diff --git a/ggml.c b/ggml.c index b75d55c3d..353b42cee 100644 --- a/ggml.c +++ b/ggml.c @@ -3336,6 +3336,7 @@ static const char * GGML_OP_LABEL[GGML_OP_COUNT] = { "FLASH_ATTN", "FLASH_FF", + "FLASH_ATTN_BACK", "MAP_UNARY", "MAP_BINARY", @@ -3344,7 +3345,7 @@ static const char * GGML_OP_LABEL[GGML_OP_COUNT] = { "CROSS_ENTROPY_LOSS_BACK", }; -static_assert(GGML_OP_COUNT == 55, "GGML_OP_COUNT != 55"); +static_assert(GGML_OP_COUNT == 56, "GGML_OP_COUNT != 56"); static const char * GGML_OP_SYMBOL[GGML_OP_COUNT] = { "none", @@ -3402,6 +3403,7 @@ static const char * GGML_OP_SYMBOL[GGML_OP_COUNT] = { "flash_attn(x)", "flash_ff(x)", + "flash_attn_back(x)", "f(x)", "f(x,y)", @@ -3410,7 +3412,7 @@ static const char * GGML_OP_SYMBOL[GGML_OP_COUNT] = { "cross_entropy_loss_back(x,y)", }; -static_assert(GGML_OP_COUNT == 55, "GGML_OP_COUNT != 55"); +static_assert(GGML_OP_COUNT == 56, "GGML_OP_COUNT != 56"); static_assert(sizeof(struct ggml_object)%GGML_MEM_ALIGN == 0, "ggml_object size must be a multiple of GGML_MEM_ALIGN"); static_assert(sizeof(struct ggml_tensor)%GGML_MEM_ALIGN == 0, "ggml_tensor size must be a multiple of GGML_MEM_ALIGN"); @@ -6251,7 +6253,6 @@ struct ggml_tensor * ggml_flash_ff( bool is_node = false; if (a->grad || b0->grad || b1->grad || c0->grad || c1->grad) { - GGML_ASSERT(false); // TODO: implement backward is_node = true; } @@ -6269,6 +6270,71 @@ struct ggml_tensor * ggml_flash_ff( return result; } +// ggml_flash_attn_back + +struct ggml_tensor * ggml_flash_attn_back( + struct ggml_context * ctx, + struct ggml_tensor * q, + struct ggml_tensor * k, + struct ggml_tensor * v, + struct ggml_tensor * d, + bool masked) { + GGML_ASSERT(ggml_can_mul_mat(k, q)); + // TODO: check if vT can be multiplied by (k*qT) + + // d shape [D,N,ne2,ne3] + // q shape [D,N,ne2,ne3] + // k shape [D,M,ne2,ne3] + // v shape [M,D,ne2,ne3] + + const int64_t D = q->ne[0]; + const int64_t N = q->ne[1]; + const int64_t M = k->ne[1]; + const int64_t ne2 = q->ne[2]; + const int64_t ne3 = q->ne[3]; + + GGML_ASSERT(k->ne[0] == D); + GGML_ASSERT(v->ne[0] == M); + GGML_ASSERT(v->ne[1] == D); + GGML_ASSERT(d->ne[0] == D); + GGML_ASSERT(d->ne[1] == N); + GGML_ASSERT(k->ne[2] == ne2); + GGML_ASSERT(k->ne[3] == ne3); + GGML_ASSERT(v->ne[2] == ne2); + GGML_ASSERT(v->ne[3] == ne3); + GGML_ASSERT(d->ne[2] == ne2); + GGML_ASSERT(d->ne[3] == ne3); + + bool is_node = false; + + if (q->grad || k->grad || v->grad) { + // when using this operation (in backwards pass) these grads are set. + // we don't want to create (big) grad of our result, so is_node is false. + is_node = false; + } + + // store gradients of q, k and v as continuous tensors concatenated in result. + // q shape[D,N,ne2,ne3] ; k shape [D,M,ne2,ne3] ; v shape [M,D,ne2,ne3] + // gradq->data = result->data + // gradk->data = result->data + nb0*D*N*ne2*ne3 + // gradv->data = result->data + nb0*D*N*ne2*ne3 + nb0*D*M*ne2*ne3 + // note: v and gradv are actually transposed, i.e. v->ne[0] != D. + int64_t ne[4] = {D,M+N+M,ne2,ne3}; + + struct ggml_tensor * result = ggml_new_tensor(ctx, GGML_TYPE_F32, 4, ne); + + result->op = GGML_OP_FLASH_ATTN_BACK; + result->grad = is_node ? ggml_dup_tensor(ctx, result) : NULL; + result->src0 = q; + result->src1 = k; + result->opt[0] = v; + result->opt[1] = d; + result->opt[2] = ggml_new_i32(ctx, masked ? 1 : 0); + + return result; +} + + // ggml_map_unary struct ggml_tensor * ggml_map_unary_impl_f32( @@ -12788,6 +12854,394 @@ static void ggml_compute_forward_flash_ff( } } +// ggml_compute_forward_flash_attn_back + +static void ggml_compute_forward_flash_attn_back_f32( + const struct ggml_compute_params * params, + const struct ggml_tensor * q, + const struct ggml_tensor * k, + const struct ggml_tensor * v, + const struct ggml_tensor * d, + const bool masked, + struct ggml_tensor * dst) { + int64_t t0 = ggml_perf_time_us(); + UNUSED(t0); + + const int64_t neq0 = q->ne[0]; + const int64_t neq1 = q->ne[1]; + const int64_t neq2 = q->ne[2]; + const int64_t neq3 = q->ne[3]; + + const int64_t nek0 = k->ne[0]; + const int64_t nek1 = k->ne[1]; + //const int64_t nek2 = k->ne[2]; + //const int64_t nek3 = k->ne[3]; + + const int64_t nev0 = v->ne[0]; + const int64_t nev1 = v->ne[1]; + //const int64_t nev2 = v->ne[2]; + //const int64_t nev3 = v->ne[3]; + + const int64_t ne0 = dst->ne[0]; + const int64_t ne1 = dst->ne[1]; + //const int64_t ne2 = dst->ne[2]; + //const int64_t ne3 = dst->ne[3]; + + const int nbk0 = k->nb[0]; + const int nbk1 = k->nb[1]; + const int nbk2 = k->nb[2]; + const int nbk3 = k->nb[3]; + + const int nbq0 = q->nb[0]; + const int nbq1 = q->nb[1]; + const int nbq2 = q->nb[2]; + const int nbq3 = q->nb[3]; + + const int nbv0 = v->nb[0]; + const int nbv1 = v->nb[1]; + const int nbv2 = v->nb[2]; + const int nbv3 = v->nb[3]; + + const int nbd0 = d->nb[0]; + const int nbd1 = d->nb[1]; + const int nbd2 = d->nb[2]; + const int nbd3 = d->nb[3]; + + const int nb0 = dst->nb[0]; + const int nb1 = dst->nb[1]; + const int nb2 = dst->nb[2]; + const int nb3 = dst->nb[3]; + + const int ith = params->ith; + const int nth = params->nth; + + const int64_t D = neq0; + const int64_t N = neq1; + const int64_t P = nek1 - N; + const int64_t M = P + N; + + const int Mup = ggml_up(M, GGML_SOFT_MAX_UNROLL); + const int mxDM = MAX(D, Mup); + + GGML_ASSERT(ne0 == D); + GGML_ASSERT(ne1 == N); + GGML_ASSERT(P >= 0); + + GGML_ASSERT(nbq0 == sizeof(float)); + GGML_ASSERT(nbk0 == sizeof(float)); + GGML_ASSERT(nbv0 == sizeof(float)); + + GGML_ASSERT(neq0 == D); + GGML_ASSERT(nek0 == D); + GGML_ASSERT(nev1 == D); + + GGML_ASSERT(neq1 == N); + GGML_ASSERT(nek1 == N + P); + GGML_ASSERT(nev1 == D); + + // dst cannot be transposed or permuted + GGML_ASSERT(nb0 == sizeof(float)); + GGML_ASSERT(nb0 <= nb1); + GGML_ASSERT(nb1 <= nb2); + GGML_ASSERT(nb2 <= nb3); + + if (params->type == GGML_TASK_INIT) { + return; + } + + if (params->type == GGML_TASK_FINALIZE) { + return; + } + + // parallelize by q rows using ggml_vec_dot_f32 + + // total rows in q + const int nr = neq1*neq2*neq3; + + // rows per thread + const int dr = (nr + nth - 1)/nth; + + // row range for this thread + const int ir0 = dr*ith; + const int ir1 = MIN(ir0 + dr, nr); + + const float scale = 1.0f/sqrtf(D); + + //printf("P=%d N=%d D=%d ir0=%d ir1=%d scale = %f\n", P, N, D, ir0, ir1, scale); + + for (int ir = ir0; ir < ir1; ++ir) { + // q indices + const int iq3 = ir/(neq2*neq1); + const int iq2 = (ir - iq3*neq2*neq1)/neq1; + const int iq1 = (ir - iq3*neq2*neq1 - iq2*neq1); + + // not sure about CACHE_LINE_SIZE_F32.. + // - maybe it must not be multiplied by 2 and excluded from .. in SM 1*(..) offset? + float * S = (float *) params->wdata + ith*2*(mxDM + CACHE_LINE_SIZE_F32) + 0*(mxDM+CACHE_LINE_SIZE_F32); + float * SM = (float *) params->wdata + ith*2*(mxDM + CACHE_LINE_SIZE_F32) + 1*(mxDM+CACHE_LINE_SIZE_F32); + + for (int i = M; i < Mup; ++i) { + S[i] = -INFINITY; + } + + for (int64_t ic = 0; ic < nek1; ++ic) { + // k indices + const int ik3 = iq3; + const int ik2 = iq2; + const int ik1 = ic; + + // S indices + const int i1 = ik1; + + ggml_vec_dot_f32(neq0, + S + i1, + (float *) ((char *) k->data + (ik1*nbk1 + ik2*nbk2 + ik3*nbk3)), + (float *) ((char *) q->data + (iq1*nbq1 + iq2*nbq2 + iq3*nbq3))); + } + + // scale + ggml_vec_scale_f32(nek1, S, scale); + + if (masked) { + for (int64_t i = P; i < M; i++) { + if (i > P + iq1) { + S[i] = -INFINITY; + } + } + } + + // softmax + { + float max = -INFINITY; + ggml_vec_max_f32(M, &max, S); + + ggml_float sum = 0.0; + { +#ifdef GGML_SOFT_MAX_ACCELERATE + max = -max; + vDSP_vsadd(SM, 1, &max, SM, 1, Mup); + vvexpf(SM, SM, &Mup); + ggml_vec_sum_f32(Mup, &sum, SM); +#else + uint16_t scvt[GGML_SOFT_MAX_UNROLL]; + ggml_float sump[GGML_SOFT_MAX_UNROLL] = { 0.0 }; + + for (int i = 0; i < Mup; i += GGML_SOFT_MAX_UNROLL) { + float * SS = SM + i; + + for (int j = 0; j < GGML_SOFT_MAX_UNROLL; ++j) { + if (SS[j] == -INFINITY) { + SS[j] = 0.0f; + } else { + ggml_fp16_t s = GGML_FP32_TO_FP16(SS[j] - max); + memcpy(&scvt[j], &s, sizeof(uint16_t)); + const float val = GGML_FP16_TO_FP32(table_exp_f16[scvt[j]]); + sump[j] += (ggml_float)val; + SS[j] = val; + } + } + } + + for (int i = 0; i < GGML_SOFT_MAX_UNROLL; i++) { + sum += sump[i]; + } +#endif + } + + assert(sum > 0.0); + + sum = 1.0/sum; + ggml_vec_scale_f32(M, SM, sum); + + } + + // step-by-step explanation + { + // forward-process shape grads from backward process + // parallel_for iq2,iq3: + // k[:D,:M,:,:] [D,M,:,:] grad[k][:D,:M,iq2,iq3] += grad[kcur] + // q[:D,:N,:,:] [D,N,:,:] grad[q][:D,iq1,iq2,iq3] += grad[qcur] + // v[:M,:D,:,:] [M,D,:,:] grad[v][:M,:D,iq2,iq3] += grad[vcur] + // for iq1: + // kcur = k[:D,:M,iq2,iq3] [D,M,1,1] grad[kcur] = grad[S1].T @ qcur + // qcur = q[:D,iq1,iq2,iq3] [D,1,1,1] grad[qcur] = grad[S1] @ kcur + // vcur = v[:M,:D,iq2,iq3] [M,D,1,1] grad[vcur] = grad[S5].T @ S4 + // S0 = -Inf [D,1,1,1] + // ~S1[i] = dot(kcur[:D,i], qcur) + // S1 = qcur.T @ kcur [M,1,1,1] grad[S1] = grad[S2] * scale + // S2 = S1 * scale [M,1,1,1] grad[S2] = diag_mask_zero(grad[S3], P) + // S3 = diag_mask_inf(S2, P) [M,1,1,1] grad[S3] = S4 * (grad[S4] - dot(S4, grad[S4])) + // S4 = softmax(S3) [M,1,1,1] grad[S4] = grad[S5] @ vcur + // ~S5[i] = dot(vcur[:,i],S4) + // S5 = S4.T @ vcur [D,1,1,1] grad[S5] = d[:D,iq1,iq2,iq3] + // ~dst[i,iq1,iq2,iq3] = S5[i] ^ + // dst[:D,iq1,iq2,iq3] = S5 | grad[dst[:D,iq1,iq2,iq3]] = d[:D,iq1,iq2,iq3] + // dst backward-/ grad[dst] = d + // + // output gradients with their dependencies: + // + // grad[kcur] = grad[S1].T @ qcur + // grad[S1] = diag_mask_zero(grad[S3], P) * scale + // grad[S3] = S4 * (grad[S4] - dot(S4, grad[S4])) + // grad[S4] = grad[S5] @ vcur + // grad[S4] = d[:D,iq1,iq2,iq3] @ vcur + // grad[qcur] = grad[S1] @ kcur + // grad[vcur] = grad[S5].T @ S4 + // grad[vcur] = d[:D,iq1,iq2,iq3].T @ S4 + // + // in post-order: + // + // S1 = qcur.T @ kcur + // S2 = S1 * scale + // S3 = diag_mask_inf(S2, P) + // S4 = softmax(S3) + // grad[S4] = d[:D,iq1,iq2,iq3] @ vcur + // grad[S3] = S4 * (grad[S4] - dot(S4, grad[S4])) + // grad[S1] = diag_mask_zero(grad[S3], P) * scale + // grad[qcur] = grad[S1] @ kcur + // grad[kcur] = grad[S1].T @ qcur + // grad[vcur] = d[:D,iq1,iq2,iq3].T @ S4 + // + // using less variables (SM=S4): + // + // S = diag_mask_inf(qcur.T @ kcur * scale, P) + // SM = softmax(S) + // S = d[:D,iq1,iq2,iq3] @ vcur + // dot_SM_gradSM = dot(SM, S) + // S = SM * (S - dot(SM, S)) + // S = diag_mask_zero(S, P) * scale + // + // grad[q][:D,iq1,iq2,iq3] += S @ kcur + // grad[k][:D,:M,iq2,iq3] += S.T @ qcur + // grad[v][:M,:D,iq2,iq3] += d[:D,iq1,iq2,iq3].T @ SM + } + + // S = gradSM = d[:D,iq1,iq2,iq3] @ vcur + // S = d[:D,iq1,iq2,iq3] @ vcur + // S[:M] += vcur[:,ic] * d[ic,iq1,iq2,iq3] + ggml_vec_set_f32(D, S, 0); + for (int64_t ic = 0; ic < D; ++ic) { + // dst indices + const int i1 = iq1; + const int i2 = iq2; + const int i3 = iq3; + + ggml_vec_mad_f32(M, + S, + (float *) ((char *) v->data + ( ic*nbv1 + i2*nbv2 + i3*nbv3)), + *(float *) ((char *) d->data + (ic*nbd1 + i1*nbd2 + i2*nbd2 + i3*nbd3))); + } + + // S = SM * (S - dot(SM, S)) + float dot_SM_gradSM = 0; + ggml_vec_dot_f32 (M, &dot_SM_gradSM, SM, S); + ggml_vec_acc1_f32(M, S, -dot_SM_gradSM); + ggml_vec_mul_f32 (M, S, S, SM); + + // S = diag_mask_zero(S, P) * scale + if (masked) { + for (int64_t i = P + iq1 + 1; i < M; i++) { + S[i] = 0; + } + } + ggml_vec_scale_f32(M, S, scale); + + void * grad_q = (char *) dst->data; + void * grad_k = (char *) dst->data + nb0*D*N*neq2*neq3; + void * grad_v = (char *) dst->data + nb0*D*N*neq2*neq3 + nb0*D*M*neq2*neq3; + + const size_t nbgq1 = nb0*neq0; + const size_t nbgq2 = nb0*neq0*neq1; + const size_t nbgq3 = nb0*neq0*neq1*neq2; + + const size_t nbgk1 = nb0*nek0; + const size_t nbgk2 = nb0*nek0*nek1; + const size_t nbgk3 = nb0*nek0*nek1*neq2; + + const size_t nbgv1 = nb0*nev0; + const size_t nbgv2 = nb0*nev0*nev1; + const size_t nbgv3 = nb0*nev0*nev1*neq2; + + // S shape [M,1] + // SM shape [M,1] + // kcur shape [D,M] + // qcur shape [D,1] + // vcur shape [M,D] + // + // grad[q][:D,iq1,iq2,iq3] += S @ kcur + // grad[q][:D,iq1,iq2,iq3] += shape[M,1] @ shape[D,M] + // grad[q][ic,iq1,iq2,iq3] += dot(kcur[:,ic],S.T) + // grad[q][ic,iq1,iq2,iq3] += dot(k[:D,ic,iq2,iq3],S.T) + for (int64_t ic = 0; ic < M; ++ic) { + // dst indices + const int i1 = iq1; + const int i2 = iq2; + const int i3 = iq3; + + ggml_vec_dot_f32(D, + (float *) ((char *) grad_q + (ic*nb0 + i1*nbgq1 + i2*nbgq2 + i3*nbgq3)), + (float *) ((char *) k->data + ( ic*nbk1 + i2*nbk2 + i3*nbk3)), + S); + } + + // grad[k][:D,:M,iq2,iq3] += S.T @ qcur + // grad[k][:D,ic,iq2,iq3] += S.T[0,ic] * qcur[:D,0] + // grad[k][:D,ic,iq2,iq3] += S[ic] * qcur[:D,0] + for (int64_t ic = 0; ic < M; ++ic) { + // dst indices + const int i1 = iq1; + const int i2 = iq2; + const int i3 = iq3; + + ggml_vec_set_f32(D, + (float *) ((char *) grad_k + (ic*nbgk1 + i2*nbgk2 + i3*nbgk3)), + 0); + ggml_vec_mad_f32(D, + (float *) ((char *) grad_k + (ic*nbgk1 + i2*nbgk2 + i3*nbgk3)), + (float *) ((char *) q->data + (i1*nbk1 + i2*nbk2 + i3*nbk3)), + S[ic]); + } + + // grad[v][:M,:D,iq2,iq3] += d[:D,iq1,iq2,iq3].T @ SM + // grad[v][:M,ic,iq2,iq3] += d[:D,iq1,iq2,iq3].T[0,ic] * SM[:M] + // grad[v][:M,ic,iq2,iq3] += d[ic,iq1,iq2,iq3] * SM[:M] + for (int64_t ic = 0; ic < D; ++ic) { + // dst indices + const int i1 = iq1; + const int i2 = iq2; + const int i3 = iq3; + + ggml_vec_set_f32(M, + (float *) ((char *) grad_v + ( ic*nbgv1 + i2*nbgv2 + i3*nbgv3)), + 0); + ggml_vec_mad_f32(M, + (float *) ((char *) grad_v + ( ic*nbgv1 + i2*nbgv2 + i3*nbgv3)), + SM, + *(float *) ((char *) d->data + (ic*nbd1 + i1*nbd2 + i2*nbd2 + i3*nbd3))); + } + } +} + +static void ggml_compute_forward_flash_attn_back( + const struct ggml_compute_params * params, + const struct ggml_tensor * q, + const struct ggml_tensor * k, + const struct ggml_tensor * v, + const struct ggml_tensor * d, + const bool masked, + struct ggml_tensor * dst) { + switch (q->type) { + case GGML_TYPE_F32: + { + ggml_compute_forward_flash_attn_back_f32(params, q, k, v, d, masked, dst); + } break; + default: + { + GGML_ASSERT(false); + } break; + } +} + // ggml_compute_forward_map_unary static void ggml_compute_forward_map_unary_f32( @@ -13371,6 +13825,13 @@ static void ggml_compute_forward(struct ggml_compute_params * params, struct ggm { ggml_compute_forward_flash_ff(params, tensor->src0, tensor->src1, tensor->opt[0], tensor->opt[1], tensor->opt[2], tensor); } break; + case GGML_OP_FLASH_ATTN_BACK: + { + int32_t t = ggml_get_i32_1d(tensor->opt[2], 0); + GGML_ASSERT(t == 0 || t == 1); + bool masked = t != 0; + ggml_compute_forward_flash_attn_back(params, tensor->src0, tensor->src1, tensor->opt[0], tensor->opt[1], masked, tensor); + } break; case GGML_OP_MAP_UNARY: { const ggml_unary_op_f32_t fun = *((ggml_unary_op_f32_t *)tensor->opt[0]->data); @@ -14007,12 +14468,169 @@ static void ggml_compute_backward(struct ggml_context * ctx, struct ggml_tensor } break; case GGML_OP_FLASH_ATTN: { - GGML_ASSERT(false); // not supported + struct ggml_tensor * flash_grad = NULL; + if (src0->grad || src1->grad || tensor->opt[0]->grad) { + int32_t t = ggml_get_i32_1d(tensor->opt[1], 0); + GGML_ASSERT(t == 0 || t == 1); + bool masked = t != 0; + flash_grad = + ggml_flash_attn_back(ctx, + src0->grad, + src1->grad, + tensor->opt[0]->grad, + tensor->grad, + masked); + } + + if (src0->grad) { + struct ggml_tensor * grad_q = NULL; + const size_t nb0 = flash_grad->nb[0]; + const size_t offset = 0; + switch(src0->n_dims) { + case 2: + { + grad_q = ggml_view_2d(ctx, + flash_grad, + src0->ne[0], + src0->ne[1], + nb0*src0->ne[0], + offset); + } break; + case 3: + { + grad_q = ggml_view_3d(ctx, + flash_grad, + src0->ne[0], + src0->ne[1], + src0->ne[2], + nb0*src0->ne[0], + nb0*src0->ne[0]*src0->ne[1], + offset); + } break; + case 4: + { + grad_q = ggml_view_3d(ctx, + flash_grad, + src0->ne[0], + src0->ne[1], + src0->ne[2], + src0->ne[3], + nb0*src0->ne[0], + nb0*src0->ne[0]*src0->ne[1], + nb0*src0->ne[0]*src0->ne[1]*src0->ne[2], + offset); + } break; + } + + src0->grad = ggml_add_impl(ctx, + src0->grad, + grad_q, + inplace); + } + + if (src1->grad) { + struct ggml_tensor * grad_k = NULL; + const size_t nb0 = flash_grad->nb[0]; + const size_t offset = nb0*src0->ne[0]*src0->ne[1]*src0->ne[2]*src0->ne[3]; + switch(src1->n_dims) { + case 2: + { + grad_k = ggml_view_2d(ctx, + flash_grad, + src1->ne[0], + src1->ne[1], + nb0*src1->ne[0], + offset); + } break; + case 3: + { + grad_k = ggml_view_3d(ctx, + flash_grad, + src1->ne[0], + src1->ne[1], + src1->ne[2], + nb0*src1->ne[0], + nb0*src1->ne[0]*src1->ne[1], + offset); + } break; + case 4: + { + grad_k = ggml_view_3d(ctx, + flash_grad, + src1->ne[0], + src1->ne[1], + src1->ne[2], + src1->ne[3], + nb0*src1->ne[0], + nb0*src1->ne[0]*src1->ne[1], + nb0*src1->ne[0]*src1->ne[1]*src1->ne[2], + offset); + } break; + } + + src1->grad = ggml_add_impl(ctx, + src1->grad, + grad_k, + inplace); + } + + struct ggml_tensor * opt0 = tensor->opt[0]; + + if (opt0->grad) { + struct ggml_tensor * grad_v = NULL; + const size_t nb0 = flash_grad->nb[0]; + const size_t offset = nb0*src0->ne[0]*src0->ne[1]*src0->ne[2]*src0->ne[3] + + nb0*src1->ne[0]*src1->ne[1]*src1->ne[2]*src1->ne[3]; + switch(opt0->n_dims) { + case 2: + { + grad_v = ggml_view_2d(ctx, + flash_grad, + opt0->ne[0], + opt0->ne[1], + nb0*opt0->ne[0], + offset); + } break; + case 3: + { + grad_v = ggml_view_3d(ctx, + flash_grad, + opt0->ne[0], + opt0->ne[1], + opt0->ne[2], + nb0*opt0->ne[0], + nb0*opt0->ne[0]*opt0->ne[1], + offset); + } break; + case 4: + { + grad_v = ggml_view_3d(ctx, + flash_grad, + opt0->ne[0], + opt0->ne[1], + opt0->ne[2], + opt0->ne[3], + nb0*opt0->ne[0], + nb0*opt0->ne[0]*opt0->ne[1], + nb0*opt0->ne[0]*opt0->ne[1]*opt0->ne[2], + offset); + } break; + } + + opt0->grad = ggml_add_impl(ctx, + opt0->grad, + grad_v, + inplace); + } } break; case GGML_OP_FLASH_FF: { GGML_ASSERT(false); // not supported } break; + case GGML_OP_FLASH_ATTN_BACK: + { + GGML_ASSERT(false); // not supported + } break; case GGML_OP_MAP_UNARY: case GGML_OP_MAP_BINARY: { @@ -14575,6 +15193,27 @@ void ggml_graph_compute(struct ggml_context * ctx, struct ggml_cgraph * cgraph) cur += sizeof(float)*node->src1->ne[1]*node->n_tasks; // this is overestimated by x2 } + work_size = MAX(work_size, cur); + } break; + case GGML_OP_FLASH_ATTN_BACK: + { + node->n_tasks = n_threads; + + size_t cur = 0; + + const int64_t D = node->src0->ne[0]; + const int64_t ne11 = ggml_up(node->src1->ne[1], GGML_SOFT_MAX_UNROLL); + const int64_t mxDn = MAX(D, ne11) * 2; // *2 because of S and SM in ggml_compute_forward_flash_attn_back + if (node->src1->type == GGML_TYPE_F32) { + cur = sizeof(float)*mxDn*node->n_tasks; // TODO: this can become (n_tasks-1) + cur += sizeof(float)*mxDn*node->n_tasks; // this is overestimated by x2 + } + + if (node->src1->type == GGML_TYPE_F16) { + cur = sizeof(float)*mxDn*node->n_tasks; // TODO: this can become (n_tasks-1) + cur += sizeof(float)*mxDn*node->n_tasks; // this is overestimated by x2 + } + work_size = MAX(work_size, cur); } break; case GGML_OP_MAP_UNARY: diff --git a/ggml.h b/ggml.h index ba60588d6..5dc80e74b 100644 --- a/ggml.h +++ b/ggml.h @@ -318,6 +318,7 @@ extern "C" { GGML_OP_FLASH_ATTN, GGML_OP_FLASH_FF, + GGML_OP_FLASH_ATTN_BACK, GGML_OP_MAP_UNARY, GGML_OP_MAP_BINARY, @@ -952,6 +953,14 @@ extern "C" { struct ggml_tensor * v, bool masked); + GGML_API struct ggml_tensor * ggml_flash_attn_back( + struct ggml_context * ctx, + struct ggml_tensor * q, + struct ggml_tensor * k, + struct ggml_tensor * v, + struct ggml_tensor * d, + bool masked); + GGML_API struct ggml_tensor * ggml_flash_ff( struct ggml_context * ctx, struct ggml_tensor * a,