- 根目录:
- tools
- perf
- builtin-record.c
/*
* builtin-record.c
*
* Builtin record command: Record the profile of a workload
* (or a CPU, or a PID) into the perf.data output file - for
* later analysis via perf report.
*/
#define _FILE_OFFSET_BITS 64
#include "builtin.h"
#include "perf.h"
#include "util/build-id.h"
#include "util/util.h"
#include "util/parse-options.h"
#include "util/parse-events.h"
#include "util/header.h"
#include "util/event.h"
#include "util/evlist.h"
#include "util/evsel.h"
#include "util/debug.h"
#include "util/session.h"
#include "util/symbol.h"
#include "util/cpumap.h"
#include "util/thread_map.h"
#include <unistd.h>
#include <sched.h>
#include <sys/mman.h>
#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
enum write_mode_t {
WRITE_FORCE,
WRITE_APPEND
};
static u64 user_interval = ULLONG_MAX;
static u64 default_interval = 0;
static unsigned int page_size;
static unsigned int mmap_pages = UINT_MAX;
static unsigned int user_freq = UINT_MAX;
static int freq = 1000;
static int output;
static int pipe_output = 0;
static const char *output_name = NULL;
static int group = 0;
static int realtime_prio = 0;
static bool nodelay = false;
static bool raw_samples = false;
static bool sample_id_all_avail = true;
static bool system_wide = false;
static pid_t target_pid = -1;
static pid_t target_tid = -1;
static pid_t child_pid = -1;
static bool no_inherit = false;
static enum write_mode_t write_mode = WRITE_FORCE;
static bool call_graph = false;
static bool inherit_stat = false;
static bool no_samples = false;
static bool sample_address = false;
static bool sample_time = false;
static bool no_buildid = false;
static bool no_buildid_cache = false;
static struct perf_evlist *evsel_list;
static long samples = 0;
static u64 bytes_written = 0;
static int file_new = 1;
static off_t post_processing_offset;
static struct perf_session *session;
static const char *cpu_list;
static void advance_output(size_t size)
{
bytes_written += size;
}
static void write_output(void *buf, size_t size)
{
while (size) {
int ret = write(output, buf, size);
if (ret < 0)
die("failed to write");
size -= ret;
buf += ret;
bytes_written += ret;
}
}
static int process_synthesized_event(union perf_event *event,
struct perf_sample *sample __used,
struct perf_session *self __used)
{
write_output(event, event->header.size);
return 0;
}
static void mmap_read(struct perf_mmap *md)
{
unsigned int head = perf_mmap__read_head(md);
unsigned int old = md->prev;
unsigned char *data = md->base + page_size;
unsigned long size;
void *buf;
if (old == head)
return;
samples++;
size = head - old;
if ((old & md->mask) + size != (head & md->mask)) {
buf = &data[old & md->mask];
size = md->mask + 1 - (old & md->mask);
old += size;
write_output(buf, size);
}
buf = &data[old & md->mask];
size = head - old;
old += size;
write_output(buf, size);
md->prev = old;
perf_mmap__write_tail(md, old);
}
static volatile int done = 0;
static volatile int signr = -1;
static void sig_handler(int sig)
{
done = 1;
signr = sig;
}
static void sig_atexit(void)
{
if (child_pid > 0)
kill(child_pid, SIGTERM);
if (signr == -1 || signr == SIGUSR1)
return;
signal(signr, SIG_DFL);
kill(getpid(), signr);
}
static void config_attr(struct perf_evsel *evsel, struct perf_evlist *evlist)
{
struct perf_event_attr *attr = &evsel->attr;
int track = !evsel->idx; /* only the first counter needs these */
attr->inherit = !no_inherit;
attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
PERF_FORMAT_TOTAL_TIME_RUNNING |
PERF_FORMAT_ID;
attr->sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID;
if (evlist->nr_entries > 1)
attr->sample_type |= PERF_SAMPLE_ID;
/*
* We default some events to a 1 default interval. But keep
* it a weak assumption overridable by the user.
*/
if (!attr->sample_period || (user_freq != UINT_MAX &&
user_interval != ULLONG_MAX)) {
if (freq) {
attr->sample_type |= PERF_SAMPLE_PERIOD;
attr->freq = 1;
attr->sample_freq = freq;
} else {
attr->sample_period = default_interval;
}
}
if (no_samples)
attr->sample_freq = 0;
if (inherit_stat)
attr->inherit_stat = 1;
if (sample_address) {
attr->sample_type |= PERF_SAMPLE_ADDR;
attr->mmap_data = track;
}
if (call_graph)
attr->sample_type |= PERF_SAMPLE_CALLCHAIN;
if (system_wide)
attr->sample_type |= PERF_SAMPLE_CPU;
if (sample_id_all_avail &&
(sample_time || system_wide || !no_inherit || cpu_list))
attr->sample_type |= PERF_SAMPLE_TIME;
if (raw_samples) {
attr->sample_type |= PERF_SAMPLE_TIME;
attr->sample_type |= PERF_SAMPLE_RAW;
attr->sample_type |= PERF_SAMPLE_CPU;
}
if (nodelay) {
attr->watermark = 0;
attr->wakeup_events = 1;
}
attr->mmap = track;
attr->comm = track;
if (target_pid == -1 && target_tid == -1 && !system_wide) {
attr->disabled = 1;
attr->enable_on_exec = 1;
}
}
static bool perf_evlist__equal(struct perf_evlist *evlist,
struct perf_evlist *other)
{
struct perf_evsel *pos, *pair;
if (evlist->nr_entries != other->nr_entries)
return false;
pair = list_entry(other->entries.next, struct perf_evsel, node);
list_for_each_entry(pos, &evlist->entries, node) {
if (memcmp(&pos->attr, &pair->attr, sizeof(pos->attr) != 0))
return false;
pair = list_entry(pair->node.next, struct perf_evsel, node);
}
return true;
}
static void open_counters(struct perf_evlist *evlist)
{
struct perf_evsel *pos;
if (evlist->cpus->map[0] < 0)
no_inherit = true;
list_for_each_entry(pos, &evlist->entries, node) {
struct perf_event_attr *attr = &pos->attr;
/*
* Check if parse_single_tracepoint_event has already asked for
* PERF_SAMPLE_TIME.
*
* XXX this is kludgy but short term fix for problems introduced by
* eac23d1c that broke 'perf script' by having different sample_types
* when using multiple tracepoint events when we use a perf binary
* that tries to use sample_id_all on an older kernel.
*
* We need to move counter creation to perf_session, support
* different sample_types, etc.
*/
bool time_needed = attr->sample_type & PERF_SAMPLE_TIME;
config_attr(pos, evlist);
retry_sample_id:
attr->sample_id_all = sample_id_all_avail ? 1 : 0;
try_again:
if (perf_evsel__open(pos, evlist->cpus, evlist->threads, group) < 0) {
int err = errno;
if (err == EPERM || err == EACCES) {
ui__warning_paranoid();
exit(EXIT_FAILURE);
} else if (err == ENODEV && cpu_list) {
die("No such device - did you specify"
" an out-of-range profile CPU?\n");
} else if (err == EINVAL && sample_id_all_avail) {
/*
* Old kernel, no attr->sample_id_type_all field
*/
sample_id_all_avail = false;
if (!sample_time && !raw_samples && !time_needed)
attr->sample_type &= ~PERF_SAMPLE_TIME;
goto retry_sample_id;
}
/*
* If it's cycles then fall back to hrtimer
* based cpu-clock-tick sw counter, which
* is always available even if no PMU support:
*/
if (attr->type == PERF_TYPE_HARDWARE
&& attr->config == PERF_COUNT_HW_CPU_CYCLES) {
if (verbose)
ui__warning("The cycles event is not supported, "
"trying to fall back to cpu-clock-ticks\n");
attr->type = PERF_TYPE_SOFTWARE;
attr->config = PERF_COUNT_SW_CPU_CLOCK;
goto try_again;
}
if (err == ENOENT) {
ui__warning("The %s event is not supported.\n",
event_name(pos));
exit(EXIT_FAILURE);
}
printf("\n");
error("sys_perf_event_open() syscall returned with %d (%s). /bin/dmesg may provide additional information.\n",
err, strerror(err));
#if defined(__i386__) || defined(__x86_64__)
if (attr->type == PERF_TYPE_HARDWARE && err == EOPNOTSUPP)
die("No hardware sampling interrupt available."
" No APIC? If so then you can boot the kernel"
" with the \"lapic\" boot parameter to"
" force-enable it.\n");
#endif
die("No CONFIG_PERF_EVENTS=y kernel support configured?\n");
}
}
if (perf_evlist__set_filters(evlist)) {
error("failed to set filter with %d (%s)\n", errno,
strerror(errno));
exit(-1);
}
if (perf_evlist__mmap(evlist, mmap_pages, false) < 0)
die("failed to mmap with %d (%s)\n", errno, strerror(errno));
if (file_new)
session->evlist = evlist;
else {
if (!perf_evlist__equal(session->evlist, evlist)) {
fprintf(stderr, "incompatible append\n");
exit(-1);
}
}
perf_session__update_sample_type(session);
}
static int process_buildids(void)
{
u64 size = lseek(output, 0, SEEK_CUR);
if (size == 0)
return 0;
session->fd = output;
return __perf_session__process_events(session, post_processing_offset,
size - post_processing_offset,
size, &build_id__mark_dso_hit_ops);
}
static void atexit_header(void)
{
if (!pipe_output) {
session->header.data_size += bytes_written;
if (!no_buildid)
process_buildids();
perf_session__write_header(session, evsel_list, output, true);
perf_session__delete(session);
perf_evlist__delete(evsel_list);
symbol__exit();
}
}
static void perf_event__synthesize_guest_os(struct machine *machine, void *data)
{
int err;
struct perf_session *psession = data;
if (machine__is_host(machine))
return;
/*
*As for guest kernel when processing subcommand record&report,
*we arrange module mmap prior to guest kernel mmap and trigger
*a preload dso because default guest module symbols are loaded
*from guest kallsyms instead of /lib/modules/XXX/XXX. This
*method is used to avoid symbol missing when the first addr is
*in module instead of in guest kernel.
*/
err = perf_event__synthesize_modules(process_synthesized_event,
psession, machine);
if (err < 0)
pr_err("Couldn't record guest kernel [%d]'s reference"
" relocation symbol.\n", machine->pid);
/*
* We use _stext for guest kernel because guest kernel's /proc/kallsyms
* have no _text sometimes.
*/
err = perf_event__synthesize_kernel_mmap(process_synthesized_event,
psession, machine, "_text");
if (err < 0)
err = perf_event__synthesize_kernel_mmap(process_synthesized_event,
psession, machine,
"_stext");
if (err < 0)
pr_err("Couldn't record guest kernel [%d]'s reference"
" relocation symbol.\n", machine->pid);
}
static struct perf_event_header finished_round_event = {
.size = sizeof(struct perf_event_header),
.type = PERF_RECORD_FINISHED_ROUND,
};
static void mmap_read_all(void)
{
int i;
for (i = 0; i < evsel_list->nr_mmaps; i++) {
if (evsel_list->mmap[i].base)
mmap_read(&evsel_list->mmap[i]);
}
if (perf_header__has_feat(&session->header, HEADER_TRACE_INFO))
write_output(&finished_round_event, sizeof(finished_round_event));
}
static int __cmd_record(int argc, const char **argv)
{
int i;
struct stat st;
int flags;
int err;
unsigned long waking = 0;
int child_ready_pipe[2], go_pipe[2];
const bool forks = argc > 0;
char buf;
struct machine *machine;
page_size = sysconf(_SC_PAGE_SIZE);
atexit(sig_atexit);
signal(SIGCHLD, sig_handler);
signal(SIGINT, sig_handler);
signal(SIGUSR1, sig_handler);
if (forks && (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0)) {
perror("failed to create pipes");
exit(-1);
}
if (!output_name) {
if (!fstat(STDOUT_FILENO, &st) && S_ISFIFO(st.st_mode))
pipe_output = 1;
else
output_name = "perf.data";
}
if (output_name) {
if (!strcmp(output_name, "-"))
pipe_output = 1;
else if (!stat(output_name, &st) && st.st_size) {
if (write_mode == WRITE_FORCE) {
char oldname[PATH_MAX];
snprintf(oldname, sizeof(oldname), "%s.old",
output_name);
unlink(oldname);
rename(output_name, oldname);
}
} else if (write_mode == WRITE_APPEND) {
write_mode = WRITE_FORCE;
}
}
flags = O_CREAT|O_RDWR;
if (write_mode == WRITE_APPEND)
file_new = 0;
else
flags |= O_TRUNC;
if (pipe_output)
output = STDOUT_FILENO;
else
output = open(output_name, flags, S_IRUSR | S_IWUSR);
if (output < 0) {
perror("failed to create output file");
exit(-1);
}
session = perf_session__new(output_name, O_WRONLY,
write_mode == WRITE_FORCE, false, NULL);
if (session == NULL) {
pr_err("Not enough memory for reading perf file header\n");
return -1;
}
if (!no_buildid)
perf_header__set_feat(&session->header, HEADER_BUILD_ID);
if (!file_new) {
err = perf_session__read_header(session, output);
if (err < 0)
goto out_delete_session;
}
if (have_tracepoints(&evsel_list->entries))
perf_header__set_feat(&session->header, HEADER_TRACE_INFO);
/* 512 kiB: default amount of unprivileged mlocked memory */
if (mmap_pages == UINT_MAX)
mmap_pages = (512 * 1024) / page_size;
if (forks) {
child_pid = fork();
if (child_pid < 0) {
perror("failed to fork");
exit(-1);
}
if (!child_pid) {
if (pipe_output)
dup2(2, 1);
close(child_ready_pipe[0]);
close(go_pipe[1]);
fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
/*
* Do a dummy execvp to get the PLT entry resolved,
* so we avoid the resolver overhead on the real
* execvp call.
*/
execvp("", (char **)argv);
/*
* Tell the parent we're ready to go
*/
close(child_ready_pipe[1]);
/*
* Wait until the parent tells us to go.
*/
if (read(go_pipe[0], &buf, 1) == -1)
perror("unable to read pipe");
execvp(argv[0], (char **)argv);
perror(argv[0]);
kill(getppid(), SIGUSR1);
exit(-1);
}
if (!system_wide && target_tid == -1 && target_pid == -1)
evsel_list->threads->map[0] = child_pid;
close(child_ready_pipe[1]);
close(go_pipe[0]);
/*
* wait for child to settle
*/
if (read(child_ready_pipe[0], &buf, 1) == -1) {
perror("unable to read pipe");
exit(-1);
}
close(child_ready_pipe[0]);
}
open_counters(evsel_list);
/*
* perf_session__delete(session) will be called at atexit_header()
*/
atexit(atexit_header);
if (pipe_output) {
err = perf_header__write_pipe(output);
if (err < 0)
return err;
} else if (file_new) {
err = perf_session__write_header(session, evsel_list,
output, false);
if (err < 0)
return err;
}
post_processing_offset = lseek(output, 0, SEEK_CUR);
if (pipe_output) {
err = perf_session__synthesize_attrs(session,
process_synthesized_event);
if (err < 0) {
pr_err("Couldn't synthesize attrs.\n");
return err;
}
err = perf_event__synthesize_event_types(process_synthesized_event,
session);
if (err < 0) {
pr_err("Couldn't synthesize event_types.\n");
return err;
}
if (have_tracepoints(&evsel_list->entries)) {
/*
* FIXME err <= 0 here actually means that
* there were no tracepoints so its not really
* an error, just that we don't need to
* synthesize anything. We really have to
* return this more properly and also
* propagate errors that now are calling die()
*/
err = perf_event__synthesize_tracing_data(output, evsel_list,
process_synthesized_event,
session);
if (err <= 0) {
pr_err("Couldn't record tracing data.\n");
return err;
}
advance_output(err);
}
}
machine = perf_session__find_host_machine(session);
if (!machine) {
pr_err("Couldn't find native kernel information.\n");
return -1;
}
err = perf_event__synthesize_kernel_mmap(process_synthesized_event,
session, machine, "_text");
if (err < 0)
err = perf_event__synthesize_kernel_mmap(process_synthesized_event,
session, machine, "_stext");
if (err < 0)
pr_err("Couldn't record kernel reference relocation symbol\n"
"Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
"Check /proc/kallsyms permission or run as root.\n");
err = perf_event__synthesize_modules(process_synthesized_event,
session, machine);
if (err < 0)
pr_err("Couldn't record kernel module information.\n"
"Symbol resolution may be skewed if relocation was used (e.g. kexec).\n"
"Check /proc/modules permission or run as root.\n");
if (perf_guest)
perf_session__process_machines(session,
perf_event__synthesize_guest_os);
if (!system_wide)
perf_event__synthesize_thread_map(evsel_list->threads,
process_synthesized_event,
session);
else
perf_event__synthesize_threads(process_synthesized_event,
session);
if (realtime_prio) {
struct sched_param param;
param.sched_priority = realtime_prio;
if (sched_setscheduler(0, SCHED_FIFO, ¶m)) {
pr_err("Could not set realtime priority.\n");
exit(-1);
}
}
/*
* Let the child rip
*/
if (forks)
close(go_pipe[1]);
for (;;) {
int hits = samples;
int thread;
mmap_read_all();
if (hits == samples) {
if (done)
break;
err = poll(evsel_list->pollfd, evsel_list->nr_fds, -1);
waking++;
}
if (done) {
for (i = 0; i < evsel_list->cpus->nr; i++) {
struct perf_evsel *pos;
list_for_each_entry(pos, &evsel_list->entries, node) {
for (thread = 0;
thread < evsel_list->threads->nr;
thread++)
ioctl(FD(pos, i, thread),
PERF_EVENT_IOC_DISABLE);
}
}
}
}
if (quiet || signr == SIGUSR1)
return 0;
fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);
/*
* Approximate RIP event size: 24 bytes.
*/
fprintf(stderr,
"[ perf record: Captured and wrote %.3f MB %s (~%" PRIu64 " samples) ]\n",
(double)bytes_written / 1024.0 / 1024.0,
output_name,
bytes_written / 24);
return 0;
out_delete_session:
perf_session__delete(session);
return err;
}
static const char * const record_usage[] = {
"perf record [<options>] [<command>]",
"perf record [<options>] -- <command> [<options>]",
NULL
};
static bool force, append_file;
const struct option record_options[] = {
OPT_CALLBACK('e', "event", &evsel_list, "event",
"event selector. use 'perf list' to list available events",
parse_events),
OPT_CALLBACK(0, "filter", &evsel_list, "filter",
"event filter", parse_filter),
OPT_INTEGER('p', "pid", &target_pid,
"record events on existing process id"),
OPT_INTEGER('t', "tid", &target_tid,
"record events on existing thread id"),
OPT_INTEGER('r', "realtime", &realtime_prio,
"collect data with this RT SCHED_FIFO priority"),
OPT_BOOLEAN('D', "no-delay", &nodelay,
"collect data without buffering"),
OPT_BOOLEAN('R', "raw-samples", &raw_samples,
"collect raw sample records from all opened counters"),
OPT_BOOLEAN('a', "all-cpus", &system_wide,
"system-wide collection from all CPUs"),
OPT_BOOLEAN('A', "append", &append_file,
"append to the output file to do incremental profiling"),
OPT_STRING('C', "cpu", &cpu_list, "cpu",
"list of cpus to monitor"),
OPT_BOOLEAN('f', "force", &force,
"overwrite existing data file (deprecated)"),
OPT_U64('c', "count", &user_interval, "event period to sample"),
OPT_STRING('o', "output", &output_name, "file",
"output file name"),
OPT_BOOLEAN('i', "no-inherit", &no_inherit,
"child tasks do not inherit counters"),
OPT_UINTEGER('F', "freq", &user_freq, "profile at this frequency"),
OPT_UINTEGER('m', "mmap-pages", &mmap_pages, "number of mmap data pages"),
OPT_BOOLEAN('g', "call-graph", &call_graph,
"do call-graph (stack chain/backtrace) recording"),
OPT_INCR('v', "verbose", &verbose,
"be more verbose (show counter open errors, etc)"),
OPT_BOOLEAN('q', "quiet", &quiet, "don't print any message"),
OPT_BOOLEAN('s', "stat", &inherit_stat,
"per thread counts"),
OPT_BOOLEAN('d', "data", &sample_address,
"Sample addresses"),
OPT_BOOLEAN('T', "timestamp", &sample_time, "Sample timestamps"),
OPT_BOOLEAN('n', "no-samples", &no_samples,
"don't sample"),
OPT_BOOLEAN('N', "no-buildid-cache", &no_buildid_cache,
"do not update the buildid cache"),
OPT_BOOLEAN('B', "no-buildid", &no_buildid,
"do not collect buildids in perf.data"),
OPT_CALLBACK('G', "cgroup", &evsel_list, "name",
"monitor event in cgroup name only",
parse_cgroups),
OPT_END()
};
int cmd_record(int argc, const char **argv, const char *prefix __used)
{
int err = -ENOMEM;
struct perf_evsel *pos;
evsel_list = perf_evlist__new(NULL, NULL);
if (evsel_list == NULL)
return -ENOMEM;
argc = parse_options(argc, argv, record_options, record_usage,
PARSE_OPT_STOP_AT_NON_OPTION);
if (!argc && target_pid == -1 && target_tid == -1 &&
!system_wide && !cpu_list)
usage_with_options(record_usage, record_options);
if (force && append_file) {
fprintf(stderr, "Can't overwrite and append at the same time."
" You need to choose between -f and -A");
usage_with_options(record_usage, record_options);
} else if (append_file) {
write_mode = WRITE_APPEND;
} else {
write_mode = WRITE_FORCE;
}
if (nr_cgroups && !system_wide) {
fprintf(stderr, "cgroup monitoring only available in"
" system-wide mode\n");
usage_with_options(record_usage, record_options);
}
symbol__init();
if (no_buildid_cache || no_buildid)
disable_buildid_cache();
if (evsel_list->nr_entries == 0 &&
perf_evlist__add_default(evsel_list) < 0) {
pr_err("Not enough memory for event selector list\n");
goto out_symbol_exit;
}
if (target_pid != -1)
target_tid = target_pid;
if (perf_evlist__create_maps(evsel_list, target_pid,
target_tid, cpu_list) < 0)
usage_with_options(record_usage, record_options);
list_for_each_entry(pos, &evsel_list->entries, node) {
if (perf_evsel__alloc_fd(pos, evsel_list->cpus->nr,
evsel_list->threads->nr) < 0)
goto out_free_fd;
if (perf_header__push_event(pos->attr.config, event_name(pos)))
goto out_free_fd;
}
if (perf_evlist__alloc_pollfd(evsel_list) < 0)
goto out_free_fd;
if (user_interval != ULLONG_MAX)
default_interval = user_interval;
if (user_freq != UINT_MAX)
freq = user_freq;
/*
* User specified count overrides default frequency.
*/
if (default_interval)
freq = 0;
else if (freq) {
default_interval = freq;
} else {
fprintf(stderr, "frequency and count are zero, aborting\n");
err = -EINVAL;
goto out_free_fd;
}
err = __cmd_record(argc, argv);
out_free_fd:
perf_evlist__delete_maps(evsel_list);
out_symbol_exit:
symbol__exit();
return err;
}