Hi Could you please review the the fix that add locks information into SA jhsdb stack --mixed output.
Here is the motivation for this rfe and explanation why I add it into SA now. The information about current owners of Hotspot Mutex is often very useful for dealock investigations. The jcmd usually doesn't work because VM can't reach or exit safepoints. So it doesn't respond to jcmd. The SA 'jstack --mixed' provides information about stacktraces on Java and non-Java Threads. So having information about locks along with stack traces might significantly help to identify issues. The gdb allows to provide stacktraces, but the debug symbols are required to get info about locks. These symbols are often absent during execution. Also the debugger solution is OS specifc. The significant part of fix is refacotorrng of mutex_array to be vmStructs compatible. The adding support of non-JavaThreads into SA might be implemented later to obtain more info about their names. The example of output: [2024-11-06T21:32:48.897414435Z] Gathering output for process 1620563 Attaching to process ID 1620533, please wait... Debugger attached successfully. Server compiler detected. JVM version is 24-internal-adhoc.lmesnik.open Deadlock Detection: No deadlocks found. Internal VM Mutex Threads_lock is owned by Unknnown thread (Might be non-Java Thread) with address: 0x00007f8cf825b190 Internal VM Mutex Compile_lock is owned by LockerThread with address: 0x00007f8cf8309a00 ----------------- 1620559 ----------------- "C1 CompilerThread4" https://github.com/openjdk/jdk/pull/28 daemon prio=9 tid=0x00007f8c300566a0 nid=1620559 runnable [0x0000000000000000] java.lang.Thread.State: RUNNABLE JavaThread state: _thread_blocked 0x00007f8cff11e88d syscall + 0x1d 0x00007f8cfe6c99de LinuxWaitBarrier::wait(int) + 0x8e 0x00007f8cfe2be409 SafepointMechanism::process(JavaThread*, bool, bool) + 0x79 0x00007f8cfd53ea91 ThreadInVMfromNative::ThreadInVMfromNative(JavaThread*) + 0xc1 0x00007f8cfd534a00 ciEnv::cache_jvmti_state() + 0x30 0x00007f8cfd679614 CompileBroker::invoke_compiler_on_method(CompileTask*) + 0x204 0x00007f8cfd67adc8 CompileBroker::compiler_thread_loop() + 0x5c8 0x00007f8cfdb4426c JavaThread::thread_main_inner() + 0xcc 0x00007f8cfe5a0bbe Thread::call_run() + 0xbe 0x00007f8cfe16813b thread_native_entry(Thread*) + 0x12b ..... ----------------- 1620554 ----------------- "LockerThread" https://github.com/openjdk/jdk/pull/31 prio=5 tid=0x00007f8cf8309a00 nid=1620554 waiting on condition [0x00007f8cc1dfe000] java.lang.Thread.State: RUNNABLE JavaThread state: _thread_blocked 0x00007f8cff091117 __GI___futex_abstimed_wait_cancelable64 + 0xe7 0x00007f8cff093a41 __GI___pthread_cond_wait + 0x211 ------------- Commit messages: - fix Changes: https://git.openjdk.org/jdk/pull/22171/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=22171&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8343741 Stats: 452 lines in 14 files changed: 379 ins; 69 del; 4 mod Patch: https://git.openjdk.org/jdk/pull/22171.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/22171/head:pull/22171 PR: https://git.openjdk.org/jdk/pull/22171
