linux/samples/bpf/tracex6_user.c

73 lines
1.4 KiB
C

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <fcntl.h>
#include <poll.h>
#include <sys/ioctl.h>
#include <linux/perf_event.h>
#include <linux/bpf.h>
#include "libbpf.h"
#include "bpf_load.h"
#define SAMPLE_PERIOD 0x7fffffffffffffffULL
static void test_bpf_perf_event(void)
{
int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
int *pmu_fd = malloc(nr_cpus * sizeof(int));
int status, i;
struct perf_event_attr attr_insn_pmu = {
.freq = 0,
.sample_period = SAMPLE_PERIOD,
.inherit = 0,
.type = PERF_TYPE_HARDWARE,
.read_format = 0,
.sample_type = 0,
.config = 0,/* PMU: cycles */
};
for (i = 0; i < nr_cpus; i++) {
pmu_fd[i] = perf_event_open(&attr_insn_pmu, -1/*pid*/, i/*cpu*/, -1/*group_fd*/, 0);
if (pmu_fd[i] < 0) {
printf("event syscall failed\n");
goto exit;
}
bpf_update_elem(map_fd[0], &i, &pmu_fd[i], BPF_ANY);
ioctl(pmu_fd[i], PERF_EVENT_IOC_ENABLE, 0);
}
status = system("ls > /dev/null");
if (status)
goto exit;
status = system("sleep 2");
if (status)
goto exit;
exit:
for (i = 0; i < nr_cpus; i++)
close(pmu_fd[i]);
close(map_fd[0]);
free(pmu_fd);
}
int main(int argc, char **argv)
{
char filename[256];
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();
read_trace_pipe();
return 0;
}