我有4个线程,并且尝试将线程1设置为在CPU 1上运行,线程2在CPU 2上运行,等等。但是,当我在下面运行代码时,亲和力掩码返回正确的值,但是当我执行sched_getcpu()在线程上,它们都返回它们正在CPU 4上运行。
有人知道我的问题在这里吗?
提前致谢!
#define _GNU_SOURCE #include <stdio.h> #include <pthread.h> #include <stdlib.h> #include <sched.h> #include <errno.h> void *pthread_Message(char *message) { printf("%s is running on CPU %d\n", message, sched_getcpu()); } int main() { pthread_t thread1, thread2, thread3, thread4; pthread_t threadArray[4]; cpu_set_t cpu1, cpu2, cpu3, cpu4; char *thread1Msg = "Thread 1"; char *thread2Msg = "Thread 2"; char *thread3Msg = "Thread 3"; char *thread4Msg = "Thread 4"; int thread1Create, thread2Create, thread3Create, thread4Create, i, temp; CPU_ZERO(&cpu1); CPU_SET(1, &cpu1); temp = pthread_setaffinity_np(thread1, sizeof(cpu_set_t), &cpu1); printf("Set returned by pthread_getaffinity_np() contained:\n"); for (i = 0; i < CPU_SETSIZE; i++) if (CPU_ISSET(i, &cpu1)) printf("CPU1: CPU %d\n", i); CPU_ZERO(&cpu2); CPU_SET(2, &cpu2); temp = pthread_setaffinity_np(thread2, sizeof(cpu_set_t), &cpu2); for (i = 0; i < CPU_SETSIZE; i++) if (CPU_ISSET(i, &cpu2)) printf("CPU2: CPU %d\n", i); CPU_ZERO(&cpu3); CPU_SET(3, &cpu3); temp = pthread_setaffinity_np(thread3, sizeof(cpu_set_t), &cpu3); for (i = 0; i < CPU_SETSIZE; i++) if (CPU_ISSET(i, &cpu3)) printf("CPU3: CPU %d\n", i); CPU_ZERO(&cpu4); CPU_SET(4, &cpu4); temp = pthread_setaffinity_np(thread4, sizeof(cpu_set_t), &cpu4); for (i = 0; i < CPU_SETSIZE; i++) if (CPU_ISSET(i, &cpu4)) printf("CPU4: CPU %d\n", i); thread1Create = pthread_create(&thread1, NULL, (void *)pthread_Message, thread1Msg); thread2Create = pthread_create(&thread2, NULL, (void *)pthread_Message, thread2Msg); thread3Create = pthread_create(&thread3, NULL, (void *)pthread_Message, thread3Msg); thread4Create = pthread_create(&thread4, NULL, (void *)pthread_Message, thread4Msg); pthread_join(thread1, NULL); pthread_join(thread2, NULL); pthread_join(thread3, NULL); pthread_join(thread4, NULL); return 0; }
您正在尝试设置未初始化的线程的相似性。
编辑:好的,让我给您更多信息:
不要混合使用线程句柄(存储在pthread_t变量中的东西)和它们代表的内容(在某个地方运行的执行线程)。您试图做的是使用需要线程对象的API在启动之前设置线程的属性。碰巧pthread_create会创建对象并同时开始执行,因此尝试使用pthread_setaffinity_np不是正确的方法(如果要 更改 当前正在运行的线程的相似性,这将非常有用)。
pthread_setaffinity_np
但是… pthread_create具有一个属性参数(您正在向其传递NULL)。这将存储有关如何创建线程的信息。
pthread_create
亲和力是您可以通过该参数设置的属性之一。请参阅手册页文档pthread_attr_init,pthread_attr_setaffinity_np以了解其精确性
pthread_attr_init
pthread_attr_setaffinity_np