HIP: add fattn-mma-f16 for RDNA4 (#18481)

* finish VQ mma

* flash_attn_ext_f16_iter

* KQ_rowsum

* correct exp

* fix scale error

* fix softmax scale

* fix softmax scale

* enable fattn on cpu side

* fix random error

* disable fattn-mma-f16 on rdna3

* fix wrong col for rdna

* use identity mat to transpose

* resolve conflicts

* basic tuning for DeepSeek-R1-Distill-Qwen-1.5B

* fix volta compile error

* align rdna4 policy for fattn

* adjust fattn policy

* adjust kernel selection logic

* update as the review comments

* keep fattn-wmma logic

* adjust kernel selection logic

---------

Co-authored-by: zhang hui <you@example.com>
Co-authored-by: Johannes Gäßler <johannesg@5d6.de>
This commit is contained in:
yulo 2026-01-13 20:52:16 +08:00 committed by GitHub
parent c1e79e610f
commit ea4a321f2a
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6 changed files with 266 additions and 36 deletions

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@ -262,6 +262,10 @@ static const char * cu_get_error_str(CUresult err) {
#define FLASH_ATTN_AVAILABLE
#endif // !defined(GGML_CUDA_NO_FA) && !(defined(GGML_USE_MUSA) && __MUSA_ARCH__ < 220)
#if defined(TURING_MMA_AVAILABLE)
#define LDMATRIX_TRANS_AVAILABLE
#endif // defined(TURING_MMA_AVAILABLE)
static bool fp16_available(const int cc) {
return ggml_cuda_highest_compiled_arch(cc) >= GGML_CUDA_CC_PASCAL ||
(GGML_CUDA_CC_IS_MTHREADS(cc) && cc >= GGML_CUDA_CC_PH1);

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@ -914,7 +914,7 @@ void launch_fattn(
const int nblocks_stream_k = max_blocks;
const bool use_stream_k = cc >= GGML_CUDA_CC_ADA_LOVELACE || tiles_efficiency_percent < 75;
const bool use_stream_k = cc >= GGML_CUDA_CC_ADA_LOVELACE || amd_wmma_available(cc) || tiles_efficiency_percent < 75;
blocks_num.x = use_stream_k ? nblocks_stream_k : ntiles_total;
blocks_num.y = 1;

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@ -98,6 +98,19 @@ static constexpr __host__ __device__ fattn_mma_config ggml_cuda_fattn_mma_get_co
return ggml_cuda_fattn_mma_get_config_ampere(DKQ, DV, ncols);
}
static constexpr __host__ __device__ fattn_mma_config ggml_cuda_fattn_mma_get_config_rdna(const int DKQ, const int DV, const int ncols) {
GGML_CUDA_FATTN_MMA_CONFIG_CASE(256, 256, 16, 128, 2, 64, 128, 128, 128, 2, true);
GGML_CUDA_FATTN_MMA_CONFIG_CASE(256, 256, 32, 128, 2, 64, 128, 128, 64, 2, true);
GGML_CUDA_FATTN_MMA_CONFIG_CASE(256, 256, 64, 128, 2, 64, 128, 128, 64, 2, true);
GGML_CUDA_FATTN_MMA_CONFIG_CASE(576, 512, 16, 64, 4, 32, 96, 64, 128, 1, false);
GGML_CUDA_FATTN_MMA_CONFIG_CASE(576, 512, 32, 128, 2, 32, 160, 128, 128, 1, false);
GGML_CUDA_FATTN_MMA_CONFIG_CASE(576, 512, 64, 256, 1, 32, 160, 128, 128, 1, false);
// TODO tune specifically for RDNA
return ggml_cuda_fattn_mma_get_config_ampere(DKQ, DV, ncols);
}
static __host__ fattn_mma_config ggml_cuda_fattn_mma_get_config(const int DKQ, const int DV, const int ncols, const int cc) {
if (ampere_mma_available(cc)) {
return ggml_cuda_fattn_mma_get_config_ampere(DKQ, DV, ncols);
@ -105,6 +118,9 @@ static __host__ fattn_mma_config ggml_cuda_fattn_mma_get_config(const int DKQ, c
if (turing_mma_available(cc)) {
return ggml_cuda_fattn_mma_get_config_turing(DKQ, DV, ncols);
}
if (amd_wmma_available(cc)) {
return ggml_cuda_fattn_mma_get_config_rdna(DKQ, DV, ncols);
}
GGML_ASSERT(volta_mma_available(cc));
return ggml_cuda_fattn_mma_get_config_volta(DKQ, DV, ncols);
}
@ -116,6 +132,8 @@ static constexpr __device__ fattn_mma_config ggml_cuda_fattn_mma_get_config(cons
return ggml_cuda_fattn_mma_get_config_turing(DKQ, DV, ncols);
#elif defined(VOLTA_MMA_AVAILABLE)
return ggml_cuda_fattn_mma_get_config_volta(DKQ, DV, ncols);
#elif defined(AMD_WMMA_AVAILABLE)
return ggml_cuda_fattn_mma_get_config_rdna(DKQ, DV, ncols);
#else
GGML_UNUSED_VARS(DKQ, DV, ncols);
return fattn_mma_config(32, 1, 0, 0, 0, 0, 0, false);
@ -186,6 +204,23 @@ static constexpr __device__ bool ggml_cuda_fattn_mma_get_Q_in_reg(const int DKQ,
return ggml_cuda_fattn_mma_get_config(DKQ, DV, ncols).Q_in_reg;
}
static constexpr __device__ int get_cols_per_thread() {
#if defined(AMD_WMMA_AVAILABLE)
return 1; // RDNA has a single column.
#else
return 2; // This is specifically KQ columns, Volta only has a single VKQ column.
#endif // defined(AMD_WMMA_AVAILABLE)
}
static __host__ int get_cols_per_warp(const int cc) {
if (turing_mma_available(cc) || amd_wmma_available(cc)) {
return 16;
} else {
// Volta
return 32;
}
}
// ------------------------------------------------------------------------------------------------------------------
static __host__ int ggml_cuda_fattn_mma_get_nstages(const int DKQ, const int DV, const int ncols1, const int ncols2, const int cc) {
@ -393,10 +428,10 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
const int jt,
const int kb0,
const int k_VKQ_sup) {
#if defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE)
#if defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE) || (defined(AMD_WMMA_AVAILABLE) && defined(RDNA4))
constexpr int ncols = ncols1 * ncols2;
constexpr int cols_per_warp = T_B_KQ::I;
constexpr int cols_per_thread = 2; // This is specifically KQ columns, Volta only has a single VKQ column.
constexpr int cols_per_thread = get_cols_per_thread();
constexpr int np = nwarps * (cols_per_warp/ncols2) / ncols1; // Number of parallel CUDA warps per Q column.
constexpr int nbatch_fa = ggml_cuda_fattn_mma_get_nbatch_fa(DKQ, DV, ncols);
constexpr int nbatch_K2 = ggml_cuda_fattn_mma_get_nbatch_K2(DKQ, DV, ncols);
@ -413,6 +448,8 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
const int k_VKQ_0 = kb0 * nbatch_fa;
#if defined(TURING_MMA_AVAILABLE)
T_C_KQ KQ_C[nbatch_fa/(np*(cols_per_warp == 8 ? T_C_KQ::I : T_C_KQ::J))];
#elif defined(AMD_WMMA_AVAILABLE)
T_C_KQ KQ_C[nbatch_fa/(np*T_C_KQ::J)];
#else // Volta
T_C_KQ KQ_C[nbatch_fa/(np*T_C_KQ::J)];
#endif // defined(TURING_MMA_AVAILABLE)
@ -461,8 +498,14 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
if constexpr (cols_per_warp == 8) {
mma(KQ_C[i_KQ_00/(np*T_A_KQ::I)], K_A, Q_B[k_KQ_0/T_A_KQ::J]);
} else {
// Wide version of KQ_C is column-major => swap A and B.
// Wide version of KQ_C is column-major
#if defined(AMD_WMMA_AVAILABLE)
// RDNA matrix C is column-major.
mma(KQ_C[i_KQ_00/(np*T_A_KQ::I)], K_A, Q_B[k_KQ_0/T_A_KQ::J]);
#else
// swap A and B for CUDA.
mma(KQ_C[i_KQ_00/(np*T_A_KQ::I)], Q_B[k_KQ_0/T_A_KQ::J], K_A);
#endif // defined(AMD_WMMA_AVAILABLE)
}
}
}
@ -479,8 +522,14 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
T_A_KQ K_A;
load_ldmatrix(K_A, tile_K + i_KQ_0*stride_tile_K + (k_KQ_0 - k0_start), stride_tile_K);
// Wide version of KQ_C is column-major => swap A and B.
// Wide version of KQ_C is column-major
#if defined(AMD_WMMA_AVAILABLE)
// RDNA matrix C is column-major.
mma(KQ_C[i_KQ_00/(np*T_A_KQ::I)], K_A, Q_B[0]);
#else
// swap A and B for CUDA.
mma(KQ_C[i_KQ_00/(np*T_A_KQ::I)], Q_B[0], K_A);
#endif // defined(AMD_WMMA_AVAILABLE)
}
}
}
@ -532,7 +581,13 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
#pragma unroll
for (int l = 0; l < T_C_KQ::ne; ++l) {
if (!oob_check || k0 + (threadIdx.y % np)*T_C_KQ::I + T_C_KQ::get_i(l) < k_VKQ_sup) {
KQ_max_new[l % 2] = fmaxf(KQ_max_new[l % 2], KQ_C[k0/(np*T_C_KQ::I)].x[l] + FATTN_KQ_MAX_OFFSET);
#if defined(AMD_WMMA_AVAILABLE)
constexpr int KQ_idx = 0;
#else
// Turing + Volta:
const int KQ_idx = l % 2;
#endif // defined(AMD_WMMA_AVAILABLE)
KQ_max_new[KQ_idx] = fmaxf(KQ_max_new[KQ_idx], KQ_C[k0/(np*T_C_KQ::I)].x[l] + FATTN_KQ_MAX_OFFSET);
}
}
}
@ -552,8 +607,14 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
#pragma unroll
for (int l = 0; l < T_C_KQ::ne; ++l) {
if (!oob_check || k0 + (threadIdx.y % np)*T_C_KQ::I + T_C_KQ::get_i(l) < k_VKQ_sup) {
KQ_C[k0/(np*T_C_KQ::I)].x[l] = expf(KQ_C[k0/(np*T_C_KQ::I)].x[l] - KQ_max_new[l % 2]);
KQ_rowsum_add[l % 2] += KQ_C[k0/(np*T_C_KQ::I)].x[l];
#if defined(AMD_WMMA_AVAILABLE)
constexpr int KQ_idx = 0;
#else
// Turing + Volta:
const int KQ_idx = l % 2;
#endif // defined(AMD_WMMA_AVAILABLE)
KQ_C[k0/(np*T_C_KQ::I)].x[l] = expf(KQ_C[k0/(np*T_C_KQ::I)].x[l] - KQ_max_new[KQ_idx]);
KQ_rowsum_add[KQ_idx] += KQ_C[k0/(np*T_C_KQ::I)].x[l];
} else {
KQ_C[k0/(np*T_C_KQ::I)].x[l] = 0.0f;
}
@ -584,8 +645,13 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
#pragma unroll
for (int l = 0; l < T_C_KQ::ne; ++l) {
if (!oob_check || k0 + (threadIdx.y % np)*T_C_KQ::J + T_C_KQ::get_j(l) < k_VKQ_sup) {
#if defined(AMD_WMMA_AVAILABLE)
constexpr int KQ_idx = 0;
#else
// Turing + Volta:
KQ_max_new[(l/2) % 2] = fmaxf(KQ_max_new[(l/2) % 2], KQ_C[(k0/(np*T_C_KQ::J))].x[l] + FATTN_KQ_MAX_OFFSET);
const int KQ_idx = (l/2) % 2;
#endif // defined(AMD_WMMA_AVAILABLE)
KQ_max_new[KQ_idx] = fmaxf(KQ_max_new[KQ_idx], KQ_C[(k0/(np*T_C_KQ::J))].x[l] + FATTN_KQ_MAX_OFFSET);
}
}
}
@ -596,7 +662,11 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
// Values per KQ column are spread across 4 threads:
constexpr int offset_first = 2;
constexpr int offset_last = 1;
#else
#elif defined(AMD_WMMA_AVAILABLE)
// Values per KQ column are spread across 2 threads:
constexpr int offset_first = 16;
constexpr int offset_last = 16;
#else // Volta
// Values per KQ column are spread across 2 threads:
constexpr int offset_first = 2;
constexpr int offset_last = 2;
@ -612,10 +682,15 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
for (int k0 = 0; k0 < nbatch_fa; k0 += np*T_C_KQ::J) {
#pragma unroll
for (int l = 0; l < T_C_KQ::ne; ++l) {
// Turing + Volta:
if (!oob_check || k0 + (threadIdx.y % np)*T_C_KQ::J + T_C_KQ::get_j(l) < k_VKQ_sup) {
KQ_C[(k0/(np*T_C_KQ::J))].x[l] = expf(KQ_C[(k0/(np*T_C_KQ::J))].x[l] - KQ_max_new[(l/2) % 2]);
KQ_rowsum_add[(l/2) % 2] += KQ_C[(k0/(np*T_C_KQ::J))].x[l];
#if defined(AMD_WMMA_AVAILABLE)
constexpr int KQ_idx = 0;
#else
// Turing + Volta:
const int KQ_idx = (l/2) % 2;
#endif // defined(AMD_WMMA_AVAILABLE)
KQ_C[(k0/(np*T_C_KQ::J))].x[l] = expf(KQ_C[(k0/(np*T_C_KQ::J))].x[l] - KQ_max_new[KQ_idx]);
KQ_rowsum_add[KQ_idx] += KQ_C[(k0/(np*T_C_KQ::J))].x[l];
} else {
KQ_C[(k0/(np*T_C_KQ::J))].x[l] = 0.0f;
}
@ -639,7 +714,7 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
#if defined(TURING_MMA_AVAILABLE)
if constexpr (cols_per_warp == 8) {
const half2 KQ_max_scale_h2 = make_half2(KQ_max_scale[0], KQ_max_scale[1]);
const half2 KQ_max_scale_h2 = make_half2(KQ_max_scale[0], KQ_max_scale[cols_per_thread - 1]);
#pragma unroll
for (int i = 0; i < DV/T_C_VKQ::I; ++i) {
#pragma unroll
@ -660,6 +735,16 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
}
}
}
#elif defined(AMD_WMMA_AVAILABLE)
const half2 KQ_max_scale_h2 = make_half2(
KQ_max_scale[0], KQ_max_scale[0]);
#pragma unroll
for (int i = 0; i < (DV/2)/T_C_VKQ::J; ++i) {
#pragma unroll
for (int l = 0; l < T_C_VKQ::ne; ++l) {
VKQ_C[i].x[l] *= KQ_max_scale_h2;
}
}
#else // Volta
const half2 KQ_max_scale_h2 = make_half2(
KQ_max_scale[(threadIdx.x / 2) % 2], KQ_max_scale[(threadIdx.x / 2) % 2]);
@ -707,6 +792,10 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
// Therefore, iterate over V in reverse and re-use the data if possible.
static_assert(!mla || nstages <= 1, "combination of MLA and multi-stage loading not implemented");
constexpr int reusable_cutoff = mla ? (DKQ - 1) - (DKQ - 1) % (2*nbatch_K2) - (DKQ - DV) : DV;
#if defined(AMD_WMMA_AVAILABLE) && !defined(LDMATRIX_TRANS_AVAILABLE)
T_A_VKQ A_identity;
make_identity_mat(A_identity);
#endif // defined(AMD_WMMA_AVAILABLE) && !defined(LDMATRIX_TRANS_AVAILABLE)
// Calculate VKQ tile, need to use logical rather than physical elements for i0 due to transposition of V:
#pragma unroll
@ -727,7 +816,7 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
}
const half2 * tile_V_i = i0_start < reusable_cutoff ? tile_V : tile_V + (i0_start - reusable_cutoff)/2;
#if defined(TURING_MMA_AVAILABLE)
#if defined(TURING_MMA_AVAILABLE) || defined(AMD_WMMA_AVAILABLE)
constexpr int i0_stride = cols_per_warp == 8 ? T_C_VKQ::I : 2*T_C_VKQ::J;
#pragma unroll
for (int i_VKQ_0 = i0_start; i_VKQ_0 < i0_stop; i_VKQ_0 += i0_stride) {
@ -737,12 +826,26 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
const int k0 = k00 + (threadIdx.y % np)*T_A_VKQ::J;
T_A_VKQ A; // Transposed in SRAM but not in registers, gets transposed on load.
#if defined(LDMATRIX_TRANS_AVAILABLE)
load_ldmatrix_trans(A, tile_V_i + 2*k0*stride_tile_V + (i_VKQ_0 - i0_start)/2, stride_tile_V);
#else
// TODO: Try to transpose tile_V when loading gmem to smem.
// Use mma to transpose T_A_VKQ for RDNA.
T_A_VKQ A_trans;
load_ldmatrix(A_trans, tile_V_i + 2*k0*stride_tile_V + (i_VKQ_0 - i0_start)/2, stride_tile_V);
mma(A, A_trans, A_identity);
#endif // defined(TURING_MMA_AVAILABLE)
if constexpr (T_B_KQ::I == 8) {
mma(VKQ_C[i_VKQ_0/i0_stride], A, B[k00/(np*T_A_VKQ::J)]);
} else {
// Wide version of VKQ_C is column-major => swap A and B.
// Wide version of VKQ_C is column-major.
#if defined(AMD_WMMA_AVAILABLE)
// RDNA matrix C is column-major.
mma(VKQ_C[i_VKQ_0/i0_stride], A, B[k00/(np*T_A_VKQ::J)]);
#else
// swap A and B for CUDA.
mma(VKQ_C[i_VKQ_0/i0_stride], B[k00/(np*T_A_VKQ::J)], A);
#endif // defined(AMD_WMMA_AVAILABLE)
}
}
}
@ -761,7 +864,7 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
mma(VKQ_C[i_VKQ_0/i0_stride], B[k00/(np*T_A_VKQ::I)], A);
}
}
#endif // defined(TURING_MMA_AVAILABLE)
#endif // defined(TURING_MMA_AVAILABLE) || defined(AMD_WMMA_AVAILABLE)
if constexpr (nstages <= 1) {
__syncthreads(); // Only needed if tile_K == tile_V.
@ -774,7 +877,7 @@ static __device__ __forceinline__ void flash_attn_ext_f16_iter(
tile_Q, tile_K, tile_V, tile_mask,
Q_B, VKQ_C, KQ_max, KQ_rowsum, kb0);
NO_DEVICE_CODE;
#endif // defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE)
#endif // defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE) || (defined(AMD_WMMA_AVAILABLE) && defined(RDNA4))
}
#if defined(TURING_MMA_AVAILABLE)
@ -794,6 +897,15 @@ template<> struct mma_tile_sizes<8> {
using T_B_VKQ = tile< 8, 8, half2>; // column-major
using T_C_VKQ = tile<16, 4, half2>; // row-major
};
#elif defined(AMD_WMMA_AVAILABLE)
template<int ncols> struct mma_tile_sizes {
using T_A_KQ = tile<16, 8, half2>; // row-major
using T_B_KQ = tile<16, 8, half2>; // column-major
using T_C_KQ = tile<16, 16, float>; // column-major
using T_A_VKQ = tile<16, 8, half2>; // row-major
using T_B_VKQ = tile<16, 8, half2>; // column-major
using T_C_VKQ = tile<16, 8, half2>; // column-major
};
#else // Volta
template<int ncols> struct mma_tile_sizes {
using T_A_KQ = tile< 8, 4, half2, DATA_LAYOUT_I_MAJOR_MIRRORED>; // row-major
@ -828,7 +940,7 @@ static __device__ __forceinline__ void flash_attn_ext_f16_process_tile(
const int jt,
const int kb0_start,
const int kb0_stop) {
#if defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE)
#if defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE) || (defined(AMD_WMMA_AVAILABLE) && defined(RDNA4))
//In this kernel Q, K, V are matrices while i, j, k are matrix indices.
constexpr int ncols = ncols1 * ncols2;
@ -840,7 +952,7 @@ static __device__ __forceinline__ void flash_attn_ext_f16_process_tile(
using T_C_VKQ = typename mma_tile_sizes<ncols>::T_C_VKQ;
constexpr int cols_per_warp = T_B_KQ::I;
constexpr int cols_per_thread = 2; // This is specifically KQ columns, Volta only has a single VKQ column.
constexpr int cols_per_thread = get_cols_per_thread();
constexpr int np = nwarps * (cols_per_warp/ncols2) / ncols1; // Number of parallel CUDA warps per Q column.
constexpr int nbatch_fa = ggml_cuda_fattn_mma_get_nbatch_fa (DKQ, DV, ncols);
constexpr int nbatch_K2 = ggml_cuda_fattn_mma_get_nbatch_K2 (DKQ, DV, ncols);
@ -871,6 +983,8 @@ static __device__ __forceinline__ void flash_attn_ext_f16_process_tile(
T_B_KQ Q_B[(Q_in_reg ? DKQ/(2*T_B_KQ::J) : 1)];
#if defined(TURING_MMA_AVAILABLE)
T_C_VKQ VKQ_C[cols_per_warp == 8 ? DV/T_C_VKQ::I : DV/(2*T_C_VKQ::J)];
#elif defined(AMD_WMMA_AVAILABLE)
T_C_VKQ VKQ_C[ DV/(2*T_C_VKQ::J)];
#else // Volta
T_C_VKQ VKQ_C[ DV/(2*T_C_VKQ::J)];
#endif // defined(TURING_MMA_AVAILABLE)
@ -1010,6 +1124,10 @@ static __device__ __forceinline__ void flash_attn_ext_f16_process_tile(
// The partial sums are spread across 8/4 threads.
constexpr int offset_first = cols_per_warp == 8 ? 16 : 2;
constexpr int offset_last = cols_per_warp == 8 ? 4 : 1;
#elif defined(AMD_WMMA_AVAILABLE)
// The partial sums are spread across 2 threads.
constexpr int offset_first = 16;
constexpr int offset_last = 16;
#else // Volta
// The partial sums are spread across 2 threads.
constexpr int offset_first = 2;
@ -1047,7 +1165,7 @@ static __device__ __forceinline__ void flash_attn_ext_f16_process_tile(
#if defined(TURING_MMA_AVAILABLE)
if constexpr (cols_per_warp == 8) {
const half2 KQ_max_scale_h2 = make_half2(KQ_max_scale[0], KQ_max_scale[1]);
const half2 KQ_max_scale_h2 = make_half2(KQ_max_scale[0], KQ_max_scale[cols_per_thread - 1]);
#pragma unroll
for (int i = 0; i < DV/T_C_VKQ::I; ++i) {
#pragma unroll
@ -1068,6 +1186,15 @@ static __device__ __forceinline__ void flash_attn_ext_f16_process_tile(
}
}
}
#elif defined(AMD_WMMA_AVAILABLE)
const half2 KQ_max_scale_h2 = make_half2(KQ_max_scale[0], KQ_max_scale[0]);
#pragma unroll
for (int i = 0; i < (DV/2)/T_C_VKQ::J; ++i) {
#pragma unroll
for (int l = 0; l < T_C_VKQ::ne; ++l) {
VKQ_C[i].x[l] *= KQ_max_scale_h2;
}
}
#else // Volta
const int col = (threadIdx.x / 2) % 2;
const half2 KQ_max_scale_h2 = make_half2(KQ_max_scale[col], KQ_max_scale[col]);
@ -1119,6 +1246,10 @@ static __device__ __forceinline__ void flash_attn_ext_f16_process_tile(
const int jc_cwm = threadIdx.y*cols_per_warp + T_C_VKQ::get_i(threadIdx.x % 4);
const float2 KQ_cmr = make_float2(KQ_max[threadIdx.x % cols_per_thread], KQ_rowsum[threadIdx.x % cols_per_thread]);
const bool thread_should_write = threadIdx.x % 4 < cols_per_thread;
#elif defined(AMD_WMMA_AVAILABLE)
const int jc_cwm = threadIdx.y*cols_per_warp + T_C_VKQ::get_i(0);
const float2 KQ_cmr = make_float2(KQ_max[0], KQ_rowsum[0]);
const bool thread_should_write = threadIdx.x / 16 < cols_per_thread;
#else // Volta
const int jc_cwm = threadIdx.y*cols_per_warp + T_C_KQ::get_i(threadIdx.x & 2);
const float2 KQ_cmr = make_float2(KQ_max[(threadIdx.x & 2) / 2], KQ_rowsum[(threadIdx.x & 2) / 2]);
@ -1319,7 +1450,7 @@ static __device__ __forceinline__ void flash_attn_ext_f16_process_tile(
stride_Q1, stride_Q2, stride_K, stride_V, stride_mask,
jt, kb0_start, kb0_stop);
NO_DEVICE_CODE;
#endif // defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE)
#endif // defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE) || (defined(AMD_WMMA_AVAILABLE) && defined(RDNA4))
}
template<int DKQ, int DV, int ncols1, int ncols2, bool use_logit_softcap, bool mla>
@ -1346,7 +1477,7 @@ static __global__ void flash_attn_ext_f16(
const int32_t nb21, const int32_t nb22, const int64_t nb23,
const int32_t ne31, const int32_t ne32, const int32_t ne33,
const int32_t nb31, const int32_t nb32, const int64_t nb33) {
#if defined(FLASH_ATTN_AVAILABLE) && (defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE))
#if defined(FLASH_ATTN_AVAILABLE) && (defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE) || (defined(AMD_WMMA_AVAILABLE) && defined(RDNA4)))
// Skip unused kernel variants for faster compilation:
if (use_logit_softcap && !(DKQ == 128 || DKQ == 256)) {
@ -1360,6 +1491,13 @@ static __global__ void flash_attn_ext_f16(
}
#endif // __CUDA_ARCH__ == GGML_CUDA_CC_TURING
#if defined(AMD_WMMA_AVAILABLE)
if (ncols1*ncols2 > 32 || ncols1*ncols2 < 16 || DKQ > 128 || ncols2 == 1) {
NO_DEVICE_CODE;
return;
}
#endif // defined(AMD_WMMA_AVAILABLE)
static_assert(!mla || DKQ >= DV, "MLA needs DKQ >= DV");
constexpr int ncols = ncols1 * ncols2;
@ -1473,7 +1611,7 @@ static __global__ void flash_attn_ext_f16(
ne31, ne32, ne33,
nb31, nb32, nb33);
NO_DEVICE_CODE;
#endif // defined(FLASH_ATTN_AVAILABLE) && (defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE))
#endif // defined(FLASH_ATTN_AVAILABLE) && (defined(VOLTA_MMA_AVAILABLE) || defined(TURING_MMA_AVAILABLE) || (defined(AMD_WMMA_AVAILABLE) && defined(RDNA4)))
}
template <int DKQ, int DV, int ncols1, int ncols2>
@ -1492,7 +1630,7 @@ void ggml_cuda_flash_attn_ext_mma_f16_case(ggml_backend_cuda_context & ctx, ggml
const bool Q_in_reg = ggml_cuda_fattn_mma_get_Q_in_reg (DKQ, DV, ncols, cc);
const int nstages = ggml_cuda_fattn_mma_get_nstages (DKQ, DV, ncols1, ncols2, cc);
const int cols_per_warp = std::min(ncols, turing_mma_available(cc) ? 16 : 32);
const int cols_per_warp = std::min(ncols, get_cols_per_warp(cc));
const int nwarps = nthreads / WARP_SIZE;
constexpr bool mla = DKQ == 576;
@ -1512,29 +1650,34 @@ void ggml_cuda_flash_attn_ext_mma_f16_case(ggml_backend_cuda_context & ctx, ggml
float logit_softcap;
memcpy(&logit_softcap, (const float *) KQV->op_params + 2, sizeof(float));
#if defined(GGML_USE_HIP)
using fattn_kernel_ptr_t = const void*;
#else
using fattn_kernel_ptr_t = fattn_kernel_t;
#endif // defined(GGML_USE_HIP)
fattn_kernel_t fattn_kernel;
if (logit_softcap == 0.0f) {
constexpr bool use_logit_softcap = false;
fattn_kernel = flash_attn_ext_f16<DKQ, DV, ncols1, ncols2, use_logit_softcap, mla>;
#if !defined(GGML_USE_HIP) && !defined(GGML_USE_MUSA)
#if !defined(GGML_USE_MUSA)
static bool shared_memory_limit_raised[GGML_CUDA_MAX_DEVICES] = {false};
if (!shared_memory_limit_raised[id]) {
CUDA_CHECK(cudaFuncSetAttribute(fattn_kernel, cudaFuncAttributeMaxDynamicSharedMemorySize, nbytes_shared_total));
CUDA_CHECK(cudaFuncSetAttribute(reinterpret_cast<fattn_kernel_ptr_t>(fattn_kernel), cudaFuncAttributeMaxDynamicSharedMemorySize, nbytes_shared_total));
shared_memory_limit_raised[id] = true;
}
#endif // !defined(GGML_USE_HIP) && !defined(GGML_USE_MUSA)
#endif // !defined(GGML_USE_MUSA)
} else {
constexpr bool use_logit_softcap = true;
fattn_kernel = flash_attn_ext_f16<DKQ, DV, ncols1, ncols2, use_logit_softcap, mla>;
#if !defined(GGML_USE_HIP) && !defined(GGML_USE_MUSA)
#if !defined(GGML_USE_MUSA)
static bool shared_memory_limit_raised[GGML_CUDA_MAX_DEVICES] = {false};
if (!shared_memory_limit_raised[id]) {
CUDA_CHECK(cudaFuncSetAttribute(fattn_kernel, cudaFuncAttributeMaxDynamicSharedMemorySize, nbytes_shared_total));
CUDA_CHECK(cudaFuncSetAttribute(reinterpret_cast<fattn_kernel_ptr_t>(fattn_kernel), cudaFuncAttributeMaxDynamicSharedMemorySize, nbytes_shared_total));
shared_memory_limit_raised[id] = true;
}
#endif // !defined(GGML_USE_HIP) && !defined(GGML_USE_MUSA)
#endif // !defined(GGML_USE_MUSA)
}
launch_fattn<DV, ncols1, ncols2>

View File

@ -18,12 +18,12 @@ static void ggml_cuda_flash_attn_ext_mma_f16_switch_ncols1(ggml_backend_cuda_con
}
}
if (turing_mma_available(cc) && Q->ne[1] <= 16/ncols2) {
if ((turing_mma_available(cc) || amd_wmma_available(cc)) && Q->ne[1] <= 16/ncols2) {
ggml_cuda_flash_attn_ext_mma_f16_case<DKQ, DV, 16/ncols2, ncols2>(ctx, dst);
return;
}
if (ggml_cuda_highest_compiled_arch(cc) == GGML_CUDA_CC_TURING || Q->ne[1] <= 32/ncols2) {
if (ggml_cuda_highest_compiled_arch(cc) == GGML_CUDA_CC_TURING || amd_wmma_available(cc) || Q->ne[1] <= 32/ncols2) {
ggml_cuda_flash_attn_ext_mma_f16_case<DKQ, DV, 32/ncols2, ncols2>(ctx, dst);
return;
}
@ -230,7 +230,18 @@ static best_fattn_kernel ggml_cuda_get_best_fattn_kernel(const int device, const
// The effective batch size for the kernel can be increased by gqa_ratio.
// The kernel versions without this optimization are also used for ALiBi, if there is no mask, or if the KV cache is not padded,
const bool gqa_opt_applies = gqa_ratio % 2 == 0 && mask && max_bias == 0.0f && K->ne[1] % FATTN_KQ_STRIDE == 0;
bool gqa_opt_applies = gqa_ratio % 2 == 0 && mask && max_bias == 0.0f && K->ne[1] % FATTN_KQ_STRIDE == 0;
for (const ggml_tensor * t : {Q, K, V, mask}) {
if (t == nullptr) {
continue;
}
for (size_t i = 1; i < GGML_MAX_DIMS; ++i) {
if (t->nb[i] % 16 != 0) {
gqa_opt_applies = false;
break;
}
}
}
const int cc = ggml_cuda_info().devices[device].cc;
@ -337,6 +348,31 @@ static best_fattn_kernel ggml_cuda_get_best_fattn_kernel(const int device, const
return BEST_FATTN_KERNEL_WMMA_F16;
}
if (amd_wmma_available(cc) && GGML_CUDA_CC_IS_RDNA4(cc) && gqa_opt_applies && Q->ne[0] <= 128 && Q->ne[0] != 40 && Q->ne[0] != 72) {
if (can_use_vector_kernel) {
if (!ggml_is_quantized(K->type) && !ggml_is_quantized(V->type)) {
if (Q->ne[1] == 1) {
if (!gqa_opt_applies) {
return BEST_FATTN_KERNEL_VEC;
}
}
} else {
if (Q->ne[1] <= 2) {
return BEST_FATTN_KERNEL_VEC;
}
}
}
int gqa_ratio_eff = 1;
const int ncols2_max = Q->ne[0] == 576 ? 16 : 8;
while (gqa_ratio % (2*gqa_ratio_eff) == 0 && gqa_ratio_eff < ncols2_max) {
gqa_ratio_eff *= 2;
}
if (Q->ne[1] * gqa_ratio_eff <= 8) {
return BEST_FATTN_KERNEL_TILE; // AMD WMMA is only faster if the full tile width of 16 can be utilized.
}
return BEST_FATTN_KERNEL_MMA_F16;
}
// If there are no tensor cores available, use the generic tile kernel:
if (can_use_vector_kernel) {
if (!ggml_is_quantized(K->type) && !ggml_is_quantized(V->type)) {

View File

@ -206,10 +206,16 @@ namespace ggml_cuda_mma {
static __device__ __forceinline__ int get_j(const int l) {
if constexpr (I == 16 && J == 16) {
// matrix C
#if defined(RDNA3)
return 2 * l + (threadIdx.x / 16);
if constexpr (std::is_same_v<T, float> || std::is_same_v<T, int>) {
// matrix C
return 2 * l + (threadIdx.x / 16);
} else {
// matrix A&B
return l;
}
#else
// matrix C is the transposed matrix A&B on RDNA4
return ne * (threadIdx.x / 16) + l;
#endif // defined(RDNA3)
} else if constexpr (I == 16 && J == 8) {
@ -621,6 +627,21 @@ namespace ggml_cuda_mma {
return ret;
}
#elif defined(AMD_WMMA_AVAILABLE)
template <int I, int J>
static __device__ __forceinline__ tile<I, J/2, half2> get_half2(const tile<I, J, float> & tile_float) {
tile<I, J/2, half2> ret;
#pragma unroll
for (int l0 = 0; l0 < tile_float.ne; l0 += 2) {
ret.x[l0/2] = make_half2(tile_float.x[l0 + 0], tile_float.x[l0 + 1]);
}
return ret;
}
static __device__ __forceinline__ tile<8, 8, half2> get_transposed(const tile<16, 4, half2> & t) {
NO_DEVICE_CODE;
return tile<8, 8, half2>{};
}
#else // Volta
template <int I, int J>
static __device__ __forceinline__ tile<I, J/2, half2> get_half2(const tile<I, J, float> & tile_float) {
@ -639,6 +660,19 @@ namespace ggml_cuda_mma {
}
#endif // defined(TURING_MMA_AVAILABLE)
static __device__ __forceinline__ void make_identity_mat(tile<16, 8, half2> & t) {
#if defined(RDNA4)
const int row = t.get_i(0);
const int left_right = t.get_j(0) / 4;
const int up_down = row / 8;
const int idx = row % 8;
reinterpret_cast<half*>(t.x)[idx] = left_right == up_down ? 1.0f : 0.0f;
#else
GGML_UNUSED_VARS(t);
NO_DEVICE_CODE;
#endif // defined(RDNA4)
}
template <int I, int J, typename T, data_layout dl>
static __device__ __forceinline__ void load_generic(tile<I, J, T, dl> & t, const T * __restrict__ xs0, const int stride) {
#if defined(AMD_MFMA_AVAILABLE)
@ -878,6 +912,17 @@ namespace ggml_cuda_mma {
: "+r"(Dxi[2]), "+r"(Dxi[3])
: "r"(Axi[2]), "r"(Axi[3]), "r"(Bxi[3]));
#endif // __CUDA_ARCH__ >= GGML_CUDA_CC_AMPERE
#elif defined(AMD_WMMA_AVAILABLE)
#if defined(RDNA4)
using halfx8_t = __attribute__((ext_vector_type(8))) _Float16;
halfx8_t& acc_frag = reinterpret_cast<halfx8_t&>(D.x[0]);
const halfx8_t& a_frag = reinterpret_cast<const halfx8_t&>(A.x[0]);
const halfx8_t& b_frag = reinterpret_cast<const halfx8_t&>(B.x[0]);
acc_frag = __builtin_amdgcn_wmma_f16_16x16x16_f16_w32_gfx12(a_frag, b_frag, acc_frag);
#else
GGML_UNUSED_VARS(D, A, B);
NO_DEVICE_CODE;
#endif // defined(RDNA4)
#else
GGML_UNUSED_VARS(D, A, B);
NO_DEVICE_CODE;

View File

@ -138,6 +138,8 @@
#define cudaStream_t hipStream_t
#define cudaSuccess hipSuccess
#define cudaOccupancyMaxActiveBlocksPerMultiprocessor hipOccupancyMaxActiveBlocksPerMultiprocessor
#define cudaFuncSetAttribute hipFuncSetAttribute
#define cudaFuncAttributeMaxDynamicSharedMemorySize hipFuncAttributeMaxDynamicSharedMemorySize
#define __trap() do { abort(); __builtin_unreachable(); } while(0)
#define CUBLAS_STATUS_SUCCESS HIPBLAS_STATUS_SUCCESS
#define CUBLAS_STATUS_NOT_INITIALIZED HIPBLAS_STATUS_NOT_INITIALIZED