频繁设置CGroup触发linux内核bug导致CGroup running task不调度

#include <iostream> #include <sys/types.h> #include <signal.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <sys/stat.h> #include <pthread.h> #include <sys/time.h> #include <string>  using namespace std; std::string sub_cgroup_dir("/sys/fs/cgroup/cpu/test");  // common lib bool is_dir(const std::string& path) {     struct stat statbuf;     if (stat(path.c_str(), &statbuf) == 0 )     {         if (0 != S_ISDIR(statbuf.st_mode))         {             return true;         }     }     return false; }  bool write_file(const std::string& file_path, int num) {     FILE* fp = fopen(file_path.c_str(), "w");     if (fp = NULL)     {         return false;     }      std::string write_data = to_string(num);     fputs(write_data.c_str(), fp);     fclose(fp);     return true; }  // ms long get_ms_timestamp() {     timeval tv;     gettimeofday(&tv, NULL);     return (tv.tv_sec * 1000 + tv.tv_usec / 1000); }  // cgroup bool create_cgroup() {     if (is_dir(sub_cgroup_dir) == false)     {         if (mkdir(sub_cgroup_dir.c_str(), S_IRWXU | S_IRGRP) != 0)         {             cout << "mkdir cgroup dir fail" << endl;             return false;         }     }      int pid = getpid();     cout << "pid is " << pid << endl;     std::string procs_path = sub_cgroup_dir + "/cgroup.procs";     return write_file(procs_path, pid); }  bool set_period(int period) {     std::string period_path = sub_cgroup_dir + "/cpu.cfs_period_us";     return write_file(period_path, period); }  bool set_quota(int quota) {     std::string quota_path = sub_cgroup_dir + "/cpu.cfs_quota_us";     return write_file(quota_path, quota); }  // thread // param: ms interval void* thread_func(void* param) {     int i = 0;     int interval = (long)param;     long last = get_ms_timestamp();      while (true)     {         i++;         if (i % 1000 != 0)         {             continue;         }          long current = get_ms_timestamp();         if ((current - last) >= interval)         {             usleep(1000);             last = current;         }     }      pthread_exit(NULL); }   void test_thread()  {     const int k_thread_num = 10;     pthread_t pthreads[k_thread_num];      for (int i = 0; i < k_thread_num; i++)     {         if (pthread_create(&pthreads[i], NULL, thread_func, (void*)(i + 1)) != 0)         {             cout << "create thread fail" << endl;         }         else         {             cout << "create thread success,tid is " << pthreads[i] << endl;         }     } }  //argv[0] : period //argv[1] : quota int main(int argc,char* argv[]) {     if (argc <3)     {         cout << "usage : ./inactive timer $period $quota" << endl;         return -1;     }      int period = stoi(argv[1]);     int quota = stoi(argv[2]);     cout << "period is " << period << endl;     cout << "quota is " << quota << endl;      test_thread();     if (create_cgroup() == false)     {         cout << "create cgroup fail" << endl;         return -1;     }      int i =0;     while (true)     {         if (i > 20)         {             i = 0;         }          i++;         long current = get_ms_timestamp();         long last = current;         while ((current - last) < i)         {             usleep(1000);             current = get_ms_timestamp();         }                  set_period(period);         set_quota(quota);     }      return 0; }