May 2023 - hotspot-jfr-dev

RFR: 8307738: JFR: EventStream.openRepository() drops events
by Erik Gahlin 24 May '23

24 May '23

Could I have a review of a fix that prevents events to be dropped in case an end time has been set for a stream. Testing: jdk/jdk/jfr Thanks Erik ------------- Commit messages: - Initial Changes: https://git.openjdk.org/jdk/pull/14103/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=14103&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8307738 Stats: 18 lines in 2 files changed: 9 ins; 2 del; 7 mod Patch: https://git.openjdk.org/jdk/pull/14103.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/14103/head:pull/14103 PR: https://git.openjdk.org/jdk/pull/14103

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RFR: 8307298: JFR: Ensure jdk.jfr.internal.TypeLibrary is initialized only once
by Robert Toyonaga 11 May '23

11 May '23

Hello, may I have a review of a small change that enforces that `jdk.jfr.internal.TypeLibrary` only gets initialized once? Previously, it was the case that `TypeLibrary` was only initialized once, but since [this change](https://github.com/openjdk/jdk/pull/12884/files) it can now be initialized multiple times. This can be a problem because re-initialization [results in attempting to add elements to `jdk.jfr.internal.Type#fields`](https://github.com/openjdk/jdk/blob/master/src/jdk.jfr/share/classes/jdk/jfr/internal/MetadataLoader.java#L264) which may have already been changed to an unmodifiableList after the initial initialization of `TypeLibrary`. This is of concern for JFR support in GraalVM Native Image. Specifically, multiple initializations of TypeLibrary breaks the ability to use JFR at native image built time. This is because, if JFR is used at image build time, the data of a few of the JFR singletons such as MetadataRepository must be re-initialized for runtime recordings to start with a "clean-slate". However, re-initializing MetadataRepository, also has the effect of calling `TypeLibrary#initialize()` which now unconditionally attempts to initialize TypeRepository, resulting in errors. Example of exception upon second initialization of `TypeRepository`: Caused by: java.lang.InternalError: java.lang.UnsupportedOperationException at jdk.jfr/jdk.jfr.internal.MetadataLoader.createTypes(MetadataLoader.java:195) at jdk.jfr/jdk.jfr.internal.TypeLibrary.initialize(TypeLibrary.java:103) at jdk.jfr/jdk.jfr.internal.MetadataRepository.initializeJVMEventTypes(MetadataRepository.java:72) at jdk.jfr/jdk.jfr.internal.MetadataRepository.<init>(MetadataRepository.java:68) at org.graalvm.nativeimage.builder/com.oracle.svm.core.jfr.Target_jdk_jfr_internal_MetadataRepository.<clinit>(Target_jdk_jfr_internal_MetadataRepository.java:42) at java.base/jdk.internal.misc.Unsafe.ensureClassInitialized0(Native Method) at java.base/jdk.internal.misc.Unsafe.ensureClassInitialized(Unsafe.java:1160) at org.graalvm.nativeimage.builder/com.oracle.svm.hosted.classinitialization.ClassInitializationSupport.ensureClassInitialized(ClassInitializationSupport.java:168) ... 11 more Caused by: java.lang.UnsupportedOperationException at java.base/java.util.Collections$UnmodifiableCollection.add(Collections.java:1085) at jdk.jfr/jdk.jfr.internal.Type.add(Type.java:227) at jdk.jfr/jdk.jfr.internal.MetadataLoader.addFields(MetadataLoader.java:264) at jdk.jfr/jdk.jfr.internal.MetadataLoader.buildTypes(MetadataLoader.java:202) at jdk.jfr/jdk.jfr.internal.MetadataLoader.createTypes(MetadataLoader.java:193) ------------- Commit messages: - Only init TypeLibrary once Changes: https://git.openjdk.org/jdk/pull/13760/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13760&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8307298 Stats: 5 lines in 1 file changed: 4 ins; 0 del; 1 mod Patch: https://git.openjdk.org/jdk/pull/13760.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/13760/head:pull/13760 PR: https://git.openjdk.org/jdk/pull/13760

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RFR: JDK-8300245: Replace NULL with nullptr in share/jfr/
by Johan Sjölen 10 May '23

10 May '23

Do the conversion in the share/jfr/ sub-directory and all of its files. ------------- Commit messages: - More manual fixes - Merge remote-tracking branch 'origin/master' into JDK-8300245 - Manual fixes - Replace NULL with nullptr in share/jfr/ Changes: https://git.openjdk.org/jdk/pull/12034/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12034&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8300245 Stats: 2079 lines in 126 files changed: 0 ins; 0 del; 2079 mod Patch: https://git.openjdk.org/jdk/pull/12034.diff Fetch: git fetch https://git.openjdk.org/jdk pull/12034/head:pull/12034 PR: https://git.openjdk.org/jdk/pull/12034

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RFR: 8307156: native_thread not protected by TLH
by Markus Grönlund 04 May '23

04 May '23

Greetings, this is a small adjustment to correct and extend the scope of the TLH. Testing: jdk_jfr Thanks Markus ------------- Commit messages: - 8307156 Changes: https://git.openjdk.org/jdk/pull/13780/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13780&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8307156 Stats: 6 lines in 1 file changed: 2 ins; 1 del; 3 mod Patch: https://git.openjdk.org/jdk/pull/13780.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/13780/head:pull/13780 PR: https://git.openjdk.org/jdk/pull/13780

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