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#include <linux/perf_event.h>
#include <sys/syscall.h>
#include <sys/mman.h>
#include <sys/user.h>
#include <unistd.h>
#include <string.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <err.h>
int main(int argc, char **argv) {
if (argc != 2) {
fprintf(stderr, "Usage: %s CPU\n", argv[0]);
return 1;
}
int cpu = atoi(argv[1]);
struct perf_event_attr attr;
memset(&attr, 0, sizeof(attr));
attr.type = PERF_TYPE_HARDWARE;
attr.size = sizeof(struct perf_event_attr);
attr.freq = 1;
attr.sample_freq = 10000;
attr.config = PERF_COUNT_HW_CPU_CYCLES;
int fd = syscall(
SYS_perf_event_open,
&attr, /* attributes */
-1, /* monitor all tasks */
cpu, /* selected CPU */
-1, /* group leader */
PERF_FLAG_FD_CLOEXEC /* flags */
);
if (fd == -1)
err(1, "perf_event_open");
pause();
/*
void *addr = mmap(NULL, PAGE_SIZE, PROT_READ, MAP_SHARED, fd, 0);
if (addr == MAP_FAILED) {
err(1, "mmap");
}
*/
return 0;
}
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