Linux：查看线程运行于哪个CPU核心上

Linux：查看线程运行于哪个CPU核心上
线程是最小的执行调度单元，线程执行于某个CPU核心之上，或者说某个CPU核心执行此线程。

如何查看某线程运行于哪个CPU核心上呢？

ps -eLF 查找 PSR 字段值

ps -eLF
UID         PID   PPID    LWP  C NLWP    SZ   RSS PSR STIME TTY          TIME CMD
root          1      0      1  0    1  4836  1548   2 Feb25 ?        00:00:02 /sbin/init
root          2      0      2  0    1     0     0   2 Feb25 ?        00:00:00 [kthreadd]
root          3      2      3  0    1     0     0   0 Feb25 ?        00:00:00 [migration/0]
……

#define _GNU_SOURCE

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <pthread.h>

void *start_routine(void *arg) {
   
  const char *msg = "thread: i am thread";
  while (1) {
   
    write(1, msg, strlen(msg));
    sleep(1);
  }
}

int main(