dnsdist: Add support for pinning backend threads to specific CPUs

diff --git a/pdns/dnsdist-lua.cc b/pdns/dnsdist-lua.cc
index cd22d401e270e0530dcb42d4d8a1a75d03c27cb7..bb706b8cb5d60b1bc4891fdc963f774dceb3db36 100644 (file)
--- a/pdns/dnsdist-lua.cc
+++ b/pdns/dnsdist-lua.cc
@@ -275,6 +275,7 @@ vector<std::function<void(void)>> setupLua(bool client, const std::string& confi
                        }
                        ComboAddress sourceAddr;
                        unsigned int sourceItf = 0;
+                        std::set<int> cpus;
                        if(auto addressStr = boost::get<string>(&pvars)) {
                          std::shared_ptr<DownstreamState> ret;
                          try {
@@ -404,8 +405,8 @@ vector<std::function<void(void)>> setupLua(bool client, const std::string& confi
                          if(auto* pool = boost::get<string>(&vars["pool"]))
                            ret->pools.insert(*pool);
                          else {
-                           auto* pools = boost::get<vector<pair<int, string> > >(&vars["pool"]);
-                           for(auto& p : *pools)
+                           auto pools = boost::get<vector<pair<int, string> > >(vars["pool"]);
+                           for(auto& p : pools)
                              ret->pools.insert(p.second);
                          }
                          for(const auto& poolName: ret->pools) {
@@ -480,14 +481,26 @@ vector<std::function<void(void)>> setupLua(bool client, const std::string& confi
                          ret->maxCheckFailures=std::stoi(boost::get<string>(vars["maxCheckFailures"]));
                        }
 
+                        if(vars.count("cpus")) {
+                          for (const auto cpu : boost::get<vector<pair<int,string>>>(vars["cpus"])) {
+                            cpus.insert(std::stoi(cpu.second));
+                          }
+                       }
+
                        if (ret->connected) {
                          if(g_launchWork) {
-                           g_launchWork->push_back([ret]() {
+                           g_launchWork->push_back([ret,cpus]() {
                              ret->tid = thread(responderThread, ret);
+                              if (!cpus.empty()) {
+                                mapThreadToCPUList(ret->tid.native_handle(), cpus);
+                              }
                            });
                          }
                          else {
                            ret->tid = thread(responderThread, ret);
+                            if (!cpus.empty()) {
+                              mapThreadToCPUList(ret->tid.native_handle(), cpus);
+                            }
                          }
                        }