sessionctx: fix a deadlock when set tidb_restricted_read_only = true (#55407)

[ti-chi-bot]

This is an automated cherry-pick of #55407

What problem does this PR solve?

Issue Number: close #55373, close #53822,

Problem Summary: follow #40283

What changed and how does it work?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)

run shell below, reach more than 10000

count=0
while true; do
mysql -h 127.0.0.1 -P 4000 -u root -e "set global tidb_restricted_read_only = 1;set global tidb_restricted_read_only = 0;";
count=$((count+1))
echo "$count"
done

• No need to test

  • I checked and no code files have been changed.

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

[ti-chi-bot]

This cherry pick PR is for a release branch and has not yet been approved by triage owners.
Adding the do-not-merge/cherry-pick-not-approved label.

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[ti-chi-bot]

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Details

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[codecov]

Codecov Report

❌ Patch coverage is 40.00000% with 3 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (release-8.1@1fb40c6). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-8.1     #62744   +/-   ##
================================================
  Coverage               ?   71.2321%           
================================================
  Files                  ?       1469           
  Lines                  ?     424515           
  Branches               ?          0           
================================================
  Hits                   ?     302391           
  Misses                 ?     101572           
  Partials               ?      20552           

Flag	Coverage Δ
unit	71.2321% <40.0000%> (?)

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

Components	Coverage Δ
dumpling	52.9656% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	41.5603% <0.0000%> (?)

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