loopyt 39b086d781 feat(h20): route tile_kernels calls through a compat layer, so the model runs without TileLang
The references were importable and numerically validated, but nothing pointed the model at them:
the forward pass still called the compiled kernels, which raise ModuleNotFoundError on a host
without TileLang. This adds the routing layer and swaps the call sites.

`deepinfer/tk_compat/` exposes the *compiled* signatures -- out-buffers, in-place conventions,
argument order -- because that is what the 25 call sites are written against, and adapts to the
reference's shape internally. Selection is `DEEPINFER_KERNELS=auto|cuda|ref`; `auto` follows
whether TileLang imports.

The adapters are not pass-throughs. Each difference was found by running both backends:

* `per_token_cast` takes `num_per_channels=n`, the reference takes `block_size=(1, n)`.
* `apply_rotary` takes a concatenated cos|sin cache and rotates in place returning None; the
  reference takes cos and sin separately and returns a new tensor. The adapter splits, calls, and
  copies back, because the call site relies on the in-place contract.
* `engram_gate` takes the pre-multiplied weight and `(eps, clamp_value)`; the reference needs the
  two weights separately and `(clamp_value, eps)`. Since a product cannot be un-multiplied,
  `fused_weight` returns the pair on the reference path and the gate unpacks it.
* `mhc_pre_big_fuse_fwd` has no single reference: its five steps are composed from the reference's
  own components.
* `mhc_reduce_partials_and_rmsnorm_fwd` likewise; rebuilt from the reference's formula.

`moe_topk_gate(force_random=...)` raises rather than silently ignoring the flag. The reference has
no equivalent, and dropping it would route tokens differently while looking healthy.

Verification, all on the real call signatures: 18 cases compared between `cuda` and `ref` modes,
`ALL_MATCH`, 12 bitwise identical including every quantised byte and every routing index; plus a
smoke run that executes all 23 APIs with TileLang blocked, `ALL_CALLS_OK`.

End to end still has not completed, and the reason is not this change: six GPUs on the host are
held by other containers (82 GiB of 139 each), so the 8-way EP run OOMs in allocate_userbuffer and
the surviving ranks wait at a barrier. Recorded in the doc along with the command to rerun it.
2026-10-22 18:10:14 +08:00

95 lines
3.5 KiB
Python

"""Route `tile_kernels` calls to either the compiled kernels or the pure-torch references.
Why this exists: the model forward calls `tile_kernels` directly in 13 modules (quantisation,
SwiGLU, MoE routing, RoPE, MHC, Engram). Those kernels are TileLang programs, so on an
accelerator where TileLang cannot be built, nothing runs. `tile_kernels.torch` carries a
reference implementation of nearly all of them, and this package makes the choice a one-line
change at each call site:
import tile_kernels -> from deepinfer import tk_compat as tile_kernels
Call sites keep writing `tile_kernels.quant.per_token_cast(...)`, so no other line changes. The
signatures exposed here are the *compiled* ones -- including the `out=` buffers and the in-place
conventions -- because that is what the call sites are written against; each module adapts to the
reference's shape (different keyword names, return values instead of out parameters) internally.
Selection is by `DEEPINFER_KERNELS`, defaulting to `auto`:
* ``auto`` -- compiled if TileLang is importable, references otherwise
* ``cuda`` -- always compiled; fails loudly if TileLang is absent
* ``ref`` -- always references, even where TileLang exists (for A/B testing)
Every operator implemented here has been checked numerically against the compiled version; the
one known gap is `moe_topk_gate`'s `force_random`, which the reference does not accept -- see
`deepinfer.tk_compat.moe`.
"""
import importlib
import os
_SUBMODULES = frozenset({"config", "engram", "mhc", "moe", "quant", "torch", "transform", "utils"})
# `tile_kernels` re-exports the launch knobs at the top level, and `worker/runtime_config.py`
# calls `tile_kernels.set_pdl(...)`. Keeping that surface is what lets the call sites read the
# same after the import swap, so these resolve through `config` on first access.
_CONFIG_EXPORTS = frozenset(
{
"get_amax_clamp_for_quant",
"get_deterministic_algorithms",
"get_device_num_sms",
"get_num_ai_cores",
"get_num_cube_cores",
"get_num_sms",
"get_num_vec_cores",
"get_pdl",
"get_token_alignment",
"is_ascend",
"set_amax_clamp_for_quant",
"set_num_sms",
"set_pdl",
"set_token_alignment",
"use_deterministic_algorithms",
}
)
def use_references() -> bool:
"""Whether calls should resolve to the pure-torch references."""
mode = os.getenv("DEEPINFER_KERNELS", "auto").strip().lower()
if mode == "ref":
return True
if mode == "cuda":
return False
if mode != "auto":
raise ValueError(f"DEEPINFER_KERNELS must be auto, cuda or ref, got {mode!r}")
return not compiled_available()
def compiled_available() -> bool:
"""Whether the compiled kernels can actually run here.
TileLang is the gate, not `tile_kernels`: the package's own Python is importable anywhere,
which is what makes the reference path reachable in the first place.
"""
try:
import tilelang # noqa: F401
except ImportError:
return False
return True
def __getattr__(name: str):
if name in _SUBMODULES:
module = importlib.import_module(f".{name}", __name__)
globals()[name] = module
return module
if name in _CONFIG_EXPORTS:
value = getattr(importlib.import_module(".config", __name__), name)
globals()[name] = value
return value
raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
def __dir__() -> list[str]:
return sorted(set(globals()) | _SUBMODULES | _CONFIG_EXPORTS)