8258652: Assert in JvmtiThreadState::cur_stack_depth() can noticeably slow down debugging single stepping

[plummercj]

There is an assert in JvmtiThreadState::cur_stack_depth() that tends to slow down single stepping a lot when running the debuggee with a debug jvm. See CR for details. The fix is to allow disabling of this assert using the new EnableJVMTIStackDepthAsserts global, which defaults to true.

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Progress

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Issue

• JDK-8258652: Assert in JvmtiThreadState::cur_stack_depth() can noticeably slow down debugging single stepping

Reviewers

• Serguei Spitsyn (@sspitsyn - Reviewer)
• David Holmes (@dholmes-ora - Reviewer)
• Alex Menkov (@alexmenkov - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/1835/head:pull/1835
$ git checkout pull/1835

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[dholmes-ora]

This works but I'm concerned if this sets a precedent for adding expensive assertions? Do we already have similar flags?

[plummercj]

This works but I'm concerned if this sets a precedent for adding expensive assertions? Do we already have similar flags?

@dholmes-ora The one expensive assert is already there. I have since removed the two additional expensive asserts for the incr() and decr() APIs. I don't know of any other similar flag.

[mlbridge]

Webrevs

• 00: Full (c3e117c)

[plummercj]

Ping! Still need 2 reviews for this one too.

[sspitsyn]

LGTM
Thanks,
Serguei

[openjdk]

@plummercj This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8258652: Assert in JvmtiThreadState::cur_stack_depth() can noticeably slow down debugging single stepping

Reviewed-by: sspitsyn, dholmes, amenkov

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 299 new commits pushed to the master branch:

• a6b2162: 8259278: Optimize Vector API slice and unslice operations
• da6bcf9: 8255019: Shenandoah: Split STW and concurrent mark into separate classes
• aba3431: 8258956: Memory Leak in StringCoding on ThreadLocal resultCached StringCoding.Result
• 8554fe6: 8253866: Security Libs Terminology Refresh
• c2a3c7e: 8259727: Remove redundant "target" arguments to methods in Links
• 1620664: 8259723: Move Table class to formats.html package
• 38a1201: 8258912: Remove JVM options CountJNICalls and CountJVMCalls
• be57cf1: 8226416: MonitorUsedDeflationThreshold can cause repeated async deflation requests
• c822eda: 8259699: Reduce char[] copying in URLEncoder.encode(String, Charset)
• ff3e6e4: 8259773: Incorrect encoding of AVX-512 kmovq instruction
• ... and 289 more: https://git.openjdk.java.net/jdk/compare/6e824b3f51591c48b47fcad71f25c1d9dbc3740a...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[dholmes-ora]

LGTM.

Thanks,
David

[plummercj]

/integrate

[openjdk]

@plummercj Since your change was applied there have been 300 commits pushed to the master branch:

• d18d26e: 8259350: Add some internal debugging APIs to the debug agent
• a6b2162: 8259278: Optimize Vector API slice and unslice operations
• da6bcf9: 8255019: Shenandoah: Split STW and concurrent mark into separate classes
• aba3431: 8258956: Memory Leak in StringCoding on ThreadLocal resultCached StringCoding.Result
• 8554fe6: 8253866: Security Libs Terminology Refresh
• c2a3c7e: 8259727: Remove redundant "target" arguments to methods in Links
• 1620664: 8259723: Move Table class to formats.html package
• 38a1201: 8258912: Remove JVM options CountJNICalls and CountJVMCalls
• be57cf1: 8226416: MonitorUsedDeflationThreshold can cause repeated async deflation requests
• c822eda: 8259699: Reduce char[] copying in URLEncoder.encode(String, Charset)
• ... and 290 more: https://git.openjdk.java.net/jdk/compare/6e824b3f51591c48b47fcad71f25c1d9dbc3740a...master

Your commit was automatically rebased without conflicts.

Pushed as commit 4f881ba.

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