4 * Builtin record command: Record the profile of a workload
5 * (or a CPU, or a PID) into the perf.data output file - for
6 * later analysis via perf report.
8 #define _FILE_OFFSET_BITS 64
14 #include "util/build-id.h"
15 #include "util/util.h"
16 #include "util/parse-options.h"
17 #include "util/parse-events.h"
19 #include "util/header.h"
20 #include "util/event.h"
21 #include "util/evlist.h"
22 #include "util/evsel.h"
23 #include "util/debug.h"
24 #include "util/session.h"
25 #include "util/symbol.h"
26 #include "util/cpumap.h"
27 #include "util/thread_map.h"
33 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
40 static u64 user_interval
= ULLONG_MAX
;
41 static u64 default_interval
= 0;
43 static unsigned int page_size
;
44 static unsigned int mmap_pages
= 128;
45 static unsigned int user_freq
= UINT_MAX
;
46 static int freq
= 1000;
48 static int pipe_output
= 0;
49 static const char *output_name
= NULL
;
51 static int realtime_prio
= 0;
52 static bool nodelay
= false;
53 static bool raw_samples
= false;
54 static bool sample_id_all_avail
= true;
55 static bool system_wide
= false;
56 static pid_t target_pid
= -1;
57 static pid_t target_tid
= -1;
58 static pid_t child_pid
= -1;
59 static bool no_inherit
= false;
60 static enum write_mode_t write_mode
= WRITE_FORCE
;
61 static bool call_graph
= false;
62 static bool inherit_stat
= false;
63 static bool no_samples
= false;
64 static bool sample_address
= false;
65 static bool sample_time
= false;
66 static bool no_buildid
= false;
67 static bool no_buildid_cache
= false;
68 static struct perf_evlist
*evsel_list
;
70 static long samples
= 0;
71 static u64 bytes_written
= 0;
73 static int file_new
= 1;
74 static off_t post_processing_offset
;
76 static struct perf_session
*session
;
77 static const char *cpu_list
;
79 static void advance_output(size_t size
)
81 bytes_written
+= size
;
84 static void write_output(void *buf
, size_t size
)
87 int ret
= write(output
, buf
, size
);
90 die("failed to write");
99 static int process_synthesized_event(union perf_event
*event
,
100 struct perf_sample
*sample __used
,
101 struct perf_session
*self __used
)
103 write_output(event
, event
->header
.size
);
107 static void mmap_read(struct perf_mmap
*md
)
109 unsigned int head
= perf_mmap__read_head(md
);
110 unsigned int old
= md
->prev
;
111 unsigned char *data
= md
->base
+ page_size
;
122 if ((old
& md
->mask
) + size
!= (head
& md
->mask
)) {
123 buf
= &data
[old
& md
->mask
];
124 size
= md
->mask
+ 1 - (old
& md
->mask
);
127 write_output(buf
, size
);
130 buf
= &data
[old
& md
->mask
];
134 write_output(buf
, size
);
137 perf_mmap__write_tail(md
, old
);
140 static volatile int done
= 0;
141 static volatile int signr
= -1;
143 static void sig_handler(int sig
)
149 static void sig_atexit(void)
152 kill(child_pid
, SIGTERM
);
154 if (signr
== -1 || signr
== SIGUSR1
)
157 signal(signr
, SIG_DFL
);
158 kill(getpid(), signr
);
161 static void config_attr(struct perf_evsel
*evsel
, struct perf_evlist
*evlist
)
163 struct perf_event_attr
*attr
= &evsel
->attr
;
164 int track
= !evsel
->idx
; /* only the first counter needs these */
166 attr
->read_format
= PERF_FORMAT_TOTAL_TIME_ENABLED
|
167 PERF_FORMAT_TOTAL_TIME_RUNNING
|
170 attr
->sample_type
|= PERF_SAMPLE_IP
| PERF_SAMPLE_TID
;
172 if (evlist
->nr_entries
> 1)
173 attr
->sample_type
|= PERF_SAMPLE_ID
;
176 * We default some events to a 1 default interval. But keep
177 * it a weak assumption overridable by the user.
179 if (!attr
->sample_period
|| (user_freq
!= UINT_MAX
&&
180 user_interval
!= ULLONG_MAX
)) {
182 attr
->sample_type
|= PERF_SAMPLE_PERIOD
;
184 attr
->sample_freq
= freq
;
186 attr
->sample_period
= default_interval
;
191 attr
->sample_freq
= 0;
194 attr
->inherit_stat
= 1;
196 if (sample_address
) {
197 attr
->sample_type
|= PERF_SAMPLE_ADDR
;
198 attr
->mmap_data
= track
;
202 attr
->sample_type
|= PERF_SAMPLE_CALLCHAIN
;
205 attr
->sample_type
|= PERF_SAMPLE_CPU
;
207 if (sample_id_all_avail
&&
208 (sample_time
|| system_wide
|| !no_inherit
|| cpu_list
))
209 attr
->sample_type
|= PERF_SAMPLE_TIME
;
212 attr
->sample_type
|= PERF_SAMPLE_TIME
;
213 attr
->sample_type
|= PERF_SAMPLE_RAW
;
214 attr
->sample_type
|= PERF_SAMPLE_CPU
;
219 attr
->wakeup_events
= 1;
225 if (target_pid
== -1 && target_tid
== -1 && !system_wide
) {
227 attr
->enable_on_exec
= 1;
231 static bool perf_evlist__equal(struct perf_evlist
*evlist
,
232 struct perf_evlist
*other
)
234 struct perf_evsel
*pos
, *pair
;
236 if (evlist
->nr_entries
!= other
->nr_entries
)
239 pair
= list_entry(other
->entries
.next
, struct perf_evsel
, node
);
241 list_for_each_entry(pos
, &evlist
->entries
, node
) {
242 if (memcmp(&pos
->attr
, &pair
->attr
, sizeof(pos
->attr
) != 0))
244 pair
= list_entry(pair
->node
.next
, struct perf_evsel
, node
);
250 static void open_counters(struct perf_evlist
*evlist
)
252 struct perf_evsel
*pos
;
254 list_for_each_entry(pos
, &evlist
->entries
, node
) {
255 struct perf_event_attr
*attr
= &pos
->attr
;
257 * Check if parse_single_tracepoint_event has already asked for
260 * XXX this is kludgy but short term fix for problems introduced by
261 * eac23d1c that broke 'perf script' by having different sample_types
262 * when using multiple tracepoint events when we use a perf binary
263 * that tries to use sample_id_all on an older kernel.
265 * We need to move counter creation to perf_session, support
266 * different sample_types, etc.
268 bool time_needed
= attr
->sample_type
& PERF_SAMPLE_TIME
;
270 config_attr(pos
, evlist
);
272 attr
->sample_id_all
= sample_id_all_avail
? 1 : 0;
274 if (perf_evsel__open(pos
, evlist
->cpus
, evlist
->threads
, group
,
278 if (err
== EPERM
|| err
== EACCES
)
279 die("Permission error - are you root?\n"
280 "\t Consider tweaking"
281 " /proc/sys/kernel/perf_event_paranoid.\n");
282 else if (err
== ENODEV
&& cpu_list
) {
283 die("No such device - did you specify"
284 " an out-of-range profile CPU?\n");
285 } else if (err
== EINVAL
&& sample_id_all_avail
) {
287 * Old kernel, no attr->sample_id_type_all field
289 sample_id_all_avail
= false;
290 if (!sample_time
&& !raw_samples
&& !time_needed
)
291 attr
->sample_type
&= ~PERF_SAMPLE_TIME
;
293 goto retry_sample_id
;
297 * If it's cycles then fall back to hrtimer
298 * based cpu-clock-tick sw counter, which
299 * is always available even if no PMU support:
301 if (attr
->type
== PERF_TYPE_HARDWARE
302 && attr
->config
== PERF_COUNT_HW_CPU_CYCLES
) {
305 warning(" ... trying to fall back to cpu-clock-ticks\n");
306 attr
->type
= PERF_TYPE_SOFTWARE
;
307 attr
->config
= PERF_COUNT_SW_CPU_CLOCK
;
311 error("sys_perf_event_open() syscall returned with %d (%s). /bin/dmesg may provide additional information.\n",
314 #if defined(__i386__) || defined(__x86_64__)
315 if (attr
->type
== PERF_TYPE_HARDWARE
&& err
== EOPNOTSUPP
)
316 die("No hardware sampling interrupt available."
317 " No APIC? If so then you can boot the kernel"
318 " with the \"lapic\" boot parameter to"
319 " force-enable it.\n");
322 die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
326 if (perf_evlist__set_filters(evlist
)) {
327 error("failed to set filter with %d (%s)\n", errno
,
332 if (perf_evlist__mmap(evlist
, mmap_pages
, false) < 0)
333 die("failed to mmap with %d (%s)\n", errno
, strerror(errno
));
336 session
->evlist
= evlist
;
338 if (!perf_evlist__equal(session
->evlist
, evlist
)) {
339 fprintf(stderr
, "incompatible append\n");
344 perf_session__update_sample_type(session
);
347 static int process_buildids(void)
349 u64 size
= lseek(output
, 0, SEEK_CUR
);
354 session
->fd
= output
;
355 return __perf_session__process_events(session
, post_processing_offset
,
356 size
- post_processing_offset
,
357 size
, &build_id__mark_dso_hit_ops
);
360 static void atexit_header(void)
363 session
->header
.data_size
+= bytes_written
;
367 perf_session__write_header(session
, evsel_list
, output
, true);
368 perf_session__delete(session
);
369 perf_evlist__delete(evsel_list
);
374 static void perf_event__synthesize_guest_os(struct machine
*machine
, void *data
)
377 struct perf_session
*psession
= data
;
379 if (machine__is_host(machine
))
383 *As for guest kernel when processing subcommand record&report,
384 *we arrange module mmap prior to guest kernel mmap and trigger
385 *a preload dso because default guest module symbols are loaded
386 *from guest kallsyms instead of /lib/modules/XXX/XXX. This
387 *method is used to avoid symbol missing when the first addr is
388 *in module instead of in guest kernel.
390 err
= perf_event__synthesize_modules(process_synthesized_event
,
393 pr_err("Couldn't record guest kernel [%d]'s reference"
394 " relocation symbol.\n", machine
->pid
);
397 * We use _stext for guest kernel because guest kernel's /proc/kallsyms
398 * have no _text sometimes.
400 err
= perf_event__synthesize_kernel_mmap(process_synthesized_event
,
401 psession
, machine
, "_text");
403 err
= perf_event__synthesize_kernel_mmap(process_synthesized_event
,
407 pr_err("Couldn't record guest kernel [%d]'s reference"
408 " relocation symbol.\n", machine
->pid
);
411 static struct perf_event_header finished_round_event
= {
412 .size
= sizeof(struct perf_event_header
),
413 .type
= PERF_RECORD_FINISHED_ROUND
,
416 static void mmap_read_all(void)
420 for (i
= 0; i
< evsel_list
->cpus
->nr
; i
++) {
421 if (evsel_list
->mmap
[i
].base
)
422 mmap_read(&evsel_list
->mmap
[i
]);
425 if (perf_header__has_feat(&session
->header
, HEADER_TRACE_INFO
))
426 write_output(&finished_round_event
, sizeof(finished_round_event
));
429 static int __cmd_record(int argc
, const char **argv
)
435 unsigned long waking
= 0;
436 int child_ready_pipe
[2], go_pipe
[2];
437 const bool forks
= argc
> 0;
439 struct machine
*machine
;
441 page_size
= sysconf(_SC_PAGE_SIZE
);
444 signal(SIGCHLD
, sig_handler
);
445 signal(SIGINT
, sig_handler
);
446 signal(SIGUSR1
, sig_handler
);
448 if (forks
&& (pipe(child_ready_pipe
) < 0 || pipe(go_pipe
) < 0)) {
449 perror("failed to create pipes");
454 if (!fstat(STDOUT_FILENO
, &st
) && S_ISFIFO(st
.st_mode
))
457 output_name
= "perf.data";
460 if (!strcmp(output_name
, "-"))
462 else if (!stat(output_name
, &st
) && st
.st_size
) {
463 if (write_mode
== WRITE_FORCE
) {
464 char oldname
[PATH_MAX
];
465 snprintf(oldname
, sizeof(oldname
), "%s.old",
468 rename(output_name
, oldname
);
470 } else if (write_mode
== WRITE_APPEND
) {
471 write_mode
= WRITE_FORCE
;
475 flags
= O_CREAT
|O_RDWR
;
476 if (write_mode
== WRITE_APPEND
)
482 output
= STDOUT_FILENO
;
484 output
= open(output_name
, flags
, S_IRUSR
| S_IWUSR
);
486 perror("failed to create output file");
490 session
= perf_session__new(output_name
, O_WRONLY
,
491 write_mode
== WRITE_FORCE
, false, NULL
);
492 if (session
== NULL
) {
493 pr_err("Not enough memory for reading perf file header\n");
498 perf_header__set_feat(&session
->header
, HEADER_BUILD_ID
);
501 err
= perf_session__read_header(session
, output
);
503 goto out_delete_session
;
506 if (have_tracepoints(&evsel_list
->entries
))
507 perf_header__set_feat(&session
->header
, HEADER_TRACE_INFO
);
512 perror("failed to fork");
519 close(child_ready_pipe
[0]);
521 fcntl(go_pipe
[0], F_SETFD
, FD_CLOEXEC
);
524 * Do a dummy execvp to get the PLT entry resolved,
525 * so we avoid the resolver overhead on the real
528 execvp("", (char **)argv
);
531 * Tell the parent we're ready to go
533 close(child_ready_pipe
[1]);
536 * Wait until the parent tells us to go.
538 if (read(go_pipe
[0], &buf
, 1) == -1)
539 perror("unable to read pipe");
541 execvp(argv
[0], (char **)argv
);
544 kill(getppid(), SIGUSR1
);
548 if (!system_wide
&& target_tid
== -1 && target_pid
== -1)
549 evsel_list
->threads
->map
[0] = child_pid
;
551 close(child_ready_pipe
[1]);
554 * wait for child to settle
556 if (read(child_ready_pipe
[0], &buf
, 1) == -1) {
557 perror("unable to read pipe");
560 close(child_ready_pipe
[0]);
563 open_counters(evsel_list
);
566 * perf_session__delete(session) will be called at atexit_header()
568 atexit(atexit_header
);
571 err
= perf_header__write_pipe(output
);
574 } else if (file_new
) {
575 err
= perf_session__write_header(session
, evsel_list
,
581 post_processing_offset
= lseek(output
, 0, SEEK_CUR
);
584 err
= perf_session__synthesize_attrs(session
,
585 process_synthesized_event
);
587 pr_err("Couldn't synthesize attrs.\n");
591 err
= perf_event__synthesize_event_types(process_synthesized_event
,
594 pr_err("Couldn't synthesize event_types.\n");
598 if (have_tracepoints(&evsel_list
->entries
)) {
600 * FIXME err <= 0 here actually means that
601 * there were no tracepoints so its not really
602 * an error, just that we don't need to
603 * synthesize anything. We really have to
604 * return this more properly and also
605 * propagate errors that now are calling die()
607 err
= perf_event__synthesize_tracing_data(output
, evsel_list
,
608 process_synthesized_event
,
611 pr_err("Couldn't record tracing data.\n");
618 machine
= perf_session__find_host_machine(session
);
620 pr_err("Couldn't find native kernel information.\n");
624 err
= perf_event__synthesize_kernel_mmap(process_synthesized_event
,
625 session
, machine
, "_text");
627 err
= perf_event__synthesize_kernel_mmap(process_synthesized_event
,
628 session
, machine
, "_stext");
630 pr_err("Couldn't record kernel reference relocation symbol\n"
631 "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
632 "Check /proc/kallsyms permission or run as root.\n");
634 err
= perf_event__synthesize_modules(process_synthesized_event
,
637 pr_err("Couldn't record kernel module information.\n"
638 "Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
639 "Check /proc/modules permission or run as root.\n");
642 perf_session__process_machines(session
,
643 perf_event__synthesize_guest_os
);
646 perf_event__synthesize_thread_map(evsel_list
->threads
,
647 process_synthesized_event
,
650 perf_event__synthesize_threads(process_synthesized_event
,
654 struct sched_param param
;
656 param
.sched_priority
= realtime_prio
;
657 if (sched_setscheduler(0, SCHED_FIFO
, ¶m
)) {
658 pr_err("Could not set realtime priority.\n");
675 if (hits
== samples
) {
678 err
= poll(evsel_list
->pollfd
, evsel_list
->nr_fds
, -1);
683 for (i
= 0; i
< evsel_list
->cpus
->nr
; i
++) {
684 struct perf_evsel
*pos
;
686 list_for_each_entry(pos
, &evsel_list
->entries
, node
) {
688 thread
< evsel_list
->threads
->nr
;
690 ioctl(FD(pos
, i
, thread
),
691 PERF_EVENT_IOC_DISABLE
);
697 if (quiet
|| signr
== SIGUSR1
)
700 fprintf(stderr
, "[ perf record: Woken up %ld times to write data ]\n", waking
);
703 * Approximate RIP event size: 24 bytes.
706 "[ perf record: Captured and wrote %.3f MB %s (~%" PRIu64
" samples) ]\n",
707 (double)bytes_written
/ 1024.0 / 1024.0,
714 perf_session__delete(session
);
718 static const char * const record_usage
[] = {
719 "perf record [<options>] [<command>]",
720 "perf record [<options>] -- <command> [<options>]",
724 static bool force
, append_file
;
726 const struct option record_options
[] = {
727 OPT_CALLBACK('e', "event", &evsel_list
, "event",
728 "event selector. use 'perf list' to list available events",
730 OPT_CALLBACK(0, "filter", &evsel_list
, "filter",
731 "event filter", parse_filter
),
732 OPT_INTEGER('p', "pid", &target_pid
,
733 "record events on existing process id"),
734 OPT_INTEGER('t', "tid", &target_tid
,
735 "record events on existing thread id"),
736 OPT_INTEGER('r', "realtime", &realtime_prio
,
737 "collect data with this RT SCHED_FIFO priority"),
738 OPT_BOOLEAN('D', "no-delay", &nodelay
,
739 "collect data without buffering"),
740 OPT_BOOLEAN('R', "raw-samples", &raw_samples
,
741 "collect raw sample records from all opened counters"),
742 OPT_BOOLEAN('a', "all-cpus", &system_wide
,
743 "system-wide collection from all CPUs"),
744 OPT_BOOLEAN('A', "append", &append_file
,
745 "append to the output file to do incremental profiling"),
746 OPT_STRING('C', "cpu", &cpu_list
, "cpu",
747 "list of cpus to monitor"),
748 OPT_BOOLEAN('f', "force", &force
,
749 "overwrite existing data file (deprecated)"),
750 OPT_U64('c', "count", &user_interval
, "event period to sample"),
751 OPT_STRING('o', "output", &output_name
, "file",
753 OPT_BOOLEAN('i', "no-inherit", &no_inherit
,
754 "child tasks do not inherit counters"),
755 OPT_UINTEGER('F', "freq", &user_freq
, "profile at this frequency"),
756 OPT_UINTEGER('m', "mmap-pages", &mmap_pages
, "number of mmap data pages"),
757 OPT_BOOLEAN('g', "call-graph", &call_graph
,
758 "do call-graph (stack chain/backtrace) recording"),
759 OPT_INCR('v', "verbose", &verbose
,
760 "be more verbose (show counter open errors, etc)"),
761 OPT_BOOLEAN('q', "quiet", &quiet
, "don't print any message"),
762 OPT_BOOLEAN('s', "stat", &inherit_stat
,
763 "per thread counts"),
764 OPT_BOOLEAN('d', "data", &sample_address
,
766 OPT_BOOLEAN('T', "timestamp", &sample_time
, "Sample timestamps"),
767 OPT_BOOLEAN('n', "no-samples", &no_samples
,
769 OPT_BOOLEAN('N', "no-buildid-cache", &no_buildid_cache
,
770 "do not update the buildid cache"),
771 OPT_BOOLEAN('B', "no-buildid", &no_buildid
,
772 "do not collect buildids in perf.data"),
773 OPT_CALLBACK('G', "cgroup", &evsel_list
, "name",
774 "monitor event in cgroup name only",
779 int cmd_record(int argc
, const char **argv
, const char *prefix __used
)
782 struct perf_evsel
*pos
;
784 evsel_list
= perf_evlist__new(NULL
, NULL
);
785 if (evsel_list
== NULL
)
788 argc
= parse_options(argc
, argv
, record_options
, record_usage
,
789 PARSE_OPT_STOP_AT_NON_OPTION
);
790 if (!argc
&& target_pid
== -1 && target_tid
== -1 &&
791 !system_wide
&& !cpu_list
)
792 usage_with_options(record_usage
, record_options
);
794 if (force
&& append_file
) {
795 fprintf(stderr
, "Can't overwrite and append at the same time."
796 " You need to choose between -f and -A");
797 usage_with_options(record_usage
, record_options
);
798 } else if (append_file
) {
799 write_mode
= WRITE_APPEND
;
801 write_mode
= WRITE_FORCE
;
804 if (nr_cgroups
&& !system_wide
) {
805 fprintf(stderr
, "cgroup monitoring only available in"
806 " system-wide mode\n");
807 usage_with_options(record_usage
, record_options
);
812 if (no_buildid_cache
|| no_buildid
)
813 disable_buildid_cache();
815 if (evsel_list
->nr_entries
== 0 &&
816 perf_evlist__add_default(evsel_list
) < 0) {
817 pr_err("Not enough memory for event selector list\n");
818 goto out_symbol_exit
;
821 if (target_pid
!= -1)
822 target_tid
= target_pid
;
824 if (perf_evlist__create_maps(evsel_list
, target_pid
,
825 target_tid
, cpu_list
) < 0)
826 usage_with_options(record_usage
, record_options
);
828 list_for_each_entry(pos
, &evsel_list
->entries
, node
) {
829 if (perf_evsel__alloc_fd(pos
, evsel_list
->cpus
->nr
,
830 evsel_list
->threads
->nr
) < 0)
832 if (perf_header__push_event(pos
->attr
.config
, event_name(pos
)))
836 if (perf_evlist__alloc_pollfd(evsel_list
) < 0)
839 if (user_interval
!= ULLONG_MAX
)
840 default_interval
= user_interval
;
841 if (user_freq
!= UINT_MAX
)
845 * User specified count overrides default frequency.
847 if (default_interval
)
850 default_interval
= freq
;
852 fprintf(stderr
, "frequency and count are zero, aborting\n");
857 err
= __cmd_record(argc
, argv
);
859 perf_evlist__delete_maps(evsel_list
);