}
GGML_CALL static bool ggml_backend_cuda_supports_op(ggml_backend_t backend, const ggml_tensor * op) {
+ ggml_backend_cuda_context * cuda_ctx = (ggml_backend_cuda_context *) backend->context;
switch (op->op) {
case GGML_OP_UNARY:
switch (ggml_get_unary_op(op)) {
case GGML_OP_ARANGE:
case GGML_OP_TIMESTEP_EMBEDDING:
case GGML_OP_LEAKY_RELU:
- case GGML_OP_FLASH_ATTN_EXT:
return true;
+ case GGML_OP_FLASH_ATTN_EXT:
+#if defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__)
+ return op->src[0]->ne[0] == 64 || op->src[0]->ne[0] == 128;
+#else
+ if (op->src[0]->ne[0] == 64 || op->src[0]->ne[0] == 128) {
+ return true;
+ }
+ return ggml_cuda_info().devices[cuda_ctx->device].cc >= CC_VOLTA;
+#endif // defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__)
default:
return false;
}
#define FP16_MMA_AVAILABLE !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__)) && __CUDA_ARCH__ >= CC_VOLTA
+static bool fast_fp16_available(const int cc) {
+ return cc >= CC_PASCAL && cc != 610;
+}
+
static bool fp16_mma_available(const int cc) {
return cc < CC_OFFSET_AMD && cc >= CC_VOLTA;
}
--- /dev/null
+#define FATTN_KQ_STRIDE 256
+#define HALF_MAX_HALF __float2half(65504.0f/2) // Use neg. of this instead of -INFINITY to initialize KQ max vals to avoid NaN upon subtraction.
+#define SOFTMAX_FTZ_THRESHOLD -20.0f // Softmax exp. of values smaller than this are flushed to zero to avoid NaNs.
+
+template<int D, int parallel_blocks> // D == head size
+#if !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
+__launch_bounds__(D, 1)
+#endif // !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
+static __global__ void flash_attn_combine_results(
+ const float * __restrict__ VKQ_parts,
+ const float2 * __restrict__ VKQ_meta,
+ float * __restrict__ dst) {
+ VKQ_parts += parallel_blocks*D * gridDim.y*blockIdx.x;
+ VKQ_meta += parallel_blocks * gridDim.y*blockIdx.x;
+ dst += D * gridDim.y*blockIdx.x;
+
+ const int tid = threadIdx.x;
+ __builtin_assume(tid < D);
+
+ __shared__ float2 meta[parallel_blocks];
+ if (tid < 2*parallel_blocks) {
+ ((float *) meta)[threadIdx.x] = ((const float *)VKQ_meta) [blockIdx.y*(2*parallel_blocks) + tid];
+ }
+
+ __syncthreads();
+
+ float kqmax = meta[0].x;
+#pragma unroll
+ for (int l = 1; l < parallel_blocks; ++l) {
+ kqmax = max(kqmax, meta[l].x);
+ }
+
+ float VKQ_numerator = 0.0f;
+ float VKQ_denominator = 0.0f;
+#pragma unroll
+ for (int l = 0; l < parallel_blocks; ++l) {
+ const float diff = meta[l].x - kqmax;
+ const float KQ_max_scale = expf(diff);
+ const uint32_t ftz_mask = 0xFFFFFFFF * (diff > SOFTMAX_FTZ_THRESHOLD);
+ *((uint32_t *) &KQ_max_scale) &= ftz_mask;
+
+ VKQ_numerator += KQ_max_scale * VKQ_parts[l*gridDim.y*D + blockIdx.y*D + tid];
+ VKQ_denominator += KQ_max_scale * meta[l].y;
+ }
+
+ dst[blockIdx.y*D + tid] = VKQ_numerator / VKQ_denominator;
+}
--- /dev/null
+#include "common.cuh"
+#include "fattn-common.cuh"
+#include "fattn-vec-f16.cuh"
+
+template<int D, int ncols, int parallel_blocks> // D == head size
+#if !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
+__launch_bounds__(D, 1)
+#endif // !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
+static __global__ void flash_attn_vec_ext_f16(
+ const char * __restrict__ Q,
+ const char * __restrict__ K,
+ const char * __restrict__ V,
+ const char * __restrict__ mask,
+ float * __restrict__ dst,
+ float2 * __restrict__ dst_meta,
+ const float scale,
+ const float max_bias,
+ const float m0,
+ const float m1,
+ const uint32_t n_head_log2,
+ const int ne00,
+ const int ne01,
+ const int ne02,
+ const int ne03,
+ const int ne10,
+ const int ne11,
+ const int ne12,
+ const int ne13,
+ const int ne31,
+ const int nb31,
+ const int nb01,
+ const int nb02,
+ const int nb03,
+ const int nb11,
+ const int nb12,
+ const int nb13,
+ const int ne0,
+ const int ne1,
+ const int ne2,
+ const int ne3) {
+#if FP16_AVAILABLE
+ //In this kernel Q, K, V are matrices while i, j, k are matrix indices.
+
+ const int ic0 = (blockIdx.x / parallel_blocks) * ncols; // Index of the Q/QKV column to work on.
+ const int ip = blockIdx.x % parallel_blocks; // Index in group of blocks running for the same column in parallel.
+
+ const int gqa_ratio = ne02 / ne12; // With grouped query attention there are > 1 Q matrices per K, V matrix.
+ const float2 * Q_f2 = (const float2 *) (Q + nb02* blockIdx.y + nb01*ic0);
+ const half2 * K_h2 = (const half2 *) (K + nb12*(blockIdx.y / gqa_ratio));
+ const half * V_h = (const half *) (V + nb12*(blockIdx.y / gqa_ratio)); // K and V have same shape
+ const half * maskh = (const half *) mask + ne11*ic0;
+
+ const int stride_KV = nb11 / sizeof(half);
+ const int stride_KV2 = nb11 / sizeof(half2);
+
+ half slopeh = __float2half(1.0f);
+
+ // ALiBi
+ if (max_bias > 0.0f) {
+ const int h = blockIdx.y;
+
+ const float base = h < n_head_log2 ? m0 : m1;
+ const int exph = h < n_head_log2 ? h + 1 : 2*(h - n_head_log2) + 1;
+
+ slopeh = __float2half(powf(base, exph));
+ }
+
+ static_assert(D % (2*WARP_SIZE) == 0, "D not divisible by 2*WARP_SIZE == 64.");
+ constexpr int nwarps = D / WARP_SIZE;
+ const int tid = WARP_SIZE*threadIdx.y + threadIdx.x;
+ __builtin_assume(tid < D);
+
+ __shared__ half KQ[ncols*D];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ KQ[j*D + tid] = -HALF_MAX_HALF;
+ }
+ half2 * KQ2 = (half2 *) KQ;
+
+ half kqmax[ncols];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ kqmax[j] = -HALF_MAX_HALF;
+ }
+ half kqsum[ncols] = {0.0f};
+
+ __shared__ half kqmax_shared[ncols][WARP_SIZE];
+ __shared__ half kqsum_shared[ncols][WARP_SIZE];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ if (threadIdx.y == 0) {
+ kqmax_shared[j][threadIdx.x] = -HALF_MAX_HALF;
+ kqsum_shared[j][threadIdx.x] = 0.0f;
+ }
+ }
+ __syncthreads();
+
+ // Convert Q to half2 and store in registers:
+ half2 Q_h2[ncols][D/(2*WARP_SIZE)];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+#pragma unroll
+ for (int i0 = 0; i0 < D/2; i0 += WARP_SIZE) {
+ const int i = i0 + threadIdx.x;
+
+ const float2 tmp = Q_f2[j*(nb01/sizeof(float2)) + i];
+ Q_h2[j][i0/WARP_SIZE] = make_half2(scale, scale) * make_half2(tmp.x, tmp.y);
+ }
+ }
+
+ half2 VKQ[ncols] = {{0.0f, 0.0f}};
+
+ const int k_start = parallel_blocks == 1 ? 0 : ip*D;
+ for (int k_VKQ_0 = k_start; k_VKQ_0 < ne11; k_VKQ_0 += parallel_blocks*D) {
+ // Calculate KQ tile and keep track of new maximum KQ values:
+
+ // For unknown reasons using a half array of size 1 for kqmax_new causes a performance regression,
+ // see https://github.com/ggerganov/llama.cpp/pull/7061 .
+ // Therefore this variable is defined twice but only used once (so that the compiler can optimize out the unused variable).
+ half kqmax_new = kqmax[0];
+ half kqmax_new_arr[ncols];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ kqmax_new_arr[j] = kqmax[j];
+ }
+
+#pragma unroll
+ for (int i_KQ_0 = 0; i_KQ_0 < D; i_KQ_0 += nwarps) {
+ const int i_KQ = i_KQ_0 + threadIdx.y;
+
+ if ((i_KQ_0 + nwarps > D && i_KQ >= D) || (FATTN_KQ_STRIDE % D != 0 && k_VKQ_0 + i_KQ >= ne11)) {
+ break;
+ }
+
+ half2 sum2[ncols] = {{0.0f, 0.0f}};
+#pragma unroll
+ for (int k_KQ_0 = 0; k_KQ_0 < D/2; k_KQ_0 += WARP_SIZE) {
+ const int k_KQ = k_KQ_0 + threadIdx.x;
+
+ const half2 K_ik = K_h2[(k_VKQ_0 + i_KQ)*stride_KV2 + k_KQ];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ sum2[j] += K_ik * Q_h2[j][k_KQ_0/WARP_SIZE];
+ }
+ }
+
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ sum2[j] = warp_reduce_sum(sum2[j]);
+ half sum = __low2half(sum2[j]) + __high2half(sum2[j]);
+ sum += mask ? slopeh*maskh[j*ne11 + k_VKQ_0 + i_KQ] : __float2half(0.0f);
+
+ if (ncols == 1) {
+ kqmax_new = ggml_cuda_hmax(kqmax_new, sum);
+ } else {
+ kqmax_new_arr[j] = ggml_cuda_hmax(kqmax_new_arr[j], sum);
+ }
+
+ if (threadIdx.x == 0) {
+ KQ[j*D + i_KQ] = sum;
+ }
+ }
+ }
+
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ half kqmax_new_j = ncols == 1 ? kqmax_new : kqmax_new_arr[j];
+
+ kqmax_new_j = warp_reduce_max(kqmax_new_j);
+ if (threadIdx.x == 0) {
+ kqmax_shared[j][threadIdx.y] = kqmax_new_j;
+ }
+ }
+
+ __syncthreads();
+
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ half kqmax_new_j = kqmax_shared[j][threadIdx.x];
+ kqmax_new_j = warp_reduce_max(kqmax_new_j);
+
+ const half KQ_max_scale = hexp(kqmax[j] - kqmax_new_j);
+ kqmax[j] = kqmax_new_j;
+
+ const half val = hexp(KQ[j*D + tid] - kqmax[j]);
+ kqsum[j] = kqsum[j]*KQ_max_scale + val;
+ KQ[j*D + tid] = val;
+
+ VKQ[j] *= __half2half2(KQ_max_scale);
+ }
+
+ __syncthreads();
+
+#pragma unroll
+ for (int k0 = 0; k0 < D; k0 += 2) {
+ if (FATTN_KQ_STRIDE % D != 0 && k_VKQ_0 + k0 >= ne11) {
+ break;
+ }
+
+ half2 V_k;
+ reinterpret_cast<half&>(V_k.x) = V_h[(k_VKQ_0 + k0 + 0)*stride_KV + tid];
+ reinterpret_cast<half&>(V_k.y) = V_h[(k_VKQ_0 + k0 + 1)*stride_KV + tid];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ VKQ[j] += V_k*KQ2[j*(D/2) + k0/2];
+ }
+ }
+
+ __syncthreads();
+ }
+
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ kqsum[j] = warp_reduce_sum(kqsum[j]);
+ if (threadIdx.x == 0) {
+ kqsum_shared[j][threadIdx.y] = kqsum[j];
+ }
+ }
+
+ __syncthreads();
+
+#pragma unroll
+ for (int j_VKQ = 0; j_VKQ < ncols; ++j_VKQ) {
+ kqsum[j_VKQ] = kqsum_shared[j_VKQ][threadIdx.x];
+ kqsum[j_VKQ] = warp_reduce_sum(kqsum[j_VKQ]);
+
+ half dst_val = (__low2half(VKQ[j_VKQ]) + __high2half(VKQ[j_VKQ]));
+ if (parallel_blocks == 1) {
+ dst_val /= kqsum[j_VKQ];
+ }
+ const int j_dst = (ic0 + j_VKQ)*parallel_blocks + ip;
+ dst[j_dst*D*gridDim.y + D*blockIdx.y + tid] = dst_val;
+ }
+
+ if (parallel_blocks != 1 && tid != 0) {
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ dst_meta[(ic0 + j)*gridDim.y*parallel_blocks + blockIdx.y*parallel_blocks + ip] = make_float2(kqmax[j], kqsum[j]);
+ }
+ }
+#else
+ NO_DEVICE_CODE;
+#endif // FP16_AVAILABLE
+}
+
+template <int D, int cols_per_block, int parallel_blocks> void launch_fattn_vec_f16(
+ const ggml_tensor * Q, const ggml_tensor * K, const ggml_tensor * V, ggml_tensor * KQV, const ggml_tensor * mask,
+ ggml_cuda_pool & pool, cudaStream_t main_stream
+) {
+ ggml_cuda_pool_alloc<float> dst_tmp(pool);
+ ggml_cuda_pool_alloc<float2> dst_tmp_meta(pool);
+
+ if (parallel_blocks > 1) {
+ dst_tmp.alloc(parallel_blocks*ggml_nelements(KQV));
+ dst_tmp_meta.alloc(parallel_blocks*ggml_nrows(KQV));
+ }
+
+ constexpr int nwarps = (D + WARP_SIZE - 1) / WARP_SIZE;
+ const dim3 block_dim(WARP_SIZE, nwarps, 1);
+ const dim3 blocks_num(parallel_blocks*((Q->ne[1] + cols_per_block - 1) / cols_per_block), Q->ne[2], Q->ne[3]);
+ const int shmem = 0;
+
+ float scale = 1.0f;
+ float max_bias = 0.0f;
+
+ memcpy(&scale, (float *) KQV->op_params + 0, sizeof(float));
+ memcpy(&max_bias, (float *) KQV->op_params + 1, sizeof(float));
+
+ const uint32_t n_head = Q->ne[2];
+ const uint32_t n_head_log2 = 1u << (uint32_t) floorf(log2f((float) n_head));
+
+ const float m0 = powf(2.0f, -(max_bias ) / n_head_log2);
+ const float m1 = powf(2.0f, -(max_bias / 2.0f) / n_head_log2);
+
+ flash_attn_vec_ext_f16<D, cols_per_block, parallel_blocks>
+ <<<blocks_num, block_dim, shmem, main_stream>>> (
+ (const char *) Q->data,
+ (const char *) K->data,
+ (const char *) V->data,
+ mask ? ((const char *) mask->data) : nullptr,
+ parallel_blocks == 1 ? (float *) KQV->data : dst_tmp.ptr, dst_tmp_meta.ptr,
+ scale, max_bias, m0, m1, n_head_log2,
+ Q->ne[0], Q->ne[1], Q->ne[2], Q->ne[3],
+ K->ne[0], K->ne[1], K->ne[2], K->ne[3],
+ mask ? mask->ne[1] : 0, mask ? mask->nb[1] : 0,
+ Q->nb[1], Q->nb[2], Q->nb[3],
+ K->nb[1], K->nb[2], K->nb[3],
+ KQV->ne[0], KQV->ne[1], KQV->ne[2], KQV->ne[3]
+ );
+ CUDA_CHECK(cudaGetLastError());
+
+ if (parallel_blocks == 1) {
+ return;
+ }
+
+ const dim3 block_dim_combine(D, 1, 1);
+ const dim3 blocks_num_combine(Q->ne[1], blocks_num.y, blocks_num.z);
+ const int shmem_combine = 0;
+
+ flash_attn_combine_results<D, parallel_blocks>
+ <<<blocks_num_combine, block_dim_combine, shmem_combine, main_stream>>>
+ (dst_tmp.ptr, dst_tmp_meta.ptr, (float *) KQV->data);
+ CUDA_CHECK(cudaGetLastError());
+}
+
+void ggml_cuda_flash_attn_ext_vec_f16(ggml_backend_cuda_context & ctx, ggml_tensor * dst) {
+ const ggml_tensor * Q = dst->src[0];
+ const ggml_tensor * K = dst->src[1];
+ const ggml_tensor * V = dst->src[2];
+
+ const ggml_tensor * mask = dst->src[3];
+
+ ggml_tensor * KQV = dst;
+
+ const int32_t precision = KQV->op_params[2];
+ GGML_ASSERT(precision == GGML_PREC_DEFAULT);
+
+ constexpr int cols_per_block = 1;
+ constexpr int parallel_blocks = 4;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 256:
+ launch_fattn_vec_f16<256, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+}
+
+void ggml_cuda_flash_attn_ext_vec_f16_no_mma(ggml_backend_cuda_context & ctx, ggml_tensor * dst) {
+ const ggml_tensor * Q = dst->src[0];
+ const ggml_tensor * K = dst->src[1];
+ const ggml_tensor * V = dst->src[2];
+
+ const ggml_tensor * mask = dst->src[3];
+
+ ggml_tensor * KQV = dst;
+
+ const int32_t precision = KQV->op_params[2];
+ GGML_ASSERT(precision == GGML_PREC_DEFAULT);
+ GGML_ASSERT(Q->ne[0] == 64 || Q->ne[0] == 128 && "FlashAttention without tensor cores only supports head sizes 64 and 128.");
+
+ if (Q->ne[1] == 1) {
+ constexpr int cols_per_block = 1;
+ constexpr int parallel_blocks = 4;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+ return;
+ }
+
+ if (Q->ne[1] == 2) {
+ constexpr int cols_per_block = 2;
+ constexpr int parallel_blocks = 4;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+ return;
+ }
+
+ if (Q->ne[1] <= 4) {
+ constexpr int cols_per_block = 4;
+ constexpr int parallel_blocks = 4;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+ return;
+ }
+
+ if (Q->ne[1] <= 8) {
+ constexpr int cols_per_block = 8;
+ constexpr int parallel_blocks = 4;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+ return;
+ }
+
+ constexpr int cols_per_block = 8;
+ constexpr int parallel_blocks = 1;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+}
--- /dev/null
+#include "common.cuh"
+
+void ggml_cuda_flash_attn_ext_vec_f16(ggml_backend_cuda_context & ctx, ggml_tensor * dst);
+
+void ggml_cuda_flash_attn_ext_vec_f16_no_mma(ggml_backend_cuda_context & ctx, ggml_tensor * dst);
--- /dev/null
+#include "common.cuh"
+#include "fattn-common.cuh"
+#include "fattn-vec-f32.cuh"
+
+template<int D, int ncols, int parallel_blocks> // D == head size
+#if !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
+__launch_bounds__(D, 1)
+#endif // !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
+static __global__ void flash_attn_vec_ext_f32(
+ const char * __restrict__ Q,
+ const char * __restrict__ K,
+ const char * __restrict__ V,
+ const char * __restrict__ mask,
+ float * __restrict__ dst,
+ float2 * __restrict__ dst_meta,
+ const float scale,
+ const float max_bias,
+ const float m0,
+ const float m1,
+ const uint32_t n_head_log2,
+ const int ne00,
+ const int ne01,
+ const int ne02,
+ const int ne03,
+ const int ne10,
+ const int ne11,
+ const int ne12,
+ const int ne13,
+ const int ne31,
+ const int nb31,
+ const int nb01,
+ const int nb02,
+ const int nb03,
+ const int nb11,
+ const int nb12,
+ const int nb13,
+ const int ne0,
+ const int ne1,
+ const int ne2,
+ const int ne3) {
+ //In this kernel Q, K, V are matrices while i, j, k are matrix indices.
+
+ const int ic0 = (blockIdx.x / parallel_blocks) * ncols; // Index of the Q/QKV column to work on.
+ const int ip = blockIdx.x % parallel_blocks; // Index in group of blocks running for the same column in parallel.
+
+ const int gqa_ratio = ne02 / ne12; // With grouped query attention there are > 1 Q matrices per K, V matrix.
+ const float2 * Q_f2 = (const float2 *) (Q + nb02* blockIdx.y + nb01*ic0);
+ const half2 * K_h2 = (const half2 *) (K + nb12*(blockIdx.y / gqa_ratio));
+ const half * V_h = (const half *) (V + nb12*(blockIdx.y / gqa_ratio)); // K and V have same shape
+ const half * maskh = (const half *) mask + ne11*ic0;
+
+ const int stride_KV = nb11 / sizeof(half);
+ const int stride_KV2 = nb11 / sizeof(half2);
+
+ float slope = 1.0f;
+
+ // ALiBi
+ if (max_bias > 0.0f) {
+ const int h = blockIdx.y;
+
+ const float base = h < n_head_log2 ? m0 : m1;
+ const int exph = h < n_head_log2 ? h + 1 : 2*(h - n_head_log2) + 1;
+
+ slope = powf(base, exph);
+ }
+
+ static_assert(D % (2*WARP_SIZE) == 0, "D not divisible by 2*WARP_SIZE == 64.");
+ constexpr int nwarps = D / WARP_SIZE;
+ const int tid = WARP_SIZE*threadIdx.y + threadIdx.x;
+ __builtin_assume(tid < D);
+
+ __shared__ float KQ[ncols*D];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ KQ[j*D + tid] = -FLT_MAX/2.0f;
+ }
+
+ float kqmax[ncols];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ kqmax[j] = -FLT_MAX/2.0f;
+ }
+ float kqsum[ncols] = {0.0f};
+
+ __shared__ float kqmax_shared[ncols][WARP_SIZE];
+ __shared__ float kqsum_shared[ncols][WARP_SIZE];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ if (threadIdx.y == 0) {
+ kqmax_shared[j][threadIdx.x] = -FLT_MAX/2.0f;
+ kqsum_shared[j][threadIdx.x] = 0.0f;
+ }
+ }
+ __syncthreads();
+
+ // Convert Q to half2 and store in registers:
+ float2 Q_h2[ncols][D/(2*WARP_SIZE)];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+#pragma unroll
+ for (int i0 = 0; i0 < D/2; i0 += WARP_SIZE) {
+ const int i = i0 + threadIdx.x;
+
+ Q_h2[j][i0/WARP_SIZE] = Q_f2[j*(nb01/sizeof(float2)) + i];
+ Q_h2[j][i0/WARP_SIZE].x *= scale;
+ Q_h2[j][i0/WARP_SIZE].y *= scale;
+ }
+ }
+
+ float VKQ[ncols] = {0.0f};
+
+ const int k_start = parallel_blocks == 1 ? 0 : ip*D;
+ for (int k_VKQ_0 = k_start; k_VKQ_0 < ne11; k_VKQ_0 += parallel_blocks*D) {
+ // Calculate KQ tile and keep track of new maximum KQ values:
+
+ float kqmax_new_arr[ncols];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ kqmax_new_arr[j] = kqmax[j];
+ }
+
+#pragma unroll
+ for (int i_KQ_0 = 0; i_KQ_0 < D; i_KQ_0 += nwarps) {
+ const int i_KQ = i_KQ_0 + threadIdx.y;
+
+ if ((i_KQ_0 + nwarps > D && i_KQ >= D) || (FATTN_KQ_STRIDE % D != 0 && k_VKQ_0 + i_KQ >= ne11)) {
+ break;
+ }
+
+ float sum[ncols] = {0.0f};
+#pragma unroll
+ for (int k_KQ_0 = 0; k_KQ_0 < D/2; k_KQ_0 += WARP_SIZE) {
+ const int k_KQ = k_KQ_0 + threadIdx.x;
+
+ const half2 K_ik = K_h2[(k_VKQ_0 + i_KQ)*stride_KV2 + k_KQ];
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ sum[j] += __low2float(K_ik) * Q_h2[j][k_KQ_0/WARP_SIZE].x;
+ sum[j] += __high2float(K_ik) * Q_h2[j][k_KQ_0/WARP_SIZE].y;
+ }
+ }
+
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ sum[j] = warp_reduce_sum(sum[j]);
+ sum[j] += mask ? slope*__half2float(maskh[j*ne11 + k_VKQ_0 + i_KQ]) : 0.0f;
+
+ kqmax_new_arr[j] = fmaxf(kqmax_new_arr[j], sum[j]);
+
+ if (threadIdx.x == 0) {
+ KQ[j*D + i_KQ] = sum[j];
+ }
+ }
+ }
+
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ float kqmax_new_j = kqmax_new_arr[j];
+
+ kqmax_new_j = warp_reduce_max(kqmax_new_j);
+ if (threadIdx.x == 0) {
+ kqmax_shared[j][threadIdx.y] = kqmax_new_j;
+ }
+ }
+
+ __syncthreads();
+
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ float kqmax_new_j = kqmax_shared[j][threadIdx.x];
+ kqmax_new_j = warp_reduce_max(kqmax_new_j);
+
+ const float KQ_max_scale = expf(kqmax[j] - kqmax_new_j);
+ kqmax[j] = kqmax_new_j;
+
+ const float val = expf(KQ[j*D + tid] - kqmax[j]);
+ kqsum[j] = kqsum[j]*KQ_max_scale + val;
+ KQ[j*D + tid] = val;
+
+ VKQ[j] *= KQ_max_scale;
+ }
+
+ __syncthreads();
+
+#pragma unroll
+ for (int k = 0; k < D; ++k) {
+ if (FATTN_KQ_STRIDE % D != 0 && k_VKQ_0 + k >= ne11) {
+ break;
+ }
+
+ const float V_ki = __half2float(V_h[(k_VKQ_0 + k)*stride_KV + tid]);
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ VKQ[j] += V_ki*KQ[j*D + k];
+ }
+ }
+
+ __syncthreads();
+ }
+
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ kqsum[j] = warp_reduce_sum(kqsum[j]);
+ if (threadIdx.x == 0) {
+ kqsum_shared[j][threadIdx.y] = kqsum[j];
+ }
+ }
+
+ __syncthreads();
+
+#pragma unroll
+ for (int j_VKQ = 0; j_VKQ < ncols; ++j_VKQ) {
+ kqsum[j_VKQ] = kqsum_shared[j_VKQ][threadIdx.x];
+ kqsum[j_VKQ] = warp_reduce_sum(kqsum[j_VKQ]);
+
+ float dst_val = VKQ[j_VKQ];
+ if (parallel_blocks == 1) {
+ dst_val /= kqsum[j_VKQ];
+ }
+ const int j_dst = (ic0 + j_VKQ)*parallel_blocks + ip;
+ dst[j_dst*D*gridDim.y + D*blockIdx.y + tid] = dst_val;
+ }
+
+ if (parallel_blocks != 1 && tid != 0) {
+#pragma unroll
+ for (int j = 0; j < ncols; ++j) {
+ dst_meta[(ic0 + j)*gridDim.y*parallel_blocks + blockIdx.y*parallel_blocks + ip] = make_float2(kqmax[j], kqsum[j]);
+ }
+ }
+}
+
+template <int D, int cols_per_block, int parallel_blocks> void launch_fattn_vec_f32(
+ const ggml_tensor * Q, const ggml_tensor * K, const ggml_tensor * V, ggml_tensor * KQV, const ggml_tensor * mask,
+ ggml_cuda_pool & pool, cudaStream_t main_stream
+) {
+ ggml_cuda_pool_alloc<float> dst_tmp(pool);
+ ggml_cuda_pool_alloc<float2> dst_tmp_meta(pool);
+
+ if (parallel_blocks > 1) {
+ dst_tmp.alloc(parallel_blocks*ggml_nelements(KQV));
+ dst_tmp_meta.alloc(parallel_blocks*ggml_nrows(KQV));
+ }
+
+ constexpr int nwarps = (D + WARP_SIZE - 1) / WARP_SIZE;
+ const dim3 block_dim(WARP_SIZE, nwarps, 1);
+ const dim3 blocks_num(parallel_blocks*((Q->ne[1] + cols_per_block - 1) / cols_per_block), Q->ne[2], Q->ne[3]);
+ const int shmem = 0;
+
+ float scale = 1.0f;
+ float max_bias = 0.0f;
+
+ memcpy(&scale, (float *) KQV->op_params + 0, sizeof(float));
+ memcpy(&max_bias, (float *) KQV->op_params + 1, sizeof(float));
+
+ const uint32_t n_head = Q->ne[2];
+ const uint32_t n_head_log2 = 1u << (uint32_t) floorf(log2f((float) n_head));
+
+ const float m0 = powf(2.0f, -(max_bias ) / n_head_log2);
+ const float m1 = powf(2.0f, -(max_bias / 2.0f) / n_head_log2);
+
+ flash_attn_vec_ext_f32<D, cols_per_block, parallel_blocks>
+ <<<blocks_num, block_dim, shmem, main_stream>>> (
+ (const char *) Q->data,
+ (const char *) K->data,
+ (const char *) V->data,
+ mask ? ((const char *) mask->data) : nullptr,
+ parallel_blocks == 1 ? (float *) KQV->data : dst_tmp.ptr, dst_tmp_meta.ptr,
+ scale, max_bias, m0, m1, n_head_log2,
+ Q->ne[0], Q->ne[1], Q->ne[2], Q->ne[3],
+ K->ne[0], K->ne[1], K->ne[2], K->ne[3],
+ mask ? mask->ne[1] : 0, mask ? mask->nb[1] : 0,
+ Q->nb[1], Q->nb[2], Q->nb[3],
+ K->nb[1], K->nb[2], K->nb[3],
+ KQV->ne[0], KQV->ne[1], KQV->ne[2], KQV->ne[3]
+ );
+ CUDA_CHECK(cudaGetLastError());
+
+ if (parallel_blocks == 1) {
+ return;
+ }
+
+ const dim3 block_dim_combine(D, 1, 1);
+ const dim3 blocks_num_combine(Q->ne[1], blocks_num.y, blocks_num.z);
+ const int shmem_combine = 0;
+
+ flash_attn_combine_results<D, parallel_blocks>
+ <<<blocks_num_combine, block_dim_combine, shmem_combine, main_stream>>>
+ (dst_tmp.ptr, dst_tmp_meta.ptr, (float *) KQV->data);
+ CUDA_CHECK(cudaGetLastError());
+}
+
+void ggml_cuda_flash_attn_ext_vec_f32(ggml_backend_cuda_context & ctx, ggml_tensor * dst) {
+ const ggml_tensor * Q = dst->src[0];
+ const ggml_tensor * K = dst->src[1];
+ const ggml_tensor * V = dst->src[2];
+
+ const ggml_tensor * mask = dst->src[3];
+
+ ggml_tensor * KQV = dst;
+
+ GGML_ASSERT(Q->ne[0] == 64 || Q->ne[0] == 128 && "FlashAttention without tensor cores only supports head sizes 64 and 128.");
+
+ if (Q->ne[1] == 1) {
+ constexpr int cols_per_block = 1;
+ constexpr int parallel_blocks = 4;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f32< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f32<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+ return;
+ }
+
+ if (Q->ne[1] == 2) {
+ constexpr int cols_per_block = 2;
+ constexpr int parallel_blocks = 4;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f32< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f32<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+ return;
+ }
+
+ if (Q->ne[1] <= 4) {
+ constexpr int cols_per_block = 4;
+ constexpr int parallel_blocks = 4;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f32< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f32<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+ return;
+ }
+
+ if (Q->ne[1] <= 8) {
+ constexpr int cols_per_block = 8;
+ constexpr int parallel_blocks = 4;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f32< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f32<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+ return;
+ }
+
+ constexpr int cols_per_block = 8;
+ constexpr int parallel_blocks = 1;
+ switch (Q->ne[0]) {
+ case 64:
+ launch_fattn_vec_f32< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ case 128:
+ launch_fattn_vec_f32<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
+ break;
+ default:
+ GGML_ASSERT(false);
+ break;
+ }
+}
--- /dev/null
+#include "common.cuh"
+
+void ggml_cuda_flash_attn_ext_vec_f32(ggml_backend_cuda_context & ctx, ggml_tensor * dst);
#include "common.cuh"
+#include "fattn-common.cuh"
+#include "fattn-vec-f16.cuh"
+#include "fattn-vec-f32.cuh"
#include "fattn.cuh"
#include <cstdint>
#include <mma.h>
#endif
-#define FATTN_KQ_STRIDE 256
-#define HALF_MAX_HALF __float2half(65504.0f/2) // Use neg. of this instead of -INFINITY to initialize KQ max vals to avoid NaN upon subtraction.
-#define SOFTMAX_FTZ_THRESHOLD -20.0f // Softmax exp. of values smaller than this are flushed to zero to avoid NaNs.
-
-template<int D, int ncols, int parallel_blocks> // D == head size
-#if !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
-__launch_bounds__(D, 1)
-#endif // !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
-static __global__ void flash_attn_vec_ext_f16(
- const char * __restrict__ Q,
- const char * __restrict__ K,
- const char * __restrict__ V,
- const char * __restrict__ mask,
- float * __restrict__ dst,
- float2 * __restrict__ dst_meta,
- const float scale,
- const float max_bias,
- const float m0,
- const float m1,
- const uint32_t n_head_log2,
- const int ne00,
- const int ne01,
- const int ne02,
- const int ne03,
- const int ne10,
- const int ne11,
- const int ne12,
- const int ne13,
- const int ne31,
- const int nb31,
- const int nb01,
- const int nb02,
- const int nb03,
- const int nb11,
- const int nb12,
- const int nb13,
- const int ne0,
- const int ne1,
- const int ne2,
- const int ne3) {
-#if FP16_AVAILABLE
- //In this kernel Q, K, V are matrices while i, j, k are matrix indices.
-
- const int ic0 = (blockIdx.x / parallel_blocks) * ncols; // Index of the Q/QKV column to work on.
- const int ip = blockIdx.x % parallel_blocks; // Index in group of blocks running for the same column in parallel.
-
- const int gqa_ratio = ne02 / ne12; // With grouped query attention there are > 1 Q matrices per K, V matrix.
- const float2 * Q_f2 = (const float2 *) (Q + nb02* blockIdx.y + nb01*ic0);
- const half2 * K_h2 = (const half2 *) (K + nb12*(blockIdx.y / gqa_ratio));
- const half * V_h = (const half *) (V + nb12*(blockIdx.y / gqa_ratio)); // K and V have same shape
- const half * maskh = (const half *) mask + ne11*ic0;
-
- const int stride_KV = nb11 / sizeof(half);
- const int stride_KV2 = nb11 / sizeof(half2);
-
- half slopeh = __float2half(1.0f);
-
- // ALiBi
- if (max_bias > 0.0f) {
- const int h = blockIdx.y;
-
- const float base = h < n_head_log2 ? m0 : m1;
- const int exph = h < n_head_log2 ? h + 1 : 2*(h - n_head_log2) + 1;
-
- slopeh = __float2half(powf(base, exph));
- }
-
- static_assert(D % (2*WARP_SIZE) == 0, "D not divisible by 2*WARP_SIZE == 64.");
- constexpr int nwarps = D / WARP_SIZE;
- const int tid = WARP_SIZE*threadIdx.y + threadIdx.x;
- __builtin_assume(tid < D);
-
- __shared__ half KQ[ncols*D];
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- KQ[j*D + tid] = -HALF_MAX_HALF;
- }
- half2 * KQ2 = (half2 *) KQ;
-
- half kqmax[ncols];
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- kqmax[j] = -HALF_MAX_HALF;
- }
- half kqsum[ncols] = {0.0f};
-
- __shared__ half kqmax_shared[ncols][WARP_SIZE];
- __shared__ half kqsum_shared[ncols][WARP_SIZE];
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- if (threadIdx.y == 0) {
- kqmax_shared[j][threadIdx.x] = -HALF_MAX_HALF;
- kqsum_shared[j][threadIdx.x] = 0.0f;
- }
- }
- __syncthreads();
-
- // Convert Q to half2 and store in registers:
- half2 Q_h2[ncols][D/(2*WARP_SIZE)];
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
-#pragma unroll
- for (int i0 = 0; i0 < D/2; i0 += WARP_SIZE) {
- const int i = i0 + threadIdx.x;
-
- const float2 tmp = Q_f2[j*(nb01/sizeof(float2)) + i];
- Q_h2[j][i0/WARP_SIZE] = make_half2(scale, scale) * make_half2(tmp.x, tmp.y);
- }
- }
-
- half2 VKQ[ncols] = {{0.0f, 0.0f}};
-
- const int k_start = parallel_blocks == 1 ? 0 : ip*D;
- for (int k_VKQ_0 = k_start; k_VKQ_0 < ne11; k_VKQ_0 += parallel_blocks*D) {
- // Calculate KQ tile and keep track of new maximum KQ values:
-
- // For unknown reasons using a half array of size 1 for kqmax_new causes a performance regression,
- // see https://github.com/ggerganov/llama.cpp/pull/7061 .
- // Therefore this variable is defined twice but only used once (so that the compiler can optimize out the unused variable).
- half kqmax_new = kqmax[0];
- half kqmax_new_arr[ncols];
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- kqmax_new_arr[j] = kqmax[j];
- }
-
-#pragma unroll
- for (int i_KQ_0 = 0; i_KQ_0 < D; i_KQ_0 += nwarps) {
- const int i_KQ = i_KQ_0 + threadIdx.y;
-
- if ((i_KQ_0 + nwarps > D && i_KQ >= D) || (FATTN_KQ_STRIDE % D != 0 && k_VKQ_0 + i_KQ >= ne11)) {
- break;
- }
-
- half2 sum2[ncols] = {{0.0f, 0.0f}};
-#pragma unroll
- for (int k_KQ_0 = 0; k_KQ_0 < D/2; k_KQ_0 += WARP_SIZE) {
- const int k_KQ = k_KQ_0 + threadIdx.x;
-
- const half2 K_ik = K_h2[(k_VKQ_0 + i_KQ)*stride_KV2 + k_KQ];
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- sum2[j] += K_ik * Q_h2[j][k_KQ_0/WARP_SIZE];
- }
- }
-
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- sum2[j] = warp_reduce_sum(sum2[j]);
- half sum = __low2half(sum2[j]) + __high2half(sum2[j]);
- sum += mask ? slopeh*maskh[j*ne11 + k_VKQ_0 + i_KQ] : __float2half(0.0f);
-
- if (ncols == 1) {
- kqmax_new = ggml_cuda_hmax(kqmax_new, sum);
- } else {
- kqmax_new_arr[j] = ggml_cuda_hmax(kqmax_new_arr[j], sum);
- }
-
- if (threadIdx.x == 0) {
- KQ[j*D + i_KQ] = sum;
- }
- }
- }
-
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- half kqmax_new_j = ncols == 1 ? kqmax_new : kqmax_new_arr[j];
-
- kqmax_new_j = warp_reduce_max(kqmax_new_j);
- if (threadIdx.x == 0) {
- kqmax_shared[j][threadIdx.y] = kqmax_new_j;
- }
- }
-
- __syncthreads();
-
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- half kqmax_new_j = kqmax_shared[j][threadIdx.x];
- kqmax_new_j = warp_reduce_max(kqmax_new_j);
-
- const half KQ_max_scale = hexp(kqmax[j] - kqmax_new_j);
- kqmax[j] = kqmax_new_j;
-
- const half val = hexp(KQ[j*D + tid] - kqmax[j]);
- kqsum[j] = kqsum[j]*KQ_max_scale + val;
- KQ[j*D + tid] = val;
-
- VKQ[j] *= __half2half2(KQ_max_scale);
- }
-
- __syncthreads();
-
-#pragma unroll
- for (int k0 = 0; k0 < D; k0 += 2) {
- if (FATTN_KQ_STRIDE % D != 0 && k_VKQ_0 + k0 >= ne11) {
- break;
- }
-
- half2 V_k;
- reinterpret_cast<half&>(V_k.x) = V_h[(k_VKQ_0 + k0 + 0)*stride_KV + tid];
- reinterpret_cast<half&>(V_k.y) = V_h[(k_VKQ_0 + k0 + 1)*stride_KV + tid];
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- VKQ[j] += V_k*KQ2[j*(D/2) + k0/2];
- }
- }
-
- __syncthreads();
- }
-
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- kqsum[j] = warp_reduce_sum(kqsum[j]);
- if (threadIdx.x == 0) {
- kqsum_shared[j][threadIdx.y] = kqsum[j];
- }
- }
-
- __syncthreads();
-
-#pragma unroll
- for (int j_VKQ = 0; j_VKQ < ncols; ++j_VKQ) {
- kqsum[j_VKQ] = kqsum_shared[j_VKQ][threadIdx.x];
- kqsum[j_VKQ] = warp_reduce_sum(kqsum[j_VKQ]);
-
- half dst_val = (__low2half(VKQ[j_VKQ]) + __high2half(VKQ[j_VKQ]));
- if (parallel_blocks == 1) {
- dst_val /= kqsum[j_VKQ];
- }
- const int j_dst = (ic0 + j_VKQ)*parallel_blocks + ip;
- dst[j_dst*D*gridDim.y + D*blockIdx.y + tid] = dst_val;
- }
-
- if (parallel_blocks != 1 && tid != 0) {
-#pragma unroll
- for (int j = 0; j < ncols; ++j) {
- dst_meta[(ic0 + j)*gridDim.y*parallel_blocks + blockIdx.y*parallel_blocks + ip] = make_float2(kqmax[j], kqsum[j]);
- }
- }
-#else
- NO_DEVICE_CODE;
-#endif // FP16_AVAILABLE
-}
-
// D == head size, VKQ_stride == num VKQ rows calculated in parallel:
template<int D, int ncols, int nwarps, int VKQ_stride, int parallel_blocks, typename KQ_acc_t>
#if !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
#endif // FP16_MMA_AVAILABLE
}
-template<int D, int parallel_blocks> // D == head size
-#if !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
-__launch_bounds__(D, 1)
-#endif // !(defined(GGML_USE_HIPBLAS) && defined(__HIP_PLATFORM_AMD__))
-static __global__ void flash_attn_combine_results(
- const float * __restrict__ VKQ_parts,
- const float2 * __restrict__ VKQ_meta,
- float * __restrict__ dst) {
-#if FP16_AVAILABLE
- VKQ_parts += parallel_blocks*D * gridDim.y*blockIdx.x;
- VKQ_meta += parallel_blocks * gridDim.y*blockIdx.x;
- dst += D * gridDim.y*blockIdx.x;
-
- const int tid = threadIdx.x;
- __builtin_assume(tid < D);
-
- __shared__ float2 meta[parallel_blocks];
- if (tid < 2*parallel_blocks) {
- ((float *) meta)[threadIdx.x] = ((const float *)VKQ_meta) [blockIdx.y*(2*parallel_blocks) + tid];
- }
-
- __syncthreads();
-
- float kqmax = meta[0].x;
-#pragma unroll
- for (int l = 1; l < parallel_blocks; ++l) {
- kqmax = max(kqmax, meta[l].x);
- }
-
- float VKQ_numerator = 0.0f;
- float VKQ_denominator = 0.0f;
-#pragma unroll
- for (int l = 0; l < parallel_blocks; ++l) {
- const float diff = meta[l].x - kqmax;
- const float KQ_max_scale = expf(diff);
- const uint32_t ftz_mask = 0xFFFFFFFF * (diff > SOFTMAX_FTZ_THRESHOLD);
- *((uint32_t *) &KQ_max_scale) &= ftz_mask;
-
- VKQ_numerator += KQ_max_scale * VKQ_parts[l*gridDim.y*D + blockIdx.y*D + tid];
- VKQ_denominator += KQ_max_scale * meta[l].y;
- }
-
- dst[blockIdx.y*D + tid] = VKQ_numerator / VKQ_denominator;
-#else
- NO_DEVICE_CODE;
-#endif // FP16_AVAILABLE
-}
-
constexpr int get_max_power_of_2(int x) {
return x % 2 == 0 ? 2*get_max_power_of_2(x/2) : 1;
}
static_assert(get_VKQ_stride( 80, 2, 16) == 16, "Test failed.");
static_assert(get_VKQ_stride( 80, 4, 16) == 16, "Test failed.");
-template <int D, int cols_per_block, int parallel_blocks> void launch_fattn_vec_f16(
- const ggml_tensor * Q, const ggml_tensor * K, const ggml_tensor * V, ggml_tensor * KQV, const ggml_tensor * mask,
- ggml_cuda_pool & pool, cudaStream_t main_stream
-) {
- ggml_cuda_pool_alloc<float> dst_tmp(pool);
- ggml_cuda_pool_alloc<float2> dst_tmp_meta(pool);
-
- if (parallel_blocks > 1) {
- dst_tmp.alloc(parallel_blocks*ggml_nelements(KQV));
- dst_tmp_meta.alloc(parallel_blocks*ggml_nrows(KQV));
- }
-
- constexpr int nwarps = (D + WARP_SIZE - 1) / WARP_SIZE;
- const dim3 block_dim(WARP_SIZE, nwarps, 1);
- const dim3 blocks_num(parallel_blocks*((Q->ne[1] + cols_per_block - 1) / cols_per_block), Q->ne[2], Q->ne[3]);
- const int shmem = 0;
-
- float scale = 1.0f;
- float max_bias = 0.0f;
-
- memcpy(&scale, (float *) KQV->op_params + 0, sizeof(float));
- memcpy(&max_bias, (float *) KQV->op_params + 1, sizeof(float));
-
- const uint32_t n_head = Q->ne[2];
- const uint32_t n_head_log2 = 1u << (uint32_t) floorf(log2f((float) n_head));
-
- const float m0 = powf(2.0f, -(max_bias ) / n_head_log2);
- const float m1 = powf(2.0f, -(max_bias / 2.0f) / n_head_log2);
-
- flash_attn_vec_ext_f16<D, cols_per_block, parallel_blocks>
- <<<blocks_num, block_dim, shmem, main_stream>>> (
- (const char *) Q->data,
- (const char *) K->data,
- (const char *) V->data,
- mask ? ((const char *) mask->data) : nullptr,
- parallel_blocks == 1 ? (float *) KQV->data : dst_tmp.ptr, dst_tmp_meta.ptr,
- scale, max_bias, m0, m1, n_head_log2,
- Q->ne[0], Q->ne[1], Q->ne[2], Q->ne[3],
- K->ne[0], K->ne[1], K->ne[2], K->ne[3],
- mask ? mask->ne[1] : 0, mask ? mask->nb[1] : 0,
- Q->nb[1], Q->nb[2], Q->nb[3],
- K->nb[1], K->nb[2], K->nb[3],
- KQV->ne[0], KQV->ne[1], KQV->ne[2], KQV->ne[3]
- );
- CUDA_CHECK(cudaGetLastError());
-
- if (parallel_blocks == 1) {
- return;
- }
-
- const dim3 block_dim_combine(D, 1, 1);
- const dim3 blocks_num_combine(Q->ne[1], blocks_num.y, blocks_num.z);
- const int shmem_combine = 0;
-
- flash_attn_combine_results<D, parallel_blocks>
- <<<blocks_num_combine, block_dim_combine, shmem_combine, main_stream>>>
- (dst_tmp.ptr, dst_tmp_meta.ptr, (float *) KQV->data);
- CUDA_CHECK(cudaGetLastError());
-}
-
template <int D, int cols_per_block, int nwarps, int parallel_blocks, typename KQ_acc_t> void launch_fattn_f16_impl(
const ggml_tensor * Q, const ggml_tensor * K, const ggml_tensor * V, ggml_tensor * KQV, const ggml_tensor * mask,
ggml_cuda_pool & pool, cudaStream_t main_stream
const int32_t precision = KQV->op_params[2];
- if (!fp16_mma_available(cc)) {
- GGML_ASSERT(precision == GGML_PREC_DEFAULT);
- GGML_ASSERT(Q->ne[0] == 64 || Q->ne[0] == 128 && "FlashAttention without tensor cores only supports head sizes 64 and 128.");
-
- if (Q->ne[1] == 1) {
- constexpr int cols_per_block = 1;
- constexpr int parallel_blocks = 4;
- switch (Q->ne[0]) {
- case 64:
- launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- case 128:
- launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- default:
- GGML_ASSERT(false);
- break;
- }
- return;
- }
-
- if (Q->ne[1] == 2) {
- constexpr int cols_per_block = 2;
- constexpr int parallel_blocks = 4;
- switch (Q->ne[0]) {
- case 64:
- launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- case 128:
- launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- default:
- GGML_ASSERT(false);
- break;
- }
- return;
- }
-
- if (Q->ne[1] <= 4) {
- constexpr int cols_per_block = 4;
- constexpr int parallel_blocks = 4;
- switch (Q->ne[0]) {
- case 64:
- launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- case 128:
- launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- default:
- GGML_ASSERT(false);
- break;
- }
- return;
- }
-
- if (Q->ne[1] <= 8) {
- constexpr int cols_per_block = 8;
- constexpr int parallel_blocks = 4;
- switch (Q->ne[0]) {
- case 64:
- launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- case 128:
- launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- default:
- GGML_ASSERT(false);
- break;
- }
- return;
- }
+ if (!fast_fp16_available(cc)) {
+ ggml_cuda_flash_attn_ext_vec_f32(ctx, dst);
+ return;
+ }
- constexpr int cols_per_block = 8;
- constexpr int parallel_blocks = 1;
- switch (Q->ne[0]) {
- case 64:
- launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- case 128:
- launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- default:
- GGML_ASSERT(false);
- break;
- }
+ if (!fp16_mma_available(cc)) {
+ ggml_cuda_flash_attn_ext_vec_f16_no_mma(ctx, dst);
return;
}
if (precision != GGML_PREC_DEFAULT) {
+ if (Q->ne[1] == 1 && (Q->ne[0] == 64 || Q->ne[0] == 128)) {
+ ggml_cuda_flash_attn_ext_vec_f32(ctx, dst);
+ return;
+ }
+
if (Q->ne[1] <= 32 || Q->ne[0] > 128) {
constexpr int cols_per_block = 16;
constexpr int nwarps = 4;
}
if (Q->ne[1] == 1 && Q->ne[0] % (2*WARP_SIZE) == 0) {
- constexpr int cols_per_block = 1;
- constexpr int parallel_blocks = 4;
- switch (Q->ne[0]) {
- case 64:
- launch_fattn_vec_f16< 64, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- case 128:
- launch_fattn_vec_f16<128, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- case 256:
- launch_fattn_vec_f16<256, cols_per_block, parallel_blocks>(Q, K, V, KQV, mask, ctx.pool(), ctx.stream());
- break;
- default:
- GGML_ASSERT(false);
- break;
- }
+ ggml_cuda_flash_attn_ext_vec_f16(ctx, dst);
return;
}