Support CRaC with Java agents that use appendToBootstrapClassLoaderSearch #162
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…arch Instrumentation.appendToBootstrapClassLoaderSearch(jarfile) creates a file descriptor for the jarfile in native code that cannot be closed or claimed from Java. These FDs can be ignored and left to the CRaC engine.
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❗ This change is not yet ready to be integrated. |
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Hi @mcculls , the fix looks good - do you think you could accompany it with a test case? |
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Hi @rvansa - yes I can add a test case |
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/covered |
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| ClassPathEntry* e = first_append_entry(); | ||
| while (e != nullptr) { | ||
| if (strcmp(e->name(), path) == 0) { | ||
| return true; | ||
| } | ||
| e = e->next(); | ||
| } |
There was a problem hiding this comment.
Just a nitpick:
| ClassPathEntry* e = first_append_entry(); | |
| while (e != nullptr) { | |
| if (strcmp(e->name(), path) == 0) { | |
| return true; | |
| } | |
| e = e->next(); | |
| } | |
| for (ClassPathEntry* e = first_append_entry(); e != nullptr; e = e->next()) { | |
| if (strcmp(e->name(), path) == 0) { | |
| return true; | |
| } | |
| } |
Instrumentation.appendToBootstrapClassLoaderSearch(jarfile)ends up creating a file descriptor for the jarfile in native code that cannot be closed or claimed from Java:https://github.com/openjdk/jdk/blob/jdk-25%2B2/src/hotspot/share/prims/jvmtiEnv.cpp#L671
These FDs can be ignored and left to the CRaC engine.
Without this change you cannot use CRaC with Java agents that call
appendToBootstrapClassLoaderSearch, unless you use-XX:CRAllowedOpenFilePrefixesas a workaround.Progress
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gitCheckout this PR locally:
$ git fetch https://git.openjdk.org/crac.git pull/162/head:pull/162$ git checkout pull/162Update a local copy of the PR:
$ git checkout pull/162$ git pull https://git.openjdk.org/crac.git pull/162/headUsing Skara CLI tools
Checkout this PR locally:
$ git pr checkout 162View PR using the GUI difftool:
$ git pr show -t 162Using diff file
Download this PR as a diff file:
https://git.openjdk.org/crac/pull/162.diff