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/event.h"
39 #include "util/debug.h"
40 #include "util/parse-options.h"
41 #include "util/parse-events.h" /* For debugfs_path */
42 #include "util/probe-finder.h"
43 #include "util/probe-event.h"
45 /* Default vmlinux search paths */
46 #define NR_SEARCH_PATH 3
47 const char *default_search_path
[NR_SEARCH_PATH
] = {
48 "/lib/modules/%s/build/vmlinux", /* Custom build kernel */
49 "/usr/lib/debug/lib/modules/%s/vmlinux", /* Red Hat debuginfo */
50 "/boot/vmlinux-debug-%s", /* Ubuntu */
53 #define MAX_PATH_LEN 256
54 #define MAX_PROBES 128
56 /* Session management structure */
62 struct probe_point probes
[MAX_PROBES
];
67 /* Parse an event definition. Note that any error must die. */
68 static void parse_probe_event(const char *str
)
70 struct probe_point
*pp
= &session
.probes
[session
.nr_probe
];
72 pr_debug("probe-definition(%d): %s\n", session
.nr_probe
, str
);
73 if (++session
.nr_probe
== MAX_PROBES
)
74 die("Too many probes (> %d) are specified.", MAX_PROBES
);
76 /* Parse perf-probe event into probe_point */
77 session
.need_dwarf
= parse_perf_probe_event(str
, pp
);
79 pr_debug("%d arguments\n", pp
->nr_args
);
82 static int opt_add_probe_event(const struct option
*opt __used
,
83 const char *str
, int unset __used
)
86 parse_probe_event(str
);
91 static int open_default_vmlinux(void)
94 char fname
[MAX_PATH_LEN
];
99 pr_debug("uname() failed.\n");
102 session
.release
= uts
.release
;
103 for (i
= 0; i
< NR_SEARCH_PATH
; i
++) {
104 ret
= snprintf(fname
, MAX_PATH_LEN
,
105 default_search_path
[i
], session
.release
);
106 if (ret
>= MAX_PATH_LEN
|| ret
< 0) {
107 pr_debug("Filename(%d,%s) is too long.\n", i
,
112 pr_debug("try to open %s\n", fname
);
113 fd
= open(fname
, O_RDONLY
);
121 static const char * const probe_usage
[] = {
122 "perf probe [<options>] 'PROBEDEF' ['PROBEDEF' ...]",
123 "perf probe [<options>] --add 'PROBEDEF' [--add 'PROBEDEF' ...]",
128 static const struct option options
[] = {
129 OPT_BOOLEAN('v', "verbose", &verbose
,
130 "be more verbose (show parsed arguments, etc)"),
132 OPT_STRING('k', "vmlinux", &session
.vmlinux
, "file",
133 "vmlinux/module pathname"),
135 OPT_BOOLEAN('l', "list", &listing
, "list up current probes"),
136 OPT_CALLBACK('a', "add", NULL
,
138 "FUNC[+OFFS|%return] [ARG ...]",
140 "FUNC[+OFFS|%return|:RLN][@SRC]|SRC:ALN [ARG ...]",
142 "probe point definition, where\n"
143 "\t\tGRP:\tGroup name (optional)\n"
144 "\t\tNAME:\tEvent name\n"
145 "\t\tFUNC:\tFunction name\n"
146 "\t\tOFFS:\tOffset from function entry (in byte)\n"
147 "\t\t%return:\tPut the probe at function return\n"
149 "\t\tARG:\tProbe argument (only \n"
151 "\t\tSRC:\tSource code path\n"
152 "\t\tRLN:\tRelative line number from function entry.\n"
153 "\t\tALN:\tAbsolute line number in file.\n"
154 "\t\tARG:\tProbe argument (local variable name or\n"
156 "\t\t\tkprobe-tracer argument format.)\n",
157 opt_add_probe_event
),
161 int cmd_probe(int argc
, const char **argv
, const char *prefix __used
)
167 struct probe_point
*pp
;
169 argc
= parse_options(argc
, argv
, options
, probe_usage
,
170 PARSE_OPT_STOP_AT_NON_OPTION
);
171 for (i
= 0; i
< argc
; i
++)
172 parse_probe_event(argv
[i
]);
174 if ((session
.nr_probe
== 0 && !listing
) ||
175 (session
.nr_probe
!= 0 && listing
))
176 usage_with_options(probe_usage
, options
);
179 show_perf_probe_events();
183 if (session
.need_dwarf
)
185 die("Debuginfo-analysis is not supported");
186 #else /* !NO_LIBDWARF */
187 pr_debug("Some probes require debuginfo.\n");
190 fd
= open(session
.vmlinux
, O_RDONLY
);
192 fd
= open_default_vmlinux();
194 if (session
.need_dwarf
)
195 die("Could not open vmlinux/module file.");
197 pr_warning("Could not open vmlinux/module file."
198 " Try to use symbols.\n");
202 /* Searching probe points */
203 for (j
= 0; j
< session
.nr_probe
; j
++) {
204 pp
= &session
.probes
[j
];
208 lseek(fd
, SEEK_SET
, 0);
209 ret
= find_probepoint(fd
, pp
);
211 if (session
.need_dwarf
)
212 die("Could not analyze debuginfo.");
214 pr_warning("An error occurred in debuginfo analysis. Try to use symbols.\n");
217 if (ret
== 0) /* No error but failed to find probe point. */
218 die("No probe point found.");
223 #endif /* !NO_LIBDWARF */
225 /* Synthesize probes without dwarf */
226 for (j
= 0; j
< session
.nr_probe
; j
++) {
227 pp
= &session
.probes
[j
];
228 if (pp
->found
) /* This probe is already found. */
231 ret
= synthesize_trace_kprobe_event(pp
);
233 die("probe point definition becomes too long.");
235 die("Failed to synthesize a probe point.");
238 /* Settng up probe points */
239 add_trace_kprobe_events(session
.probes
, session
.nr_probe
);