Set during_sample around the worker's final internal-thread sample

[eregon]

thread_context_collector_profiler_internal_thread_done documents "Assumption 1: When called while the profiler is active, during_sample MUST be set", but release_gvl_and_run_sampling_trigger_loop called it bare.

The profiler is still active at that point: disable_hooks and the active_sampler_instance_state = NULL reset only run after rb_protect returns in _native_sampling_loop. So on_newobj_event and on_gc_event can still fire and would observe during_sample unset while we sample the worker thread's own sampling_buffer.

Route the call through _native_profiler_internal_thread_done, the other caller of the same function, which already wraps it in during_sample_enter + rb_ensure(..., during_sample_exit_ensure).

What does this PR do?

Motivation:

Change log entry

Additional Notes:

How to test the change?

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-08T15:01:29.481397Z	87a6c70	PR opened
🔒 Security Review	✅ Completed 2026-10-08T15:02:31.734296Z	87a6c70	PR opened

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[datadog-official]

✅ All CI checks and tests passed.

🎉 All green!

🧪 All tests passed
❄️ No new flaky tests detected

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 90.65% (+0.00%)

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[pr-commenter]

Benchmarks

Benchmark execution time: 2026-10-08 15:26:17

Comparing candidate commit 87a6c70 in PR branch fix-during_sample-internal-thread-done with baseline commit ac74293 in branch master.

📊 Benchmarking dashboard

Found 0 performance improvements and 0 performance regressions! Performance is the same for 52 metrics, 0 unstable metrics.

Explanation

This is an A/B test comparing a candidate commit's performance against that of a baseline commit. Performance changes are noted in the tables below as:

• 🟩 = significantly better candidate vs. baseline
• 🟥 = significantly worse candidate vs. baseline

We compute a confidence interval (CI) over the relative difference of means between metrics from the candidate and baseline commits, considering the baseline as the reference.

If the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD), the change is considered significant.

Feel free to reach out to #apm-benchmarking-platform on Slack if you have any questions.

More details about the CI and significant changes

You can imagine this CI as a range of values that is likely to contain the true difference of means between the candidate and baseline commits.

CIs of the difference of means are often centered around 0%, because often changes are not that big:

---------------------------------(------|---^--------)-------------------------------->
                              -0.6%    0%  0.3%     +1.2%
                                 |          |        |
         lower bound of the CI --'          |        |
sample mean (center of the CI) -------------'        |
         upper bound of the CI ----------------------'

As described above, a change is considered significant if the CI is entirely outside the configured SIGNIFICANT_IMPACT_THRESHOLD (or the deprecated UNCONFIDENCE_THRESHOLD).

For instance, for an execution time metric, this confidence interval indicates a significantly worse performance:

----------------------------------------|---------|---(---------^---------)---------->
                                       0%        1%  1.3%      2.2%      3.1%
                                                  |   |         |         |
       significant impact threshold --------------'   |         |         |
                      lower bound of CI --------------'         |         |
       sample mean (center of the CI) --------------------------'         |
                      upper bound of CI ----------------------------------'

[ivoanjo]

👍 Ah very elegant! It's one of those "obvious in retrospect, but I didn't see it when I was working on it". Thanks for the fix