*: avoid unlock of unlocked mutex panic on TableDeltaMap

[tiancaiamao]

What problem does this PR solve?

Issue Number: close #57798

Problem Summary:

What changed and how does it work?

It's most likely that unlock of unlocked mutex is caused by the struct assignment that overwrite the mutex field.

goroutine1:
mu.Lock()
                                                            goroutine2:
                                                            mu = &struct{ }   
defer mu.Unlock()                              <- unlock of unlocked mutex

The old code is weird, tdmLock is used to protect TableDeltaMap but it's not goes together with TableDeltaMap.

I wrap TableDeltaMap into a struct and provide Clone() and Visit() function to it.

Just tiny workaround!

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Some kind of data race, not easy to check in the unit test way

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[tiprow]

Hi @tiancaiamao. Thanks for your PR.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 73.8733%. Comparing base (d021648) to head (821393c).
Report is 30 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #57799        +/-   ##
================================================
+ Coverage   73.1421%   73.8733%   +0.7312%     
================================================
  Files          1671       1674         +3     
  Lines        460703     462857      +2154     
================================================
+ Hits         336968     341928      +4960     
+ Misses       102998     100244      -2754     
+ Partials      20737      20685        -52     

Flag	Coverage Δ
integration	43.4332% <100.0000%> (?)
unit	72.5838% <100.0000%> (+0.3092%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	52.6910% <ø> (ø)
parser	∅ <ø> (∅)
br	45.9953% <ø> (+0.0060%)	⬆️

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-12-04 02:05:59.173291283 +0000 UTC m=+1206946.792945784: ☑️ agreed by lcwangchao.
• 2024-12-04 02:34:29.900881923 +0000 UTC m=+1208657.520536439: ☑️ agreed by ekexium.

[yudongusa]

We need to think about how to build test on the situations like this.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ekexium, lcwangchao, yudongusa

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.5: #57997.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.5: #58122.