mirror of
https://github.com/torvalds/linux.git
synced 2024-12-22 10:56:40 +00:00
28dbf861de
There is no functionality change in this patch. The common-purpose trace functions, including perf_event polling and ksym lookup, are moved from trace_output_user.c and bpf_load.c to selftests/bpf/trace_helpers.c so that these function can be reused later in selftests. Acked-by: Alexei Starovoitov <ast@fb.com> Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
123 lines
2.5 KiB
C
123 lines
2.5 KiB
C
/* Copyright (c) 2016 Facebook
|
|
*
|
|
* 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 <signal.h>
|
|
#include <linux/bpf.h>
|
|
#include <string.h>
|
|
#include <linux/perf_event.h>
|
|
#include <errno.h>
|
|
#include <assert.h>
|
|
#include <stdbool.h>
|
|
#include <sys/resource.h>
|
|
#include "libbpf.h"
|
|
#include "bpf_load.h"
|
|
#include "trace_helpers.h"
|
|
|
|
#define PRINT_RAW_ADDR 0
|
|
|
|
static void print_ksym(__u64 addr)
|
|
{
|
|
struct ksym *sym;
|
|
|
|
if (!addr)
|
|
return;
|
|
sym = ksym_search(addr);
|
|
if (PRINT_RAW_ADDR)
|
|
printf("%s/%llx;", sym->name, addr);
|
|
else
|
|
printf("%s;", sym->name);
|
|
}
|
|
|
|
#define TASK_COMM_LEN 16
|
|
|
|
struct key_t {
|
|
char waker[TASK_COMM_LEN];
|
|
char target[TASK_COMM_LEN];
|
|
__u32 wret;
|
|
__u32 tret;
|
|
};
|
|
|
|
static void print_stack(struct key_t *key, __u64 count)
|
|
{
|
|
__u64 ip[PERF_MAX_STACK_DEPTH] = {};
|
|
static bool warned;
|
|
int i;
|
|
|
|
printf("%s;", key->target);
|
|
if (bpf_map_lookup_elem(map_fd[3], &key->tret, ip) != 0) {
|
|
printf("---;");
|
|
} else {
|
|
for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--)
|
|
print_ksym(ip[i]);
|
|
}
|
|
printf("-;");
|
|
if (bpf_map_lookup_elem(map_fd[3], &key->wret, ip) != 0) {
|
|
printf("---;");
|
|
} else {
|
|
for (i = 0; i < PERF_MAX_STACK_DEPTH; i++)
|
|
print_ksym(ip[i]);
|
|
}
|
|
printf(";%s %lld\n", key->waker, count);
|
|
|
|
if ((key->tret == -EEXIST || key->wret == -EEXIST) && !warned) {
|
|
printf("stackmap collisions seen. Consider increasing size\n");
|
|
warned = true;
|
|
} else if (((int)(key->tret) < 0 || (int)(key->wret) < 0)) {
|
|
printf("err stackid %d %d\n", key->tret, key->wret);
|
|
}
|
|
}
|
|
|
|
static void print_stacks(int fd)
|
|
{
|
|
struct key_t key = {}, next_key;
|
|
__u64 value;
|
|
|
|
while (bpf_map_get_next_key(fd, &key, &next_key) == 0) {
|
|
bpf_map_lookup_elem(fd, &next_key, &value);
|
|
print_stack(&next_key, value);
|
|
key = next_key;
|
|
}
|
|
}
|
|
|
|
static void int_exit(int sig)
|
|
{
|
|
print_stacks(map_fd[0]);
|
|
exit(0);
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
|
|
char filename[256];
|
|
int delay = 1;
|
|
|
|
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
|
|
setrlimit(RLIMIT_MEMLOCK, &r);
|
|
|
|
signal(SIGINT, int_exit);
|
|
signal(SIGTERM, int_exit);
|
|
|
|
if (load_kallsyms()) {
|
|
printf("failed to process /proc/kallsyms\n");
|
|
return 2;
|
|
}
|
|
|
|
if (load_bpf_file(filename)) {
|
|
printf("%s", bpf_log_buf);
|
|
return 1;
|
|
}
|
|
|
|
if (argc > 1)
|
|
delay = atoi(argv[1]);
|
|
sleep(delay);
|
|
print_stacks(map_fd[0]);
|
|
|
|
return 0;
|
|
}
|