1 // Copyright 2016 Google Inc. All rights reserved 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #include "affinity.h" 16 17 #include "flags.h" 18 #include "log.h" 19 20 #ifdef __linux__ 21 22 #include <sched.h> 23 24 void SetAffinityForSingleThread() { 25 cpu_set_t cs; 26 CPU_ZERO(&cs); 27 int n = g_flags.num_cpus / 2; 28 CPU_SET(n, &cs); 29 if (n > 1) 30 CPU_SET(n + 1, &cs); 31 if (sched_setaffinity(0, sizeof(cs), &cs) < 0) 32 WARN("sched_setaffinity: %s", strerror(errno)); 33 } 34 35 void SetAffinityForMultiThread() { 36 cpu_set_t cs; 37 CPU_ZERO(&cs); 38 for (int i = 0; i < g_flags.num_cpus; i++) { 39 CPU_SET(i, &cs); 40 } 41 if (sched_setaffinity(0, sizeof(cs), &cs) < 0) 42 WARN("sched_setaffinity: %s", strerror(errno)); 43 } 44 45 #else 46 47 void SetAffinityForSingleThread() {} 48 void SetAffinityForMultiThread() {} 49 50 #endif 51
