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authorTor Aamodt <[email protected]>2020-07-04 16:26:52 -0700
committerGitHub <[email protected]>2020-07-04 16:26:52 -0700
commit673f8a9f0056b456871642f4d25be5c598fcba6e (patch)
treea9f379ae6ff144e8f3eccd3d510a36c2c0983edd /src/gpgpu-sim/local_interconnect.cc
parentc9cc4281bf84ad6cff77d20389b59d14a534ad6b (diff)
parent9d3caa1cb2c70a3be186d4704ecab0fe13277516 (diff)
Merge pull request #1 from gpgpu-sim/dev
Dev
Diffstat (limited to 'src/gpgpu-sim/local_interconnect.cc')
-rw-r--r--src/gpgpu-sim/local_interconnect.cc368
1 files changed, 368 insertions, 0 deletions
diff --git a/src/gpgpu-sim/local_interconnect.cc b/src/gpgpu-sim/local_interconnect.cc
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+// Copyright (c) 2019, Mahmoud Khairy
+// Purdue University
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// Redistributions of source code must retain the above copyright notice, this
+// list of conditions and the following disclaimer.
+// Redistributions in binary form must reproduce the above copyright notice,
+// this list of conditions and the following disclaimer in the documentation
+// and/or other materials provided with the distribution. Neither the name of
+// The University of British Columbia nor the names of its contributors may be
+// used to endorse or promote products derived from this software without
+// specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+
+#include <algorithm>
+#include <cmath>
+#include <fstream>
+#include <iomanip>
+#include <iostream>
+#include <sstream>
+#include <utility>
+
+#include "local_interconnect.h"
+#include "mem_fetch.h"
+
+xbar_router::xbar_router(unsigned router_id, enum Interconnect_type m_type,
+ unsigned n_shader, unsigned n_mem,
+ unsigned m_in_buffer_limit,
+ unsigned m_out_buffer_limit,
+ enum Arbiteration_type m_arbit_type) {
+ m_id = router_id;
+ router_type = m_type;
+ _n_mem = n_mem;
+ _n_shader = n_shader;
+ total_nodes = n_shader + n_mem;
+ in_buffers.resize(total_nodes);
+ out_buffers.resize(total_nodes);
+ next_node.resize(total_nodes, 0);
+ in_buffer_limit = m_in_buffer_limit;
+ out_buffer_limit = m_out_buffer_limit;
+ arbit_type = m_arbit_type;
+ next_node_id = 0;
+ if (m_type == REQ_NET) {
+ active_in_buffers = n_shader;
+ active_out_buffers = n_mem;
+ } else if (m_type == REPLY_NET) {
+ active_in_buffers = n_mem;
+ active_out_buffers = n_shader;
+ }
+
+ cycles = 0;
+ conflicts = 0;
+ out_buffer_full = 0;
+ in_buffer_full = 0;
+ out_buffer_util = 0;
+ in_buffer_util = 0;
+ packets_num = 0;
+}
+
+xbar_router::~xbar_router() {}
+
+void xbar_router::Push(unsigned input_deviceID, unsigned output_deviceID,
+ void* data, unsigned int size) {
+ assert(input_deviceID < total_nodes);
+ in_buffers[input_deviceID].push(Packet(data, output_deviceID));
+ packets_num++;
+}
+
+void* xbar_router::Pop(unsigned ouput_deviceID) {
+ assert(ouput_deviceID < total_nodes);
+ void* data = NULL;
+
+ if (!out_buffers[ouput_deviceID].empty()) {
+ data = out_buffers[ouput_deviceID].front().data;
+ out_buffers[ouput_deviceID].pop();
+ }
+
+ return data;
+}
+
+bool xbar_router::Has_Buffer_In(unsigned input_deviceID, unsigned size,
+ bool update_counter) {
+ assert(input_deviceID < total_nodes);
+
+ bool has_buffer =
+ (in_buffers[input_deviceID].size() + size <= in_buffer_limit);
+ if (update_counter && !has_buffer) in_buffer_full++;
+
+ return has_buffer;
+}
+
+bool xbar_router::Has_Buffer_Out(unsigned output_deviceID, unsigned size) {
+ return (out_buffers[output_deviceID].size() + size <= out_buffer_limit);
+}
+
+void xbar_router::Advance() {
+ if (arbit_type == NAIVE_RR)
+ RR_Advance();
+ else if (arbit_type == iSLIP)
+ iSLIP_Advance();
+ else
+ assert(0);
+}
+
+void xbar_router::RR_Advance() {
+ cycles++;
+
+ vector<bool> issued(total_nodes, false);
+
+ for (unsigned i = 0; i < total_nodes; ++i) {
+ unsigned node_id = (i + next_node_id) % total_nodes;
+
+ if (!in_buffers[node_id].empty()) {
+ Packet _packet = in_buffers[node_id].front();
+ // ensure that the outbuffer has space and not issued before in this cycle
+ if (Has_Buffer_Out(_packet.output_deviceID, 1)) {
+ if (!issued[_packet.output_deviceID]) {
+ out_buffers[_packet.output_deviceID].push(_packet);
+ in_buffers[node_id].pop();
+ issued[_packet.output_deviceID] = true;
+ } else
+ conflicts++;
+ } else {
+ out_buffer_full++;
+
+ if (issued[_packet.output_deviceID]) conflicts++;
+ }
+ }
+ }
+
+ next_node_id = (++next_node_id % total_nodes);
+
+ // collect some stats about buffer util
+ for (unsigned i = 0; i < total_nodes; ++i) {
+ in_buffer_util += in_buffers[i].size();
+ out_buffer_util += out_buffers[i].size();
+ }
+}
+
+// iSLIP algorithm
+// McKeown, Nick. "The iSLIP scheduling algorithm for input-queued switches."
+// IEEE/ACM transactions on networking 2 (1999): 188-201.
+// https://www.cs.rutgers.edu/~sn624/552-F18/papers/islip.pdf
+void xbar_router::iSLIP_Advance() {
+ cycles++;
+
+ vector<unsigned> node_tmp;
+
+ // calcaulte how many conflicts are there for stats
+ for (unsigned i = 0; i < total_nodes; ++i) {
+ if (!in_buffers[i].empty()) {
+ Packet _packet_tmp = in_buffers[i].front();
+ if (!node_tmp.empty()) {
+ if (std::find(node_tmp.begin(), node_tmp.end(),
+ _packet_tmp.output_deviceID) != node_tmp.end()) {
+ conflicts++;
+ } else
+ node_tmp.push_back(_packet_tmp.output_deviceID);
+ } else {
+ node_tmp.push_back(_packet_tmp.output_deviceID);
+ }
+ }
+ }
+
+ // do iSLIP
+ for (unsigned i = 0; i < total_nodes; ++i) {
+ if (Has_Buffer_Out(i, 1)) {
+ for (unsigned j = 0; j < total_nodes; ++j) {
+ unsigned node_id = (j + next_node[i]) % total_nodes;
+
+ if (!in_buffers[node_id].empty()) {
+ Packet _packet = in_buffers[node_id].front();
+ if (_packet.output_deviceID == i) {
+ out_buffers[_packet.output_deviceID].push(_packet);
+ in_buffers[node_id].pop();
+ next_node[i] = (++node_id % total_nodes);
+ break;
+ }
+ }
+ }
+ } else
+ out_buffer_full++;
+ }
+
+ // collect some stats about buffer util
+ for (unsigned i = 0; i < total_nodes; ++i) {
+ in_buffer_util += in_buffers[i].size();
+ out_buffer_util += out_buffers[i].size();
+ }
+}
+
+bool xbar_router::Busy() const {
+ for (unsigned i = 0; i < total_nodes; ++i) {
+ if (!in_buffers[i].empty()) return true;
+
+ if (!out_buffers[i].empty()) return true;
+ }
+ return false;
+}
+
+////////////////////////////////////////////////////
+/////////////LocalInterconnect/////////////////////
+
+// assume all the packets are one flit
+#define LOCAL_INCT_FLIT_SIZE 40
+
+LocalInterconnect* LocalInterconnect::New(
+ const struct inct_config& m_localinct_config) {
+ LocalInterconnect* icnt_interface = new LocalInterconnect(m_localinct_config);
+
+ return icnt_interface;
+}
+
+LocalInterconnect::LocalInterconnect(
+ const struct inct_config& m_localinct_config)
+ : m_inct_config(m_localinct_config) {
+ n_shader = 0;
+ n_mem = 0;
+ n_subnets = m_localinct_config.subnets;
+}
+
+LocalInterconnect::~LocalInterconnect() {
+ for (unsigned i = 0; i < m_inct_config.subnets; ++i) {
+ delete net[i];
+ }
+}
+
+void LocalInterconnect::CreateInterconnect(unsigned m_n_shader,
+ unsigned m_n_mem) {
+ n_shader = m_n_shader;
+ n_mem = m_n_mem;
+
+ net.resize(n_subnets);
+ for (unsigned i = 0; i < n_subnets; ++i) {
+ net[i] = new xbar_router(i, static_cast<Interconnect_type>(i), m_n_shader,
+ m_n_mem, m_inct_config.in_buffer_limit,
+ m_inct_config.out_buffer_limit,
+ m_inct_config.arbiter_algo);
+ }
+}
+
+void LocalInterconnect::Init() {
+ // empty
+ // there is nothing to do
+}
+
+void LocalInterconnect::Push(unsigned input_deviceID, unsigned output_deviceID,
+ void* data, unsigned int size) {
+ unsigned subnet;
+ if (n_subnets == 1) {
+ subnet = 0;
+ } else {
+ if (input_deviceID < n_shader) {
+ subnet = 0;
+ } else {
+ subnet = 1;
+ }
+ }
+
+ // it should have free buffer
+ // assume all the packets have size of one
+ // no flits are implemented
+ assert(net[subnet]->Has_Buffer_In(input_deviceID, 1));
+
+ net[subnet]->Push(input_deviceID, output_deviceID, data, size);
+}
+
+void* LocalInterconnect::Pop(unsigned ouput_deviceID) {
+ // 0-_n_shader-1 indicates reply(network 1), otherwise request(network 0)
+ int subnet = 0;
+ if (ouput_deviceID < n_shader) subnet = 1;
+
+ return net[subnet]->Pop(ouput_deviceID);
+}
+
+void LocalInterconnect::Advance() {
+ for (unsigned i = 0; i < n_subnets; ++i) {
+ net[i]->Advance();
+ }
+}
+
+bool LocalInterconnect::Busy() const {
+ for (unsigned i = 0; i < n_subnets; ++i) {
+ if (net[i]->Busy()) return true;
+ }
+ return false;
+}
+
+bool LocalInterconnect::HasBuffer(unsigned deviceID, unsigned int size) const {
+ bool has_buffer = false;
+
+ if ((n_subnets > 1) && deviceID >= n_shader) // deviceID is memory node
+ has_buffer = net[REPLY_NET]->Has_Buffer_In(deviceID, 1, true);
+ else
+ has_buffer = net[REQ_NET]->Has_Buffer_In(deviceID, 1, true);
+
+ return has_buffer;
+}
+
+void LocalInterconnect::DisplayStats() const {
+ cout << "Req_Network_injected_packets_num = " << net[REQ_NET]->packets_num
+ << endl;
+ cout << "Req_Network_cycles = " << net[REQ_NET]->cycles << endl;
+ cout << "Req_Network_injected_packets_per_cycle = "
+ << (float)(net[REQ_NET]->packets_num) / (net[REQ_NET]->cycles) << endl;
+ cout << "Req_Network_conflicts_per_cycle = "
+ << (float)(net[REQ_NET]->conflicts) / (net[REQ_NET]->cycles) << endl;
+ cout << "Req_Network_in_buffer_full_per_cycle = "
+ << (float)(net[REQ_NET]->in_buffer_full) / (net[REQ_NET]->cycles)
+ << endl;
+ cout << "Req_Network_in_buffer_avg_util = "
+ << ((float)(net[REQ_NET]->in_buffer_util) / (net[REQ_NET]->cycles) /
+ net[REQ_NET]->active_in_buffers)
+ << endl;
+ cout << "Req_Network_out_buffer_full_per_cycle = "
+ << (float)(net[REQ_NET]->out_buffer_full) / (net[REQ_NET]->cycles)
+ << endl;
+ cout << "Req_Network_out_buffer_avg_util = "
+ << ((float)(net[REQ_NET]->out_buffer_util) / (net[REQ_NET]->cycles) /
+ net[REQ_NET]->active_out_buffers)
+ << endl;
+
+ cout << endl;
+ cout << "Reply_Network_injected_packets_num = " << net[REPLY_NET]->packets_num
+ << endl;
+ cout << "Reply_Network_cycles = " << net[REPLY_NET]->cycles << endl;
+ cout << "Reply_Network_injected_packets_per_cycle = "
+ << (float)(net[REPLY_NET]->packets_num) / (net[REPLY_NET]->cycles)
+ << endl;
+ cout << "Reply_Network_conflicts_per_cycle = "
+ << (float)(net[REPLY_NET]->conflicts) / (net[REPLY_NET]->cycles) << endl;
+ cout << "Reply_Network_in_buffer_full_per_cycle = "
+ << (float)(net[REPLY_NET]->in_buffer_full) / (net[REPLY_NET]->cycles)
+ << endl;
+ cout << "Reply_Network_in_buffer_avg_util = "
+ << ((float)(net[REPLY_NET]->in_buffer_util) / (net[REPLY_NET]->cycles) /
+ net[REPLY_NET]->active_in_buffers)
+ << endl;
+ cout << "Reply_Network_out_buffer_full_per_cycle = "
+ << (float)(net[REPLY_NET]->out_buffer_full) / (net[REPLY_NET]->cycles)
+ << endl;
+ cout << "Reply_Network_out_buffer_avg_util= "
+ << ((float)(net[REPLY_NET]->out_buffer_util) / (net[REPLY_NET]->cycles) /
+ net[REPLY_NET]->active_out_buffers)
+ << endl;
+}
+
+void LocalInterconnect::DisplayOverallStats() const {}
+
+unsigned LocalInterconnect::GetFlitSize() const { return LOCAL_INCT_FLIT_SIZE; }
+
+void LocalInterconnect::DisplayState(FILE* fp) const {
+ fprintf(fp, "GPGPU-Sim uArch: ICNT:Display State: Under implementation\n");
+}