Files
composable_kernel/include/ck_tile
Anton Gorenko 1e77695fe8 [CK_TILE] Support WMMA (gfx12) in FMHA (#2528)
* Pass hdim to tile_example_fmha_fwd in fp8 tests

* Add WMMA support to fwd FMHA pipelines

* Tune tile sizes a bit for less spilling

fp16 256 is still quite slow

* Fix Q grad tile distribution for warp size = 32 and hdim >= 256

With AccDataType = float and warp size = 32, K0 becomes 0, K repeat is required to correcty distribute the tile.

* Use code based on BlockDropout in BlockDropoutBwd

* Fix split KV combine kernel for gfx12 (warp size 32) and make it more universal

* Fix LSE LDS tensor descriptors: kMaxSplits and kM0 were swapped, it worked on gfx9
  because they both equal to 8 while on gfx12 they are 8 and 4;
* Fix Oacc LDS tensor descriptor: it was transposed even though its shape=[4 * kM0, kN1],
  it worked on gfx9 because 4 * kM == kN1 == 32;
* Removing these hidden dependecies allows to support:
    * any number of warps (power-of-2), not only 4;
    * kN1 = 16, not only 32;
    * any number of splits;

* Rename ids like o_acc_4 and Oacc4 to eliminate confusion: kNumWarps doesn't have to be 4 now

* Replace hard-coded kN1 in dispatch code with the requested tile size

* Add gfx12-specific tile sizes for split KV

* Pass GPU architecture to kernel generation scripts

This is still a temporary solution.

* Build and run FMHA CI tests for gfx12

* Fix issue after merging

* Fix bwd tile sizes

The current pipelines always read only one tile K and V tile, this
requires bk0 == bhdq and bk2 == bhdv (kK0 == kQKHeaddim and
kK2 == kVHeaddim).

* Use hardware f32->f8 on gfx12, remove v_perm

__builtin_amdgcn_perm is not needed because
__builtin_amdgcn_cvt_pk_fp8_f32 allows to specify which word (16 bit of
 32-bit dword) is used to store results (two f8 values).

* Update changelog

* Add WMMA support to pagedkv

* Fix scripts after rebasing

* Support 16x16 (MFMA, WMMA) and 32x32 (MFMA) tiles in fwd and bwd BlockDropout

Add comments with dropout implementation details

Fix performance regression of fwd+dropout

    * Remove some usage of type punning (reinterpret_cast with ref or ptr) in Philox;
    * "scalarize" seed and offset, they may come either from kernel args or from device memory
      (presumably loaded with vector loads).

    These changes help the compiler to procude more optimal code and reduce register spilling.

Use WarpGemmDispatcher instead of explicit WarpGemmMfma... to get  CWarpDstrEncoding

Use code based on BlockDropout in BlockDropoutBwd

Refactor BlockDropout (fwd)

Implement BlockDropout (fwd) for WMMA

    Originally BlockDropout only supported 32x32 tiles (IsWG32 = true),
    this version supports 16x16 tiles.
    If MPerBlock > MWarp * 16, it can generate numbers for two 16x16 tiles, similarly
    to BlockDropoutBwd.

Implement BlockDropoutBwd for WMMA

Remove MakeRandValLds* functions unused in BlockDropoutBwd

Remove unused Run overload from BlockDropoutBwd

* Fix regression with philox seed and offset when they exceed 32-bit int

__builtin_amdgcn_readfirstlane works with 32-bit values, seed and offset
are 64-bit so they get truncated.

* Fix names after cherry-picking

* Fix selection of a fallback tile based on bm0

The assumption that the largest bm0 == 128 is not always true for
current fp32 tiles.

* Do not use filters related to qr_async_trload

They disable tiles/pipelines which are valid for gfx12.

* Use different dstr encoding when C is transposed

* Do not call GetQKBlockGemm (and hence WarpGemmDispatcher) in host code

Some WarpGemmDispatcher instantiations are defined only
for specific archs and undefined on host.
Calculations related to sched barriers are moved from Pipeline's public
fields into pipeline's operator().

* Fix incorrect name WarpGemmMfmaFp8Fp8F32M32N32K16SwizzleBTransposedCDistribution

Correct name is WarpGemmMfmaFp8Fp8F32M32N32K32SwizzleBTransposedCDistribution
because it's 32x32x16 with IterateK = 2 so K = 32, also all tiles used
in codegen scripts are 32, 32, 32.

* Generalize usages of WarpGemmDispatcher for MFMA and WMMA

WarpGemmMfmaFp8Fp8F32M32N32K32SwizzleBTransposedCDistribution is still
used explicitly becaus of swizzle factor = 4.

* Mark has_load_tr as maybe_unused

There are no transpose loading for RDNA.

* Remove CK_TILE_USE_MFMA/WMMA from fmha-related code

* Detect BlockSize on host based on warp size of the current device

If kBlockSize == kNumWarps * get_warp_size(), the kernel is launched with
kBlockSize / 2 because on host get_warp_size() == 64 always.

* Fix calculation of grid size for combine kernel with warp size = 32

* Add missing includes and header

* Support multiple archs in one binary for fwd

* Support multiple archs in one binary for fwd_splitkv, fwd_appendkv, pagedkv_prefill

* Support multiple archs in one binary for bwd

* trload kernels are compiled only for gfx950;
* instances with padding are checked after instances without padding so
  they can be used as fallbacks (similarly to fwd);

* Extract common code from register_traits

* Revert "Fix regression with philox seed and offset when they exceed 32-bit int"

To simplify merging , the proper fix is in develop already.

* Support new numerical d paddings in trait ordering checks

* Build fp32 tests only on gfx9

* Do not use hardcoded M0 = 64 for dot bwd kernel

* Use textwrap.indent from standard library

* Make fp8 pipelines on gfx12 consistent with gfx9

* Update tests for current pipelines

* Make ninja check more responsive in CI

ninja buffers output so this job looks hanging.

* Support fp8fp32 by limiting O vector size

The fp32 output type requires storing 8 * sizeof(float) = 32 bytes,
which is not implemented (here 8 is the number of C values per lane for
v_wmma_f32_16x16x16...).

* Remove unused cmake options

* Unify including  amd_buffer_addressing.hpp/_builtins.hpp

* Temporarily use amd_buffer_addressing.hpp on >=gfx10

amd_buffer_addressing_builtins.hpp uses inline asm for loads/stores
which is not compatible with >=gfx10:
 * 1 scalar for exec masks instead of 2,
 * gfx12 uses different instruction names etc.

* Update asm in bf16 conversions to work with warp 32

* Do not generate splitkv/appendkv with vlayout=col for consistency with fwd

* Add arch tags to kernels/host funcs, compile for each arch separately

* Add kM0 to fmha_bwd_dot_do_o kernel name to match filename

* Add workaround for miscompilation of bwd with padded hdim

SWDEV-559729: v_wmma instructions can be incorrectly placed in divergent
branches used to store padded tensors (when some lanes are inactive due
to padding). Inline asm with dummy dependencies on VGPRs of the tensors
prevents the compiler doing this.

* Fix add_gtest_executable for absolute paths

Some tests (like gemm_tile_engine) pass absolute paths to source files.
In CI the branch name is a part of the root dir, and if the branch name
contains "wmma", "xdl" etc., files can be incorrectly excluded.

* Run only hdim 128 smoke tests for fp8fp32

There are no instances for hdim 64 and 256.

* Format py with ruff to simplify merging develop

* Fix incorrect var name

* Codegen for gfx9,gfx950 when --targets is not specified

Aiter and Pytorch require changes for passing their targets to the codegen scripts.
With this temporary solution the files are generated but not all of them
have to be really built (depending on the used --offload-arch=).

* Combine arch-related values into ArchTrait

This more centralized approach removes duplication of various formatting templates.

* Try a workaround for Jenkins error "groovyjarjarasm.asm.MethodTooLargeException: Method too large"

Some code is extracted into a function.
2025-10-29 13:31:08 -07:00
..
2024-12-12 11:54:03 +08:00

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Composable Kernel Tile

concept

ck_tile provides a programming model with templated abstractions to enable users to implement performance-critical kernels for machine learning workloads. introduces following basic concepts to help users building your own operator

  • tensor coordinate transformation, this is the core concept of layout/index transform abstraction in both compiler time and run time.
  • tile-based programming model, including tile-level api and the concept of distributed tensor.

ck_tile is independently from the old ck, located under /include/ck_tile. You don't need to include anything from old CK, ck_tile has similiar (indeed almost the same) implementations for users to build operators. We will have a transition period to pull everything from old ck into ck_tile, stay tuned.

component

ck_tile is splitted into several componenets including core, host, ops/gemm, ops/fmha... each component you only need to include a single header (e.g #include "ck_tile/core.hpp", #include "ck_tile/ops/fmha.hpp") then you are able to use the function/structure inside (different from old ck)

[core]
ck_tile/core contains all the basic data structure and function to build the kernel, you can only include this header and build your own operators that utilizing all the basic building blocks introduced in ck.

core/container

  • array, store runtime variables with fixed length (tensor index, register buffer, etc...)
  • tuple, same as std::tuple, hold different type of data, and one of the solution to achieve multiple buffer.
  • sequence, compile time integer sequence used to build various internal structures, or to describe tile size
  • other convenient structure build on top of above 3

core/numeric

  • gpu data type like fp16_t, bf16_t, fp8_t... and the conversion between each other
  • constexpr integer similiar to std::integral_constant to be used as compile time integer.
  • math functions and numeric utilities

core/algorithm

  • coordinate transformation system, used to build tensor transform and compile time indexing. This is the core idea introduced in old ck to describe how a tensor is build by several basic transform primitives like merge/unmerge/embed etc... and how we indexing into a ND tensor that finally mapped to 1D memory offset.

core/tensor

  • tensor descriptor, to describe how a ND tensor
  • distributed tensor, describe the storage of this tensor, and the distribution of how a collection of threads collaborately work for this tensor.
  • tile level API, including load_tile, store_tile, shuffle_tile, slice_tile, etc...

[host]
ck_tile/host contains all the host side utilities to launch a kernel, create the device buffer, and some reference implementations. This can be used to create examples (like that under ck_tile example folder) and simple executable to invoke this kernel, so if you only need ck_tile to build your own device library then it's OK to not include this. Based on this, it is recommended to include the specific header you needed under this folder to avoid including unwanted headers (e.g, only include ck_tile/host/kernel_launch.hpp), unless you are writing a host executable.

[ops/gemm, ops/fmha, ops/reduce...]
our implementation of different device operators.

  • warp, warp tile level operator
  • block, block tile level operator
  • pipeline, pipeline that can achieve a customized tile level mainloop (or epilogue). By switching different pipeline to the kernel template you can have different kind of pipeline optimizations.
  • kernel, template interface for users to instantiate a particular kernel

[ops/epilogue]
epilogue part of our kernel. We may extend this epilogue part to let users to build their own cutomized epilogues.

[ref]
reference implementation of cpu or gpu. This folder is supposed to include a specific header on demand.

examples

currently we put all ck_tile related example under /example/ck_tile folder. Please check each example's subfolder.