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/* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*/
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <fcntl.h>
#include <poll.h>
#include <linux/perf_event.h>
#include <linux/bpf.h>
#include <errno.h>
#include <assert.h>
#include <sys/syscall.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <time.h>
#include <signal.h>
#include "libbpf.h"
#include "bpf_load.h"
#include "perf-sys.h"
#include "trace_helpers.h"
static int pmu_fd;
static __u64 time_get_ns(void)
{
struct timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return ts.tv_sec * 1000000000ull + ts.tv_nsec;
}
static __u64 start_time;
#define MAX_CNT 100000ll
static int print_bpf_output(void *data, int size)
{
static __u64 cnt;
struct {
__u64 pid;
__u64 cookie;
} *e = data;
if (e->cookie != 0x12345678) {
printf("BUG pid %llx cookie %llx sized %d\n",
e->pid, e->cookie, size);
return LIBBPF_PERF_EVENT_ERROR;
}
cnt++;
if (cnt == MAX_CNT) {
printf("recv %lld events per sec\n",
MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
return LIBBPF_PERF_EVENT_DONE;
}
return LIBBPF_PERF_EVENT_CONT;
}
static void test_bpf_perf_event(void)
{
struct perf_event_attr attr = {
.sample_type = PERF_SAMPLE_RAW,
.type = PERF_TYPE_SOFTWARE,
.config = PERF_COUNT_SW_BPF_OUTPUT,
};
int key = 0;
pmu_fd = sys_perf_event_open(&attr, -1/*pid*/, 0/*cpu*/, -1/*group_fd*/, 0);
assert(pmu_fd >= 0);
assert(bpf_map_update_elem(map_fd[0], &key, &pmu_fd, BPF_ANY) == 0);
ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0);
}
int main(int argc, char **argv)
{
char filename[256];
FILE *f;
int ret;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
if (load_bpf_file(filename)) {
printf("%s", bpf_log_buf);
return 1;
}
test_bpf_perf_event();
if (perf_event_mmap(pmu_fd) < 0)
return 1;
f = popen("taskset 1 dd if=/dev/zero of=/dev/null", "r");
(void) f;
start_time = time_get_ns();
ret = perf_event_poller(pmu_fd, print_bpf_output);
kill(0, SIGINT);
return ret;
}
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