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97ca00e449
[CK Tile] Stream-K RDNA Support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit ## Motivation Currently, CK Tile Stream-K only supports CDNA architectures. This change adds Stream-K support on RDNA3/3.5 and RDNA4 architectures. ## Technical Details Stream-K currently has 3 reduction strategies: 1) atomics, 2) linear, and 3) tree. The linear and tree reductions require inter-workgroup communication to a global flags buffer and a global partials buffer. To ensure cache coherency, we use cache modifiers to skip cache levels that are not visible to all workgroups. On CDNA architectures, scalar load and scalar store instructions are available, which we use to read and write to the flags buffer with appropriate cache skipping modifiers. However, RDNA architectures do not support scalar store instructions, so workgroups must use a buffer store instruction to write to flags. Additionally, cache modifiers differ between CDNA and RDNA; they also differ between RDNA3 and RDNA4. Given this information, the main changes are as follows: - Added RDNA flag signaling: Use buffer store instructions for writing to global flags buffer - Add appropriate cache modifiers for reading and writing to flags and partials: - RDNA3 (gfx11): Use `glc | dlc` coherence flags - RDNA4 (gfx12): Use `DEVICE` coherence scope - SFINAE-guarded overloads: Added compile-time dispatch for `SignalStorePartialDone()` and `WaitStorePartialDone()` based on target architecture - RDNA alignment requirements: Increased flags buffer alignment from 128B to 256B due to RDNA cache line size **A note about the `amd_buffer_coherence_enum`:** - **Problem:** The `amd_buffer_coherence_enum` uses preprocessor conditionals (`#if defined(__gfx12__)`) to define architecture-specific values. Template specializations reference enum values from different architectures (e.g., `glc_dlc` for GFX11). Due to C++ two-phase name lookup, non-dependent names are resolved during template parsing regardless of which architecture is being compiled, causing compilation failures when referenced values do not exist in the active preprocessor branch. - **Temporary Solution**: Added compatibility enum values to each architecture block. For example, I added `glc_dlc` in the `__gfx12__` block. I will create a ticket to refactor this enum with a design that has better scalability and tries to avoid the use of preprocessor conditionals. ## Test Plan ### Summary gtests were added to test wmma variants of Stream-K. These tests were stressed tested locally on gfx11 and gfx12. ### More details This PR makes the following changes/additions to the Stream-K gtests: - Split tests into MFMA (CDNA) and WMMA (RDNA) variants - Added 16 WMMA kernel types: FP16/BF16/FP8/BF8 × Linear/Tree reduction - WMMA uses 16×16×16 wave tiles for RDNA (this is the only tile size supported on RDNA) - Fixed RDNA WGP mode: multiply multiProcessorCount by 2 for actual CU count - As described in [HIP documentation](https://rocm.docs.amd.com/projects/HIP/en/docs-7.2.0/doxygen/html/group___global_defs.html#ggacc0acd7b9bda126c6bb3dfd6e2796d7ca3ac50041beb59111a5c76edf03da0898), when in Workgroup Processor (WGP) mode, the value of `hipDeviceAttributeMultiprocessorCount` is half of CUs, because a single WGP contains two CUs. The default mode on RDNA is WGP mode, so when creating (M, N, K) instances for gtests using the CU count, we need to multiply the CU count by 2 to get the correct value. This is not needed in the kernel host code, because the occupancy ensures that overall `max_active_wgs` is correct. ## Test Result All tests pass locally. ## Submission Checklist - [x] Look over the contributing guidelines at https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.
ck_tile/core
ck_tile/core contains every basic functions and structures to create a GPU kernel using ck_tile. User should only include ck_tile/core.hpp this single header to use all the functionality. Everything is under ck_tile namespace. The coding style under this folder should be similar to std (snake_case for structure/function, Camel for template types...)
algorithm/
coordinate transform and some other reusable algorithm
arch/
contains some basic device building block like mma, buffer addressing, etc...
container/
contains basic container data structure, array/sequence/tuple/...
numeric/
data type, and data type related math
tensor/
tensor descriptors and tile level API
utility/
other utility function for both host/device