executor: fix HashJoinExec panic of closed channel

[Qiaolin-Yu]

What problem does this PR solve?

Issue Number: close #37932

Problem Summary:

What is changed and how it works?

Apply will Open and Close an operator multiple times. The HashJoin below Apply returns an error in line 171 during Open, thus e.closeCh is not re-initialized, and the e.closeCh be closed in HashJoin.Close is an already closed channel in the last round.
To solve it, we set e.closeCh to nil in the Close function.

Check List

Tests

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

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]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• LittleFall
• XuHuaiyu

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[Qiaolin-Yu]

/cc @bestwoody

[Qiaolin-Yu]

/cc @XuHuaiyu

[ti-chi-bot]

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[bestwoody]

is it safe to just set closeCh to nullptr. please ensure the user will check null of closeCh, and not do a null access.

[Qiaolin-Yu]

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #38666.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #38667.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #38668.

[sre-bot]

TiDB MergeCI notify

🔴 Bad News! New failing [3] after this pr merged.
These new failed integration tests seem to be caused by the current PR, please try to fix these new failed integration tests, thanks!

CI Name	Result	Duration	Compare with Parent commit
idc-jenkins-ci-tidb/integration-common-test	🟥 failed 1, success 16, total 17	11 min	New failing
idc-jenkins-ci-tidb/sqllogic-test-2	🟥 failed 2, success 26, total 28	6 min 2 sec	New failing
idc-jenkins-ci-tidb/sqllogic-test-1	🟥 failed 4, success 22, total 26	4 min 14 sec	New failing
idc-jenkins-ci-tidb/integration-ddl-test	🔴 failed 1, success 5, total 6	24 min	Existing failure
idc-jenkins-ci-tidb/common-test	🔴 failed 2, success 9, total 11	11 min	Existing failure
idc-jenkins-ci/integration-cdc-test	🟢 all 38 tests passed	21 min	Existing passed
idc-jenkins-ci-tidb/tics-test	🟢 all 1 tests passed	6 min 32 sec	Existing passed
idc-jenkins-ci-tidb/mybatis-test	🟢 all 1 tests passed	3 min 3 sec	Existing passed
idc-jenkins-ci-tidb/integration-compatibility-test	🟢 all 1 tests passed	2 min 53 sec	Existing passed
idc-jenkins-ci-tidb/plugin-test	🟢 build success, plugin test success	4min	Existing passed

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #38712.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #38713.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #38714.

[ti-chi-bot]

In response to a cherrypick label: new pull request created: #38715.