mirror of
https://github.com/torvalds/linux.git
synced 2024-11-27 22:51:35 +00:00
5ed3ccbd5a
There are two improvements in this patch:
1. Fix the build warnings;
2. Add function read_trace_pipe() to print the result on
the screen;
Before this patch, we can get the result through /sys/kernel/de
bug/tracing/trace_pipe and get nothing on the screen.
By applying this patch, the result can be printed on the screen.
$ ./tracex6
...
tracex6-705 [003] d..1 131.428593: : CPU-3 19981414
sshd-683 [000] d..1 131.428727: : CPU-0 221682321
sshd-683 [000] d..1 131.428821: : CPU-0 221808766
sshd-683 [000] d..1 131.428950: : CPU-0 221982984
sshd-683 [000] d..1 131.429045: : CPU-0 222111851
tracex6-705 [003] d..1 131.429168: : CPU-3 20757551
sshd-683 [000] d..1 131.429170: : CPU-0 222281240
sshd-683 [000] d..1 131.429261: : CPU-0 222403340
sshd-683 [000] d..1 131.429378: : CPU-0 222561024
...
Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
73 lines
1.4 KiB
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;
|
|
}
|