builtin-kallsyms.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * builtin-kallsyms.c
 4 *
 5 * Builtin command: Look for a symbol in the running kernel and its modules
 6 *
 7 * Copyright (C) 2017, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
 8 */
 9#include <inttypes.h>
10#include "builtin.h"
11#include <linux/compiler.h>
12#include <subcmd/parse-options.h>
13#include "debug.h"
14#include "dso.h"
15#include "env.h"
16#include "machine.h"
17#include "map.h"
18#include "symbol.h"
19
20static int __cmd_kallsyms(int argc, const char **argv)
21{
22	int i, err;
23	struct perf_env host_env;
24	struct machine *machine = NULL;
25
26
27	perf_env__init(&host_env);
28	err = perf_env__set_cmdline(&host_env, argc, argv);
29	if (err)
30		goto out;
31
32	machine = machine__new_kallsyms(&host_env);
33	if (machine == NULL) {
34		pr_err("Couldn't read /proc/kallsyms\n");
35		err = -1;
36		goto out;
37	}
38
39	for (i = 0; i < argc; ++i) {
40		struct map *map;
41		const struct dso *dso;
42		struct symbol *symbol = machine__find_kernel_symbol_by_name(machine, argv[i], &map);
43
44		if (symbol == NULL) {
45			printf("%s: not found\n", argv[i]);
46			continue;
47		}
48
49		dso = map__dso(map);
50		printf("%s: %s %s %#" PRIx64 "-%#" PRIx64 " (%#" PRIx64 "-%#" PRIx64")\n",
51			symbol->name, dso__short_name(dso), dso__long_name(dso),
52			map__unmap_ip(map, symbol->start), map__unmap_ip(map, symbol->end),
53			symbol->start, symbol->end);
54	}
55out:
56	machine__delete(machine);
57	perf_env__exit(&host_env);
58	return err;
59}
60
61int cmd_kallsyms(int argc, const char **argv)
62{
63	const struct option options[] = {
64	OPT_INCR('v', "verbose", &verbose, "be more verbose (show counter open errors, etc)"),
65	OPT_END()
66	};
67	const char * const kallsyms_usage[] = {
68		"perf kallsyms [<options>] symbol_name",
69		NULL
70	};
71
72	argc = parse_options(argc, argv, options, kallsyms_usage, 0);
73	if (argc < 1)
74		usage_with_options(kallsyms_usage, options);
75
76	symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
77	if (symbol__init(NULL) < 0)
78		return -1;
79
80	return __cmd_kallsyms(argc, argv);
81}