lightseekorg--tokenspeed/tokenspeed-kernel/python/tokenspeed_kernel/ops/tuning.py

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"""Kernel autotune lifecycle.

Ops that autotune lazily (e.g. the flashinfer trtllm MoE) consult
:func:`autotune_frozen` before starting a new tuning run. The runtime calls
:func:`freeze_autotuning` once engine startup (model load, CUDA-graph capture,
warmup) completes, because an autotune during serving is a hazard twice over:
it blocks the launch thread for the whole profiling run, and under tensor
parallelism ranks that tune at different times miss their next collective and
deadlock. Shapes first seen after the freeze run on each library's fallback
tactics instead -- slower, never stalled.
"""

__all__ = ["autotune_frozen", "freeze_autotuning"]

_frozen = False


def autotune_frozen() -> bool:
    """Whether lazy autotuning is frozen (engine is serving)."""
    return _frozen


def freeze_autotuning() -> None:
    """Disallow any further lazy autotune runs (call once startup completes)."""
    global _frozen
    _frozen = True