From 478ade750e338519bf502e861d91d193d88ddb48 Mon Sep 17 00:00:00 2001
From: Vinoth Veeraraghavan <vinoth.veeraraghavan@hotmail.com>
Date: Tue, 22 Sep 2020 15:42:28 +0800
Subject: [PATCH] Fix bug in JIT source purging: do not nullify attached
 context list after purge

---
 .../storage/mot/jit_exec/src/jit_context.cpp      | 15 ++++++++++++---
 .../storage/mot/jit_exec/src/jit_exec.cpp         |  1 +
 .../storage/mot/jit_exec/src/jit_source.cpp       | 13 +++++++++++--
 3 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/gausskernel/storage/mot/jit_exec/src/jit_context.cpp b/src/gausskernel/storage/mot/jit_exec/src/jit_context.cpp
index bec8addd9..217e871cc 100755
--- a/src/gausskernel/storage/mot/jit_exec/src/jit_context.cpp
+++ b/src/gausskernel/storage/mot/jit_exec/src/jit_context.cpp
@@ -506,19 +506,26 @@ extern void PurgeJitContext(JitContext* jitContext, uint64_t relationId)
 
         // cleanup keys(s)
         if ((jitContext->m_table != nullptr) && (jitContext->m_table->GetTableExId() == relationId)) {
+            MOT_LOG_TRACE("Purging JIT context %p primary keys by relation id %" PRIu64, jitContext, relationId);
             CleanupJitContextPrimary(jitContext);
         }
 
         // cleanup JOIN keys(s)
         if ((jitContext->m_innerTable != nullptr) && (jitContext->m_innerTable->GetTableExId() == relationId)) {
+            MOT_LOG_TRACE("Purging JIT context %p inner keys by relation id %" PRIu64, jitContext, relationId);
             CleanupJitContextInner(jitContext);
         }
 
         // cleanup sub-query keys
         for (uint32_t i = 0; i < jitContext->m_subQueryCount; ++i) {
             JitContext::SubQueryData* subQueryData = &jitContext->m_subQueryData[i];
-            MOT_LOG_TRACE("Cleaning up sub-query %u data in JIT context %p", i, jitContext);
-            CleanupJitContextSubQueryData(subQueryData);
+            if ((subQueryData->m_table != nullptr) && (subQueryData->m_table->GetTableExId() == relationId)) {
+                MOT_LOG_TRACE("Purging sub-query %u data in JIT context %p by relation id %" PRIu64,
+                    i,
+                    jitContext,
+                    relationId);
+                CleanupJitContextSubQueryData(subQueryData);
+            }
         }
     }
 }
@@ -564,7 +571,9 @@ static void CleanupJitContextInner(JitContext* jitContext)
 
 static void CleanupJitContextSubQueryDataArray(JitContext* jitContext)
 {
-    MOT_LOG_TRACE("Cleaning up sub-query data array in JIT context %p", jitContext);
+    if (jitContext->m_subQueryData != nullptr) {
+        MOT_LOG_TRACE("Cleaning up sub-query data array in JIT context %p", jitContext);
+    }
     for (uint32_t i = 0; i < jitContext->m_subQueryCount; ++i) {
         JitContext::SubQueryData* subQueryData = &jitContext->m_subQueryData[i];
         MOT_LOG_TRACE("Cleaning up sub-query %u data in JIT context %p", i, jitContext);
diff --git a/src/gausskernel/storage/mot/jit_exec/src/jit_exec.cpp b/src/gausskernel/storage/mot/jit_exec/src/jit_exec.cpp
index 915a66b45..6b56caf55 100644
--- a/src/gausskernel/storage/mot/jit_exec/src/jit_exec.cpp
+++ b/src/gausskernel/storage/mot/jit_exec/src/jit_exec.cpp
@@ -452,6 +452,7 @@ extern int JitExecQuery(
 
 extern void PurgeJitSourceCache(uint64_t relationId)
 {
+    MOT_LOG_TRACE("Purging JIT source map by relation id %" PRIu64, relationId);
     (void)PurgeJitSourceMap(relationId);
 }
 
diff --git a/src/gausskernel/storage/mot/jit_exec/src/jit_source.cpp b/src/gausskernel/storage/mot/jit_exec/src/jit_source.cpp
index 23423d661..8da7a2e09 100644
--- a/src/gausskernel/storage/mot/jit_exec/src/jit_source.cpp
+++ b/src/gausskernel/storage/mot/jit_exec/src/jit_source.cpp
@@ -84,9 +84,18 @@ extern bool InitJitSource(JitSource* jitSource, const char* queryString)
 extern void DestroyJitSource(JitSource* jitSource)
 {
     MOT_LOG_TRACE("Destroying JIT source %p with query string: %s", jitSource, jitSource->_query_string);
+    if (jitSource->m_contextList != nullptr) {
+        MOT_LOG_WARN("JIT source still contains registered JIT context objects, while destroying JIT source");
+        JitContext* jitContext = jitSource->m_contextList;
+        while (jitContext != nullptr) {
+            jitContext->m_jitSource = nullptr;  // prevent crash during DestroyJitContext()
+            jitContext = jitContext->m_nextInSource;
+        }
+    }
+
     if (jitSource->_source_jit_context != nullptr) {
         // this code is executed during shutdown, so the underlying
-        // GsCodeGen object was already destroyed the top memory context
+        // GsCodeGen object was already destroyed by the top memory context
         DestroyJitContext(jitSource->_source_jit_context);
         jitSource->_source_jit_context = NULL;
     }
@@ -288,6 +297,7 @@ static void SetJitSourceStatus(JitSource* jitSource, JitContext* readySourceJitC
             }
             jitSource->m_contextList = nullptr;
         } else {  // expired context: cleanup all related JIT context objects
+            MOT_LOG_TRACE("Purging all JIT context objects by relation id %" PRIu64, relationId);
             JitSourcePurgeContextList(jitSource, relationId);
         }
     }
@@ -344,7 +354,6 @@ static void JitSourcePurgeContextList(JitSource* jitSource, uint64_t relationId)
         PurgeJitContext(itr, relationId);
         itr = itr->m_nextInSource;
     }
-    jitSource->m_contextList = nullptr;
 }
 
 static void RemoveJitSourceContextImpl(JitSource* jitSource, JitContext* jitContext)