Commit | Line | Data |
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4ea42b18 MH |
1 | /* |
2 | * builtin-probe.c | |
3 | * | |
4 | * Builtin probe command: Set up probe events by C expression | |
5 | * | |
6 | * Written by Masami Hiramatsu <mhiramat@redhat.com> | |
7 | * | |
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. | |
12 | * | |
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. | |
17 | * | |
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. | |
21 | * | |
22 | */ | |
23 | #define _GNU_SOURCE | |
24 | #include <sys/utsname.h> | |
25 | #include <sys/types.h> | |
26 | #include <sys/stat.h> | |
27 | #include <fcntl.h> | |
28 | #include <errno.h> | |
29 | #include <stdio.h> | |
30 | #include <unistd.h> | |
31 | #include <stdlib.h> | |
32 | #include <string.h> | |
33 | ||
34 | #undef _GNU_SOURCE | |
35 | #include "perf.h" | |
36 | #include "builtin.h" | |
37 | #include "util/util.h" | |
fa28244d | 38 | #include "util/strlist.h" |
89c69c0e MH |
39 | #include "util/event.h" |
40 | #include "util/debug.h" | |
4ea42b18 MH |
41 | #include "util/parse-options.h" |
42 | #include "util/parse-events.h" /* For debugfs_path */ | |
43 | #include "util/probe-finder.h" | |
50656eec | 44 | #include "util/probe-event.h" |
4ea42b18 MH |
45 | |
46 | /* Default vmlinux search paths */ | |
f984f03d | 47 | #define NR_SEARCH_PATH 4 |
4ea42b18 MH |
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 */ | |
f984f03d | 52 | "./vmlinux", /* CWD */ |
4ea42b18 MH |
53 | }; |
54 | ||
55 | #define MAX_PATH_LEN 256 | |
56 | #define MAX_PROBES 128 | |
57 | ||
58 | /* Session management structure */ | |
59 | static struct { | |
60 | char *vmlinux; | |
61 | char *release; | |
23e8ec0d | 62 | int need_dwarf; |
4ea42b18 MH |
63 | int nr_probe; |
64 | struct probe_point probes[MAX_PROBES]; | |
fa28244d | 65 | struct strlist *dellist; |
4ea42b18 MH |
66 | } session; |
67 | ||
4de189fe MH |
68 | static bool listing; |
69 | ||
253977b0 MH |
70 | /* Parse an event definition. Note that any error must die. */ |
71 | static void parse_probe_event(const char *str) | |
4ea42b18 | 72 | { |
4ea42b18 | 73 | struct probe_point *pp = &session.probes[session.nr_probe]; |
4ea42b18 | 74 | |
b7cb10e7 | 75 | pr_debug("probe-definition(%d): %s\n", session.nr_probe, str); |
4ea42b18 | 76 | if (++session.nr_probe == MAX_PROBES) |
50656eec | 77 | die("Too many probes (> %d) are specified.", MAX_PROBES); |
4ea42b18 | 78 | |
50656eec MH |
79 | /* Parse perf-probe event into probe_point */ |
80 | session.need_dwarf = parse_perf_probe_event(str, pp); | |
23e8ec0d | 81 | |
b7cb10e7 | 82 | pr_debug("%d arguments\n", pp->nr_args); |
46ab4926 MH |
83 | } |
84 | ||
d1bde3f7 MH |
85 | static void parse_probe_event_argv(int argc, const char **argv) |
86 | { | |
87 | int i, len; | |
88 | char *buf; | |
89 | ||
90 | /* Bind up rest arguments */ | |
91 | len = 0; | |
92 | for (i = 0; i < argc; i++) | |
93 | len += strlen(argv[i]) + 1; | |
94 | buf = zalloc(len + 1); | |
95 | if (!buf) | |
96 | die("Failed to allocate memory for binding arguments."); | |
97 | len = 0; | |
98 | for (i = 0; i < argc; i++) | |
99 | len += sprintf(&buf[len], "%s ", argv[i]); | |
100 | parse_probe_event(buf); | |
101 | free(buf); | |
102 | } | |
103 | ||
253977b0 | 104 | static int opt_add_probe_event(const struct option *opt __used, |
46ab4926 MH |
105 | const char *str, int unset __used) |
106 | { | |
107 | if (str) | |
253977b0 | 108 | parse_probe_event(str); |
4ea42b18 MH |
109 | return 0; |
110 | } | |
111 | ||
fa28244d MH |
112 | static int opt_del_probe_event(const struct option *opt __used, |
113 | const char *str, int unset __used) | |
114 | { | |
115 | if (str) { | |
116 | if (!session.dellist) | |
117 | session.dellist = strlist__new(true, NULL); | |
118 | strlist__add(session.dellist, str); | |
119 | } | |
120 | return 0; | |
121 | } | |
122 | ||
23e8ec0d | 123 | #ifndef NO_LIBDWARF |
4ea42b18 MH |
124 | static int open_default_vmlinux(void) |
125 | { | |
126 | struct utsname uts; | |
127 | char fname[MAX_PATH_LEN]; | |
128 | int fd, ret, i; | |
129 | ||
130 | ret = uname(&uts); | |
131 | if (ret) { | |
b7cb10e7 | 132 | pr_debug("uname() failed.\n"); |
4ea42b18 MH |
133 | return -errno; |
134 | } | |
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) { | |
b7cb10e7 | 140 | pr_debug("Filename(%d,%s) is too long.\n", i, |
89c69c0e | 141 | uts.release); |
4ea42b18 MH |
142 | errno = E2BIG; |
143 | return -E2BIG; | |
144 | } | |
b7cb10e7 | 145 | pr_debug("try to open %s\n", fname); |
4ea42b18 MH |
146 | fd = open(fname, O_RDONLY); |
147 | if (fd >= 0) | |
148 | break; | |
149 | } | |
150 | return fd; | |
151 | } | |
23e8ec0d | 152 | #endif |
4ea42b18 MH |
153 | |
154 | static const char * const probe_usage[] = { | |
46ab4926 MH |
155 | "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]", |
156 | "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]", | |
fa28244d | 157 | "perf probe [<options>] --del '[GROUP:]EVENT' ...", |
4de189fe | 158 | "perf probe --list", |
4ea42b18 MH |
159 | NULL |
160 | }; | |
161 | ||
162 | static const struct option options[] = { | |
89c69c0e MH |
163 | OPT_BOOLEAN('v', "verbose", &verbose, |
164 | "be more verbose (show parsed arguments, etc)"), | |
23e8ec0d | 165 | #ifndef NO_LIBDWARF |
4ea42b18 MH |
166 | OPT_STRING('k', "vmlinux", &session.vmlinux, "file", |
167 | "vmlinux/module pathname"), | |
23e8ec0d | 168 | #endif |
fa28244d MH |
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), | |
46ab4926 | 172 | OPT_CALLBACK('a', "add", NULL, |
23e8ec0d | 173 | #ifdef NO_LIBDWARF |
253977b0 | 174 | "FUNC[+OFFS|%return] [ARG ...]", |
23e8ec0d | 175 | #else |
b0ef0732 | 176 | "FUNC[+OFFS|%return|:RLN][@SRC]|SRC:ALN [ARG ...]", |
23e8ec0d | 177 | #endif |
4ea42b18 | 178 | "probe point definition, where\n" |
4ea42b18 MH |
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" | |
253977b0 | 183 | "\t\t%return:\tPut the probe at function return\n" |
23e8ec0d MH |
184 | #ifdef NO_LIBDWARF |
185 | "\t\tARG:\tProbe argument (only \n" | |
186 | #else | |
4ea42b18 | 187 | "\t\tSRC:\tSource code path\n" |
b0ef0732 MH |
188 | "\t\tRLN:\tRelative line number from function entry.\n" |
189 | "\t\tALN:\tAbsolute line number in file.\n" | |
4ea42b18 | 190 | "\t\tARG:\tProbe argument (local variable name or\n" |
23e8ec0d | 191 | #endif |
50656eec | 192 | "\t\t\tkprobe-tracer argument format.)\n", |
253977b0 | 193 | opt_add_probe_event), |
4ea42b18 MH |
194 | OPT_END() |
195 | }; | |
196 | ||
4ea42b18 MH |
197 | int cmd_probe(int argc, const char **argv, const char *prefix __used) |
198 | { | |
d1bde3f7 | 199 | int i, ret; |
bdad0db7 XG |
200 | #ifndef NO_LIBDWARF |
201 | int fd; | |
202 | #endif | |
4ea42b18 | 203 | struct probe_point *pp; |
4ea42b18 MH |
204 | |
205 | argc = parse_options(argc, argv, options, probe_usage, | |
46ab4926 | 206 | PARSE_OPT_STOP_AT_NON_OPTION); |
d1bde3f7 MH |
207 | if (argc > 0) |
208 | parse_probe_event_argv(argc, argv); | |
46ab4926 | 209 | |
fa28244d | 210 | if ((session.nr_probe == 0 && !session.dellist && !listing)) |
4ea42b18 MH |
211 | usage_with_options(probe_usage, options); |
212 | ||
4de189fe | 213 | if (listing) { |
fa28244d MH |
214 | if (session.nr_probe != 0 || session.dellist) { |
215 | pr_warning(" Error: Don't use --list with" | |
216 | " --add/--del.\n"); | |
217 | usage_with_options(probe_usage, options); | |
218 | } | |
4de189fe MH |
219 | show_perf_probe_events(); |
220 | return 0; | |
221 | } | |
222 | ||
fa28244d MH |
223 | if (session.dellist) { |
224 | del_trace_kprobe_events(session.dellist); | |
225 | strlist__delete(session.dellist); | |
226 | if (session.nr_probe == 0) | |
227 | return 0; | |
228 | } | |
229 | ||
23e8ec0d | 230 | if (session.need_dwarf) |
a225a1d9 | 231 | #ifdef NO_LIBDWARF |
50656eec | 232 | die("Debuginfo-analysis is not supported"); |
a225a1d9 | 233 | #else /* !NO_LIBDWARF */ |
f41b1e43 | 234 | pr_debug("Some probes require debuginfo.\n"); |
4ea42b18 | 235 | |
f984f03d MH |
236 | if (session.vmlinux) { |
237 | pr_debug("Try to open %s.", session.vmlinux); | |
4ea42b18 | 238 | fd = open(session.vmlinux, O_RDONLY); |
f984f03d | 239 | } else |
4ea42b18 | 240 | fd = open_default_vmlinux(); |
a225a1d9 MH |
241 | if (fd < 0) { |
242 | if (session.need_dwarf) | |
f984f03d | 243 | die("Could not open debuginfo file."); |
a225a1d9 | 244 | |
d3a2dbf8 MH |
245 | pr_debug("Could not open vmlinux/module file." |
246 | " Try to use symbols.\n"); | |
a225a1d9 MH |
247 | goto end_dwarf; |
248 | } | |
4ea42b18 MH |
249 | |
250 | /* Searching probe points */ | |
d1bde3f7 MH |
251 | for (i = 0; i < session.nr_probe; i++) { |
252 | pp = &session.probes[i]; | |
4ea42b18 MH |
253 | if (pp->found) |
254 | continue; | |
255 | ||
256 | lseek(fd, SEEK_SET, 0); | |
257 | ret = find_probepoint(fd, pp); | |
a225a1d9 MH |
258 | if (ret < 0) { |
259 | if (session.need_dwarf) | |
260 | die("Could not analyze debuginfo."); | |
261 | ||
262 | pr_warning("An error occurred in debuginfo analysis. Try to use symbols.\n"); | |
263 | break; | |
264 | } | |
265 | if (ret == 0) /* No error but failed to find probe point. */ | |
266 | die("No probe point found."); | |
4ea42b18 MH |
267 | } |
268 | close(fd); | |
269 | ||
a225a1d9 | 270 | end_dwarf: |
23e8ec0d MH |
271 | #endif /* !NO_LIBDWARF */ |
272 | ||
a225a1d9 | 273 | /* Synthesize probes without dwarf */ |
d1bde3f7 MH |
274 | for (i = 0; i < session.nr_probe; i++) { |
275 | pp = &session.probes[i]; | |
a225a1d9 MH |
276 | if (pp->found) /* This probe is already found. */ |
277 | continue; | |
278 | ||
50656eec | 279 | ret = synthesize_trace_kprobe_event(pp); |
a225a1d9 | 280 | if (ret == -E2BIG) |
50656eec | 281 | die("probe point definition becomes too long."); |
a225a1d9 MH |
282 | else if (ret < 0) |
283 | die("Failed to synthesize a probe point."); | |
284 | } | |
285 | ||
4ea42b18 | 286 | /* Settng up probe points */ |
50656eec | 287 | add_trace_kprobe_events(session.probes, session.nr_probe); |
4ea42b18 MH |
288 | return 0; |
289 | } | |
290 |