[chenBright]

What problem does this PR solve?

Issue Number: resolve #3672

Problem Summary:

What is changed and the side effects?

Changed:

Side effects:

• Performance effects:

• Breaking backward compatibility:

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Check List:

• Please make sure your changes are compilable.
• When providing us with a new feature, it is best to add related tests.
• Please follow Contributor Covenant Code of Conduct.

[Copilot]

🟡 Changes recommended

The new tests can miscount queued pthread wakeups and fail despite correct semaphore behavior.

1 open issue

• Exclude pre-futex pthread waiters from wake-count assertion · New

What changed in this PR

This PR addresses #3672 by making semaphore posts wake waiters according to newly posted permits rather than the previous semaphore count, avoiding unnecessary wakeups under contention.

Changes:

• Pass the posted permit count to butex_wake_n.
• Add regression tests for single-permit, batch, and zero-permit posts across different initial counts.

File	Description
test/​bthread_semaphore_unittest.cpp	Adds wake-count regression tests using bthread and pthread waiters.
src/​bthread/​semaphore.cpp	Corrects the wake limit and removes the unused previous count.

_{Review effort: Balanced}

[Copilot]

🟢 Approval recommended

The focused fix matches the wakeup API contract, and the regression tests cover the affected behavior with no unresolved findings.

No open issues 🎉

1 resolved since last review

• Exclude pre-futex pthread waiters from wake-count assertion

_{Review effort: Balanced}