jit_fclose(privateConfig->vLogFile);
+      privateConfig->vLogFile = NULL;
+      TR_VerboseLog::vlogRelease();
+      }
+
+   if (privateConfig->rtLogFileName)
+      {
+      JITRT_LOCK_LOG(getJITConfig());
+      j9jit_fclose(privateConfig->rtLogFile);
+      privateConfig->rtLogFile = NULL;
+      JITRT_UNLOCK_LOG(getJITConfig());
+
+      TR::CompilationInfoPerThread * const * arrayOfCompInfoPT = getCompInfo()->getArrayOfCompilationInfoPerThread();
+      for (int32_t i = 0; i < getCompInfo()->getNumTotalAllocatedCompilationThreads(); i++)
+         {
+         TR::CompilationInfoPerThread *compThreadInfoPT = arrayOfCompInfoPT[i];
+         compThreadInfoPT->closeRTLogFile();
+         }
+      }
+   }
+
+void
+TR::CRRuntime::reopenLogFiles()
+   {
+   TR_JitPrivateConfig *privateConfig = (TR_JitPrivateConfig*)getJITConfig()->privateConfig;
+
+   if (privateConfig->vLogFileName)
+      {
+      TR_VerboseLog::vlogAcquire();
+      privateConfig->vLogFile = fileOpen(TR::Options::getCmdLineOptions(), getJITConfig(), privateConfig->vLogFileName, "wb", true);
+      TR_VerboseLog::vlogRelease();
+      }
+
+   if (privateConfig->rtLogFileName)
+      {
+      JITRT_LOCK_LOG(getJITConfig());
+      privateConfig->rtLogFile = fileOpen(TR::Options::getCmdLineOptions(), getJITConfig(), privateConfig->rtLogFileName, "wb", true);
+      JITRT_UNLOCK_LOG(getJITConfig());
+
+      TR::CompilationInfoPerThread * const * arrayOfCompInfoPT = getCompInfo()->getArrayOfCompilationInfoPerThread();
+      for (int32_t i = 0; i < getCompInfo()->getNumTotalAllocatedCompilationThreads(); i++)
+         {
+         TR::CompilationInfoPerThread *compThreadInfoPT = arrayOfCompInfoPT[i];
+         compThreadInfoPT->openRTLogFile();
+         }
+      }
+   }
+
 void
 TR::CRRuntime::prepareForCheckpoint()
    {
@@ -751,6 +808,8 @@ TR::CRRuntime::prepareForCheckpoint()
 
    if (TR::Options::getCmdLineOptions()->getVerboseOption(TR_VerboseCheckpointRestore))
       TR_VerboseLog::writeLineLocked(TR_Vlog_CHECKPOINT_RESTORE, "Ready for checkpoint");
+
+   closeLogFiles();
    }
 
 void
@@ -762,6 +821,8 @@ TR::CRRuntime::prepareForRestore()
    PORT_ACCESS_FROM_JAVAVM(vm);
    OMRPORT_ACCESS_FROM_J9PORT(PORTLIB);
 
+   reopenLogFiles();
+
    if (TR::Options::getCmdLineOptions()->getVerboseOption(TR_VerboseCheckpointRestore))
       TR_VerboseLog::writeLineLocked(TR_Vlog_CHECKPOINT_RESTORE, "Preparing for restore");
 
diff --git a/runtime/compiler/runtime/CRRuntime.hpp b/runtime/compiler/runtime/CRRuntime.hpp
index 22da6bceba0..fc06d2ee4d9 100644
--- a/runtime/compiler/runtime/CRRuntime.hpp
+++ b/runtime/compiler/runtime/CRRuntime.hpp
@@ -347,6 +347,16 @@ class CRRuntime
     */
    void resetStartTime();
 
+   /**
+    * @brief Closes various log files
+    */
+   void closeLogFiles();
+
+   /**
+    * @brief Reopens log files closed at checkpoint
+    */
+   void reopenLogFiles();
+
    /**
     * @brief Helper method to push a J9Method onto the front of list that is
     *        used to memoize a future compilation of said J9Method. This method