If `Agent_OnAttach()` in JVMTI agent which is attempted to load via JVMTI.agent_load dcmd is failed, it would not be unloaded. We've [discussed it on serviceability-dev](https://mail.openjdk.java.net/pipermail/serviceability-dev/2020-September/032839.html). This PR is a continuation of that.
This PR also includes to call `Agent_OnUnload()` when `Agent_OnAttach()` failed. How to reproduce: 1. Build JVMTI agent for test $ git clone https://github.com/YaSuenag/jvmti-examples.git $ cd jvmti-examples/helloworld/out/build $ cmake ../.. 2. Run JShell 3. Load JVMTI agent via `jcmd <PID> JVMTI.agent_load` with "error" ("error" means `Agent_OnAttach()` returns JNI_ERR) $ jcmd 89456 jdk.jshell.execution.RemoteExecutionControl 45651 89547 sun.tools.jcmd.JCmd 89436 jdk.jshell/jdk.internal.jshell.tool.JShellToolProvider $ jcmd 89436 JVMTI.agent_load `pwd`/libhelloworld.so error 89436: return code: -1 4. Check loaded libraries via `jcmd <PID> VM.dynlibs` $ jcmd 89436 VM.dynlibs | grep libhelloworld 7f2f8b06b000-7f2f8b06c000 r--p 00000000 fd:00 11818202 /home/ysuenaga/github/jvmti-examples/helloworld/out/build/libhelloworld.so 7f2f8b06c000-7f2f8b06d000 r-xp 00001000 fd:00 11818202 /home/ysuenaga/github/jvmti-examples/helloworld/out/build/libhelloworld.so 7f2f8b06d000-7f2f8b06e000 r--p 00002000 fd:00 11818202 /home/ysuenaga/github/jvmti-examples/helloworld/out/build/libhelloworld.so 7f2f8b06e000-7f2f8b06f000 r--p 00002000 fd:00 11818202 /home/ysuenaga/github/jvmti-examples/helloworld/out/build/libhelloworld.so 7f2f8b06f000-7f2f8b070000 rw-p 00003000 fd:00 11818202 /home/ysuenaga/github/jvmti-examples/helloworld/out/build/libhelloworld.so ------------- Commit messages: - JVMTI agent is not unloaded when Agent_OnAttach is failed Changes: https://git.openjdk.java.net/jdk/pull/19/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=19&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8252657 Stats: 44 lines in 4 files changed: 32 ins; 6 del; 6 mod Patch: https://git.openjdk.java.net/jdk/pull/19.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/19/head:pull/19 PR: https://git.openjdk.java.net/jdk/pull/19
