diff --git a/paddle/fluid/framework/details/multi_devices_graph_builder.cc b/paddle/fluid/framework/details/multi_devices_graph_builder.cc index 4d76dbf7f6ffcf6c82ebf7defd9334bbe64a451c..882d438934920f6c3c51f73b41d5fe30b61043e7 100644 --- a/paddle/fluid/framework/details/multi_devices_graph_builder.cc +++ b/paddle/fluid/framework/details/multi_devices_graph_builder.cc @@ -89,101 +89,25 @@ std::unique_ptr MultiDevSSAGraphBuilder::Build( bool is_forwarding = true; for (auto *op : program.Block(0).AllOps()) { - bool change_forward = false; - if (!is_forwarding) { - // FIXME(yy): Do not hard code like this - if (op->OutputArgumentNames().size() == 1 && - op->OutputArgumentNames()[0] == GradVarName(loss_var_name_)) { - continue; // Drop fill 1. for backward coeff; - } - } - - // append send op if program is distributed trainer main program. - // always use the first device - if (!is_forwarding && op->Type() == "send") { - auto &p = places_[0]; - auto *s = local_scopes_[0]; - // FIXME(wuyi): send op always copy from GPU 0 - result.ops_.emplace_back(new SendOpHandle(*op, s, p)); - // Create inputs for output on original place and no ssa output - // is created for send op. - CreateOpHandleIOs(&result, *op, p, 0); - continue; - } - - for (size_t i = 0; i < places_.size(); ++i) { - auto &p = places_[i]; - auto *s = local_scopes_[i]; - - result.ops_.emplace_back(new ComputationOpHandle(*op, s, p)); - auto *op_handle = result.ops_.back().get(); - CreateOpHandleIOs(&result, *op, p, i); - - auto var_names = op->OutputArgumentNames(); - - if (is_forwarding) { - if (var_names.size() == 1 && var_names[0] == loss_var_name_) { -// Insert ScaleCost OpHandle -#ifdef PADDLE_WITH_CUDA - auto *communication_dev_ctx = nccl_ctxs_->DevCtx(p); -#else - auto *communication_dev_ctx = - platform::DeviceContextPool::Instance().Get(platform::CPUPlace()); -#endif - - op_handle = new ScaleLossGradOpHandle(local_scopes_.size(), s, p, - communication_dev_ctx); - result.ops_.emplace_back(op_handle); - - // FIXME: Currently ScaleLossGradOp only use device_count as scale - // factor. So it does not depend on any other operators. - // VarHandle *loss = GetVarHandle(loss_var_name, place); - // loss->pending_ops_.emplace_back(op_handle); - // op_handle->inputs_.emplace_back(loss); - - CreateOpOutput(&result, op_handle, GradVarName(loss_var_name_), p, i); - change_forward = true; - } - } - } - - if (change_forward) { + if (op->Type() == "send") { + // append send op if program is distributed trainer main program. + // always use the first device + CreateSendOp(&result, *op); + } else if (IsScaleLossOp(*op)) { + CreateScaleLossGradOp(&result); is_forwarding = false; - } - - if (!is_forwarding) { - auto var_names = op->OutputArgumentNames(); - // Currently, we assume that once gradient is generated, it can be - // broadcast, and each gradient is only broadcast once. But there are no - // other cases, for example, we need to adjust the gradient according to - // the input when we get the gradient, which is not considered at present. - for (auto &og : var_names) { - if (grad_names_.count(og) != 0 && - og_has_been_broadcast.count(og) == 0) { // is param grad - // Insert NCCL AllReduce Op - og_has_been_broadcast.insert(og); -#ifdef PADDLE_WITH_CUDA - result.ops_.emplace_back( - new NCCLAllReduceOpHandle(local_scopes_, places_, *nccl_ctxs_)); - auto *op_handle = result.ops_.back().get(); - - for (size_t i = 0; i < places_.size(); ++i) { - auto &p = places_[i]; - auto &vars = result.vars_[i][og]; - - if (vars.empty()) { // This device has no data. continue. - continue; - } - auto &prev_grad = vars[vars.size() - 1]; - op_handle->AddInput(prev_grad.get()); - - auto var = new VarHandle(vars.size() - 1, i, og, p); - vars.emplace_back(var); - op_handle->AddOutput(var); + } else { + CreateComputationalOps(&result, *op); + if (!is_forwarding) { + // Currently, we assume that once gradient is generated, it can be + // broadcast, and each gradient is only broadcast once. But there are no + // other cases, for example, we need to adjust the gradient according to + // the input when we get the gradient, which is not considered at + // present. + for (auto &og : op->OutputArgumentNames()) { + if (IsParameterGradientOnce(og, &og_has_been_broadcast)) { + InsertNCCLAllReduceOp(&result, og); } -#else - PADDLE_ENFORCE("Not implemented"); -#endif } } } @@ -207,7 +131,97 @@ std::unique_ptr MultiDevSSAGraphBuilder::Build( } return std::unique_ptr(graph); -} // namespace details +} + +void MultiDevSSAGraphBuilder::InsertNCCLAllReduceOp( + SSAGraph *result, const std::string &og) const { +#ifdef PADDLE_WITH_CUDA + result->ops_.emplace_back( + new NCCLAllReduceOpHandle(local_scopes_, places_, *nccl_ctxs_)); + auto *op_handle = result->ops_.back().get(); + + for (size_t i = 0; i < places_.size(); ++i) { + auto &p = places_[i]; + auto &vars = result->vars_[i][og]; + if (vars.empty()) { // This device has no data. continue. + continue; + } + auto &prev_grad = vars[vars.size() - 1]; + op_handle->AddInput(prev_grad.get()); + + auto var = new VarHandle(vars.size() - 1, i, og, p); + vars.emplace_back(var); + op_handle->AddOutput(var); + } +#else + PADDLE_ENFORCE("Not implemented"); +#endif +} + +bool MultiDevSSAGraphBuilder::IsParameterGradientOnce( + const std::string &og, + std::unordered_set *og_has_been_broadcast) const { + bool is_pg_once = + grad_names_.count(og) != 0 && og_has_been_broadcast->count(og) == 0; + if (is_pg_once) { + // Insert NCCL AllReduce Op + og_has_been_broadcast->insert(og); + } + return is_pg_once; +} + +void MultiDevSSAGraphBuilder::CreateScaleLossGradOp(SSAGraph *result) const { + for (size_t i = 0; i < places_.size(); ++i) { +// Insert ScaleCost OpHandle +#ifdef PADDLE_WITH_CUDA + auto *communication_dev_ctx = nccl_ctxs_->DevCtx(places_[i]); +#else + auto *communication_dev_ctx = + platform::DeviceContextPool::Instance().Get(platform::CPUPlace()); +#endif + + auto *op_handle = + new ScaleLossGradOpHandle(local_scopes_.size(), local_scopes_[i], + places_[i], communication_dev_ctx); + result->ops_.emplace_back(op_handle); + + // FIXME: Currently ScaleLossGradOp only use device_count as scale + // factor. So it does not depend on any other operators. + // VarHandle *loss = GetVarHandle(loss_var_name, place); + // loss->pending_ops_.emplace_back(op_handle); + // op_handle->inputs_.emplace_back(loss); + + CreateOpOutput(result, op_handle, GradVarName(loss_var_name_), places_[i], + i); + } +} + +void MultiDevSSAGraphBuilder::CreateComputationalOps(SSAGraph *result, + const OpDesc &op) const { + for (size_t scope_idx = 0; scope_idx < places_.size(); ++scope_idx) { + auto p = places_[scope_idx]; + auto s = local_scopes_[scope_idx]; + result->ops_.emplace_back(new ComputationOpHandle(op, s, p)); + CreateOpHandleIOs(result, op, p, scope_idx); + } +} + +void MultiDevSSAGraphBuilder::CreateSendOp(SSAGraph *result, + const OpDesc &op) const { + auto &p = places_[0]; + auto *s = local_scopes_[0]; + // FIXME(wuyi): send op always copy from GPU 0 + result->ops_.emplace_back(new SendOpHandle(op, s, p)); + // Create inputs for output on original place and no ssa output + // is created for send op. + CreateOpHandleIOs(result, op, p, 0); +} + +bool MultiDevSSAGraphBuilder::IsScaleLossOp(const OpDesc &op) const { + // FIXME(yy): Do not hard code like this + return op.OutputArgumentNames().size() == 1 && + op.OutputArgumentNames()[0] == GradVarName(loss_var_name_); +} } // namespace details } // namespace framework } // namespace paddle diff --git a/paddle/fluid/framework/details/multi_devices_graph_builder.h b/paddle/fluid/framework/details/multi_devices_graph_builder.h index f1518d75b421006db6311c3b0f602e47000ab381..b5ba2dbd3c00f23fabd993d7908664db38a31941 100644 --- a/paddle/fluid/framework/details/multi_devices_graph_builder.h +++ b/paddle/fluid/framework/details/multi_devices_graph_builder.h @@ -57,6 +57,20 @@ class MultiDevSSAGraphBuilder : public SSAGraphBuilder { #ifdef PADDLE_WITH_CUDA platform::NCCLContextMap *nccl_ctxs_; #endif + + bool IsScaleLossOp(const OpDesc &op) const; + + void CreateSendOp(SSAGraph *result, const OpDesc &op) const; + + void CreateComputationalOps(SSAGraph *result, const OpDesc &op) const; + + void CreateScaleLossGradOp(SSAGraph *result) const; + + bool IsParameterGradientOnce( + const std::string &og, + std::unordered_set *og_has_been_broadcast) const; + + void InsertNCCLAllReduceOp(SSAGraph *result, const std::string &og) const; }; } // namespace details } // namespace framework