Fix profiler collector wakeup on quiesce

[doraemonmj]

Summary

• Wake ready-queue consumers after publishing quiesce or stop control state.
• Make the control predicate level-triggered and synchronize notifications with each shard's wait mutex, closing the notify-before-wait race.
• Keep the 100 ms tick as a fallback while documenting and testing the immediate lifecycle-control path.

ProfilerBase::quiesce() previously published collect_quiesce_epoch_ and waited for acknowledgements without waking collectors blocked in wait_pop_ready(). An idle collector therefore acknowledged only after the 100 ms timeout. Enabled collectors are quiesced serially, so the delay could accumulate.

Performance

A2/A3 onboard, tensormap_and_ringbuffer/paged_attention_unroll::Case1, Chip swimlane level 4, three measured single-run processes after one warmup per arm:

Median	Before	After
chip.run.runner_run	108.92 ms	9.49 ms
Device wall	1.60 ms	1.64 ms
Complete chip.run	225.62 ms	127.73 ms

Each artifact contained 1,024 AICore tasks and 1,280 orchestrator phases. Record counts matched across all runs.

Testing

• ctest --test-dir tests/ut/cpp/build -R 'test_(profiler_base|buffer_pool_manager)$' --output-on-failure
• Control wakeup test repeated 1,000 times
• Combined quiesce/stop/drain tests repeated 100 times
• pre-commit hooks, including clang-tidy, cpplint, clang-format, and markdownlint
• A2/A3 onboard paged-attention A/B through an allocated task-submit device

Fixes #2150

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📝 Walkthrough

Walkthrough

The change adds control-aware wake predicates and synchronized notifications to BufferPoolManager. ProfilerBase uses them for immediate quiesce and stop handling. Unit tests verify prompt wakeups for silent collectors, and documentation describes the updated wait behavior.

Changes

Profiler control wakeup

Layer / File(s)	Summary
Ready-queue wakeup API src/common/platform/include/host/buffer_pool_manager.h, tests/ut/cpp/common/test_buffer_pool_manager.cpp	wait_pop_ready accepts a wake predicate, while notify_ready_waiters() wakes live shard waiters. The unit test verifies a control wake returns without a buffer.
Profiler lifecycle integration src/common/platform/include/host/profiler_base.h, docs/dfx/profiling-framework.md	Quiesce and stop publish lifecycle state, notify ready waiters, and pass lifecycle predicates to the collector loop. Documentation describes the 100 ms wait as a fallback.
Lifecycle wake validation tests/ut/cpp/common/test_profiler_base.cpp	Tests verify that silent collectors complete stop() and quiesce() within 50 ms.

Priority: ➖ Normal — Impact reflects medium issue severity.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Severity of issue fixed: Medium

Merge Risk: 🔵 Low · up to c07a0

Profiler collectors now wake promptly for quiesce and stop requests, but a failure path in the new ready-queue wakeup test can abort the test process rather than cleanly reporting the timeout. This is a bounded test robustness issue that should be corrected before relying on the test result.

Sequence Diagram(s)

sequenceDiagram
  participant ProfilerBase
  participant BufferPoolManager
  participant CollectorLoop
  ProfilerBase->>ProfilerBase: publish quiesce epoch or set execution_complete_
  ProfilerBase->>BufferPoolManager: notify_ready_waiters()
  BufferPoolManager->>CollectorLoop: wake wait_pop_ready()
  CollectorLoop->>ProfilerBase: acknowledge quiesce or exit after drain

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🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 33.33% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 12 functions across 4 files. (1 skipped: …	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the primary change: waking profiler collectors during quiesce.
Description check	✅ Passed	The description directly explains the wakeup fix, synchronization approach, fallback behavior, performance impact, and testing.
Linked Issues check	✅ Passed	The implementation satisfies issue #2150 by adding level-triggered quiesce and stop predicates, synchronized shard notifications, the 100 ms fallback, and lifecycle tests while preserving the final dr…
Out of Scope Changes check	✅ Passed	The code, documentation, and tests remain focused on profiler collector wakeup behavior and the requirements in issue #2150. No unrelated changes are identified.

Full details: Docstring Coverage

Explanation

Docstring coverage is 33.33% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 12 functions across 4 files. (1 skipped: 1 unsupported.)

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Actionable comments posted: 1

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Inline comments:
In `@tests/ut/cpp/common/test_buffer_pool_manager.cpp`:
- Line 347: Replace the fatal ASSERT_EQ on started.wait_for(500ms) with
EXPECT_EQ so a timeout does not bypass cleanup; ensure the test continues to
request wakeup and calls consumer.join().

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ℹ️ Review info

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Configuration used: Organization UI

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📥 Commits

Reviewing files that changed from the base of the PR and between 3ef918d and c07a0d9.

📒 Files selected for processing (5)

• docs/dfx/profiling-framework.md
• src/common/platform/include/host/buffer_pool_manager.h
• src/common/platform/include/host/profiler_base.h
• tests/ut/cpp/common/test_buffer_pool_manager.cpp
• tests/ut/cpp/common/test_profiler_base.cpp

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