Bypass JDK-8313796 workaround for the fixed JDK versions (#273)

Author: zhengyu123

ddprof-lib/src/main/cpp/profiler.cpp

@@ -43,6 +43,7 @@
 // can be still accessed concurrently during VM termination
 Profiler *const Profiler::_instance = new Profiler();
 volatile bool Profiler::_signals_initialized = false;
+volatile bool Profiler::_need_JDK_8313796_workaround = true;
 
 static void (*orig_trapHandler)(int signo, siginfo_t *siginfo, void *ucontext);
 static void (*orig_segvHandler)(int signo, siginfo_t *siginfo, void *ucontext);
@@ -917,8 +918,9 @@ bool Profiler::crashHandler(int signo, siginfo_t *siginfo, void *ucontext) {
 
     ddprof::StackWalker::checkFault(thrd);
 
-    // Workaround for JDK-8313796. Setting cstack=dwarf also helps
-    if (VMStructs::isInterpretedFrameValidFunc((const void *)pc) &&
+    // Workaround for JDK-8313796 if needed. Setting cstack=dwarf also helps
+    if (_need_JDK_8313796_workaround &&
+        VMStructs::isInterpretedFrameValidFunc((const void *)pc) &&
         frame.skipFaultInstruction()) {
       if (thrd != nullptr) {
         thrd->exitCrashHandler();
@@ -1101,6 +1103,20 @@ Error Profiler::checkJvmCapabilities() {
   return Error::OK;
 }
 
+void Profiler::check_JDK_8313796_workaround() {
+  int java_version = VM::java_version();
+  int java_update_version = VM::java_update_version();
+
+  // JDK-8313796 has been fixed in JDK 22 and backported to
+  // JDK versions 11.0.21, 17.0.9 and 21.0.1
+  bool fixed_version = java_version >= 22 ||
+                         (java_version == 11 && java_update_version >= 21) ||
+                         (java_version == 17 && java_update_version >= 9) ||
+                         (java_version == 21 && java_update_version >= 1);
+    _need_JDK_8313796_workaround = !fixed_version;
+}
+
+
 Error Profiler::start(Arguments &args, bool reset) {
   MutexLocker ml(_state_lock);
   if (_state > IDLE) {

ddprof-lib/src/main/cpp/profiler.h

@@ -67,6 +67,9 @@ class Profiler {
   // signal handlers
   static volatile bool _signals_initialized;
 
+  // JDK_8313796 workaround for unfixed versions
+  static volatile bool _need_JDK_8313796_workaround;
+
   Mutex _state_lock;
   State _state;
   // class unload hook
@@ -152,6 +155,7 @@ class Profiler {
   void unlockAll();
 
   static bool crashHandler(int signo, siginfo_t *siginfo, void *ucontext);
+  static void check_JDK_8313796_workaround();
 
   static Profiler *const _instance;
 

ddprof-lib/src/main/cpp/vmEntry.cpp

@@ -459,6 +459,7 @@ bool VM::initProfilerBridge(JavaVM *vm, bool attach) {
 
 // Run late initialization when JVM is ready
 void VM::ready(jvmtiEnv *jvmti, JNIEnv *jni) {
+  Profiler::check_JDK_8313796_workaround();
   Profiler::setupSignalHandlers();
   {
     JitWriteProtection jit(true);