Re: RFR(M): 8201375: Add the AllowArchivingWithJavaAgent diagnostic vm option to allow the use of the -javaagent option during CDS dumping

[serguei.spit...@oracle.com]

Hi Calvin, It seems the option name AllowArchivingWithJavaAgent is not right. In fact, it is about JVMTI (native) agents: // Create agents for -agentlib: -agentpath: and converted -Xrun // Invokes Agent_OnLoad // Called very early -- before JavaThreads exist void Threads::create_vm_init_agents() { + if (DumpSharedSpaces && !AllowArchivingWithJavaAgent) { + vm_exit_during_cds_dumping( + "Must enable AllowArchivingWithJavaAgent in order to run Java agent during CDS dumping"); + } extern struct JavaVM_ main_vm; AgentLibrary* agent; JvmtiExport::enter_onload_phase(); for (agent = Arguments::agents(); agent != NULL; agent = agent->next()) { + // CDS dumping does not support native JVMTI agent + if (DumpSharedSpaces && !agent->is_instrument_lib()) { + vm_exit_during_cds_dumping("CDS dumping does not support native JVMTI agent, name", agent->name()); + } + OnLoadEntry_t _on_load_entry_ = lookup_agent_on_load(agent); The flags -agentlib and -agentpath are to run JVMTI (native) agents, and Agent_OnLoad is an entrypoint in native agent library. So, I'm thinking if it'd make sense to rename the option to something like below:   AllowArchivingWithJVMTIAgent or   AllowArchivingWithNativeAgent or   AllowArchivingWithAgent http://cr.openjdk.java.net/%7Eccheung/8201375/webrev.00/src/hotspot/share/memory/filemap.cpp.frames.html 212 _allow_archiving_with_java_agent = AllowArchivingWithJavaAgent; ... 1350 if (_allow_archiving_with_java_agent && !AllowArchivingWithJavaAgent) { 1351 FileMapInfo::fail_continue("The setting of the AllowArchivingWithJavaAgent is different " 1352 "from the setting in the shared archive."); 1353 return false; 1354 } The _allow_archiving_with_java_agent is initialized with the AllowArchivingWithJavaAgent at line 212. It is not clear from scratch how these two values can be different at line 1350. At least, some comment explaining it is needed. Thanks, Serguei On 11/15/18 10:56, Jiangli Zhou wrote: +1 Adding serviceability-dev mailing list. It would be good to have this reviewed by the JVMTI experts also to make sure all cases are covered. Thanks, Jiangli On 11/15/18 9:29 AM, Ioi Lam wrote: Hi Calvin, The changes look good. Thanks - Ioi On 11/14/18 4:40 PM, Calvin Cheung wrote: bug: https://bugs.openjdk.java.net/browse/JDK-8201375 webrev: http://cr.openjdk.java.net/~ccheung/8201375/webrev.00/ This change is for adding a diagnostic vm option (AllowArchivingWithJavaAgent) to allow the -javaagent in the command line during CDS dumping. Please refer to the corresponding CSR (https://bugs.openjdk.java.net/browse/JDK-8213813) for details. Testing: ran hs-tier{1,2,3} tests through mach5. thanks, Calvin