linux/samples/bpf/ibumad_user.c
Aditya Srivastava 4ce7d68beb samples: bpf: Ix kernel-doc syntax in file header
The opening comment mark '/**' is used for highlighting the beginning of
kernel-doc comments.
The header for samples/bpf/ibumad_kern.c follows this syntax, but
the content inside does not comply with kernel-doc.

This line was probably not meant for kernel-doc parsing, but is parsed
due to the presence of kernel-doc like comment syntax(i.e, '/**'), which
causes unexpected warnings from kernel-doc:
warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * ibumad BPF sample kernel side

Provide a simple fix by replacing this occurrence with general comment
format, i.e. '/*', to prevent kernel-doc from parsing it.

Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/bpf/20210523151408.22280-1-yashsri421@gmail.com
2021-05-24 21:06:02 -07:00

160 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
/*
* ibumad BPF sample user side
*
* 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.
*
* Copyright(c) 2018 Ira Weiny, Intel Corporation
*/
#include <linux/bpf.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <limits.h>
#include <sys/resource.h>
#include <getopt.h>
#include <net/if.h>
#include <bpf/bpf.h>
#include "bpf_util.h"
#include <bpf/libbpf.h>
static struct bpf_link *tp_links[3];
static struct bpf_object *obj;
static int map_fd[2];
static int tp_cnt;
static void dump_counts(int fd)
{
__u32 key;
__u64 value;
for (key = 0; key < 256; key++) {
if (bpf_map_lookup_elem(fd, &key, &value)) {
printf("failed to read key %u\n", key);
continue;
}
if (value)
printf("0x%02x : %llu\n", key, value);
}
}
static void dump_all_counts(void)
{
printf("Read 'Class : count'\n");
dump_counts(map_fd[0]);
printf("Write 'Class : count'\n");
dump_counts(map_fd[1]);
}
static void dump_exit(int sig)
{
dump_all_counts();
/* Detach tracepoints */
while (tp_cnt)
bpf_link__destroy(tp_links[--tp_cnt]);
bpf_object__close(obj);
exit(0);
}
static const struct option long_options[] = {
{"help", no_argument, NULL, 'h'},
{"delay", required_argument, NULL, 'd'},
};
static void usage(char *cmd)
{
printf("eBPF test program to count packets from various IP addresses\n"
"Usage: %s <options>\n"
" --help, -h this menu\n"
" --delay, -d <delay> wait <delay> sec between prints [1 - 1000000]\n"
, cmd
);
}
int main(int argc, char **argv)
{
struct bpf_program *prog;
unsigned long delay = 5;
char filename[256];
int longindex = 0;
int opt, err = -1;
while ((opt = getopt_long(argc, argv, "hd:rSw",
long_options, &longindex)) != -1) {
switch (opt) {
case 'd':
delay = strtoul(optarg, NULL, 0);
if (delay == ULONG_MAX || delay < 0 ||
delay > 1000000) {
fprintf(stderr, "ERROR: invalid delay : %s\n",
optarg);
usage(argv[0]);
return 1;
}
break;
default:
case 'h':
usage(argv[0]);
return 1;
}
}
/* Do one final dump when exiting */
signal(SIGINT, dump_exit);
signal(SIGTERM, dump_exit);
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
obj = bpf_object__open_file(filename, NULL);
if (libbpf_get_error(obj)) {
fprintf(stderr, "ERROR: opening BPF object file failed\n");
return err;
}
/* load BPF program */
if (bpf_object__load(obj)) {
fprintf(stderr, "ERROR: loading BPF object file failed\n");
goto cleanup;
}
map_fd[0] = bpf_object__find_map_fd_by_name(obj, "read_count");
map_fd[1] = bpf_object__find_map_fd_by_name(obj, "write_count");
if (map_fd[0] < 0 || map_fd[1] < 0) {
fprintf(stderr, "ERROR: finding a map in obj file failed\n");
goto cleanup;
}
bpf_object__for_each_program(prog, obj) {
tp_links[tp_cnt] = bpf_program__attach(prog);
if (libbpf_get_error(tp_links[tp_cnt])) {
fprintf(stderr, "ERROR: bpf_program__attach failed\n");
tp_links[tp_cnt] = NULL;
goto cleanup;
}
tp_cnt++;
}
while (1) {
sleep(delay);
dump_all_counts();
}
err = 0;
cleanup:
/* Detach tracepoints */
while (tp_cnt)
bpf_link__destroy(tp_links[--tp_cnt]);
bpf_object__close(obj);
return err;
}