4 * Builtin probe command: Set up probe events by C expression
6 * Written by Masami Hiramatsu <mhiramat@redhat.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 #include <sys/utsname.h>
25 #include <sys/types.h>
37 #include "util/util.h"
38 #include "util/strlist.h"
39 #include "util/event.h"
40 #include "util/debug.h"
41 #include "util/parse-options.h"
42 #include "util/parse-events.h" /* For debugfs_path */
43 #include "util/probe-finder.h"
44 #include "util/probe-event.h"
46 /* Default vmlinux search paths */
47 #define NR_SEARCH_PATH 4
48 const char *default_search_path[NR_SEARCH_PATH] = {
49 "/lib/modules/%s/build/vmlinux", /* Custom build kernel */
50 "/usr/lib/debug/lib/modules/%s/vmlinux", /* Red Hat debuginfo */
51 "/boot/vmlinux-debug-%s", /* Ubuntu */
52 "./vmlinux", /* CWD */
55 #define MAX_PATH_LEN 256
56 #define MAX_PROBES 128
58 /* Session management structure */
64 struct probe_point probes[MAX_PROBES];
65 struct strlist *dellist;
70 /* Parse an event definition. Note that any error must die. */
71 static void parse_probe_event(const char *str)
73 struct probe_point *pp = &session.probes[session.nr_probe];
75 pr_debug("probe-definition(%d): %s\n", session.nr_probe, str);
76 if (++session.nr_probe == MAX_PROBES)
77 die("Too many probes (> %d) are specified.", MAX_PROBES);
79 /* Parse perf-probe event into probe_point */
80 session.need_dwarf = parse_perf_probe_event(str, pp);
82 pr_debug("%d arguments\n", pp->nr_args);
85 static void parse_probe_event_argv(int argc, const char **argv)
90 /* Bind up rest arguments */
92 for (i = 0; i < argc; i++)
93 len += strlen(argv[i]) + 1;
94 buf = zalloc(len + 1);
96 die("Failed to allocate memory for binding arguments.");
98 for (i = 0; i < argc; i++)
99 len += sprintf(&buf[len], "%s ", argv[i]);
100 parse_probe_event(buf);
104 static int opt_add_probe_event(const struct option *opt __used,
105 const char *str, int unset __used)
108 parse_probe_event(str);
112 static int opt_del_probe_event(const struct option *opt __used,
113 const char *str, int unset __used)
116 if (!session.dellist)
117 session.dellist = strlist__new(true, NULL);
118 strlist__add(session.dellist, str);
124 static int open_default_vmlinux(void)
127 char fname[MAX_PATH_LEN];
132 pr_debug("uname() failed.\n");
135 session.release = uts.release;
136 for (i = 0; i < NR_SEARCH_PATH; i++) {
137 ret = snprintf(fname, MAX_PATH_LEN,
138 default_search_path[i], session.release);
139 if (ret >= MAX_PATH_LEN || ret < 0) {
140 pr_debug("Filename(%d,%s) is too long.\n", i,
145 pr_debug("try to open %s\n", fname);
146 fd = open(fname, O_RDONLY);
154 static const char * const probe_usage[] = {
155 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
156 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
157 "perf probe [<options>] --del '[GROUP:]EVENT' ...",
162 static const struct option options[] = {
163 OPT_BOOLEAN('v', "verbose", &verbose,
164 "be more verbose (show parsed arguments, etc)"),
166 OPT_STRING('k', "vmlinux", &session.vmlinux, "file",
167 "vmlinux/module pathname"),
169 OPT_BOOLEAN('l', "list", &listing, "list up current probe events"),
170 OPT_CALLBACK('d', "del", NULL, "[GROUP:]EVENT", "delete a probe event.",
171 opt_del_probe_event),
172 OPT_CALLBACK('a', "add", NULL,
174 "FUNC[+OFFS|%return] [ARG ...]",
176 "FUNC[+OFFS|%return|:RLN][@SRC]|SRC:ALN [ARG ...]",
178 "probe point definition, where\n"
179 "\t\tGRP:\tGroup name (optional)\n"
180 "\t\tNAME:\tEvent name\n"
181 "\t\tFUNC:\tFunction name\n"
182 "\t\tOFFS:\tOffset from function entry (in byte)\n"
183 "\t\t%return:\tPut the probe at function return\n"
185 "\t\tARG:\tProbe argument (only \n"
187 "\t\tSRC:\tSource code path\n"
188 "\t\tRLN:\tRelative line number from function entry.\n"
189 "\t\tALN:\tAbsolute line number in file.\n"
190 "\t\tARG:\tProbe argument (local variable name or\n"
192 "\t\t\tkprobe-tracer argument format.)\n",
193 opt_add_probe_event),
197 int cmd_probe(int argc, const char **argv, const char *prefix __used)
203 struct probe_point *pp;
205 argc = parse_options(argc, argv, options, probe_usage,
206 PARSE_OPT_STOP_AT_NON_OPTION);
208 parse_probe_event_argv(argc, argv);
210 if ((session.nr_probe == 0 && !session.dellist && !listing))
211 usage_with_options(probe_usage, options);
214 if (session.nr_probe != 0 || session.dellist) {
215 pr_warning(" Error: Don't use --list with"
217 usage_with_options(probe_usage, options);
219 show_perf_probe_events();
223 if (session.dellist) {
224 del_trace_kprobe_events(session.dellist);
225 strlist__delete(session.dellist);
226 if (session.nr_probe == 0)
230 if (session.need_dwarf)
232 die("Debuginfo-analysis is not supported");
233 #else /* !NO_LIBDWARF */
234 pr_debug("Some probes require debuginfo.\n");
236 if (session.vmlinux) {
237 pr_debug("Try to open %s.", session.vmlinux);
238 fd = open(session.vmlinux, O_RDONLY);
240 fd = open_default_vmlinux();
242 if (session.need_dwarf)
243 die("Could not open debuginfo file.");
245 pr_debug("Could not open vmlinux/module file."
246 " Try to use symbols.\n");
250 /* Searching probe points */
251 for (i = 0; i < session.nr_probe; i++) {
252 pp = &session.probes[i];
256 lseek(fd, SEEK_SET, 0);
257 ret = find_probepoint(fd, pp);
259 if (session.need_dwarf)
260 die("Could not analyze debuginfo.");
262 pr_warning("An error occurred in debuginfo analysis. Try to use symbols.\n");
265 if (ret == 0) /* No error but failed to find probe point. */
266 die("No probe point found.");
271 #endif /* !NO_LIBDWARF */
273 /* Synthesize probes without dwarf */
274 for (i = 0; i < session.nr_probe; i++) {
275 pp = &session.probes[i];
276 if (pp->found) /* This probe is already found. */
279 ret = synthesize_trace_kprobe_event(pp);
281 die("probe point definition becomes too long.");
283 die("Failed to synthesize a probe point.");
286 /* Settng up probe points */
287 add_trace_kprobe_events(session.probes, session.nr_probe);