Linux-2.6.33.2/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.
*/
#include "builtin.h"
#include "perf.h"
#include "util/util.h"
#include "util/parse-options.h"
#include "util/parse-events.h"
#include "util/string.h"
#include "util/header.h"
#include "util/event.h"
#include "util/debug.h"
#include "util/session.h"
#include "util/symbol.h"
#include <unistd.h>
#include <sched.h>
static int fd[MAX_NR_CPUS][MAX_COUNTERS];
static long default_interval = 0;
static int nr_cpus = 0;
static unsigned int page_size;
static unsigned int mmap_pages = 128;
static int freq = 1000;
static int output;
static const char *output_name = "perf.data";
static int group = 0;
static unsigned int realtime_prio = 0;
static int raw_samples = 0;
static int system_wide = 0;
static int profile_cpu = -1;
static pid_t target_pid = -1;
static pid_t child_pid = -1;
static int inherit = 1;
static int force = 0;
static int append_file = 0;
static int call_graph = 0;
static int inherit_stat = 0;
static int no_samples = 0;
static int sample_address = 0;
static int multiplex = 0;
static int multiplex_fd = -1;
static long samples = 0;
static struct timeval last_read;
static struct timeval this_read;
static u64 bytes_written = 0;
static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
static int nr_poll = 0;
static int nr_cpu = 0;
static int file_new = 1;
static struct perf_session *session;
struct mmap_data {
int counter;
void *base;
unsigned int mask;
unsigned int prev;
};
static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
static unsigned long mmap_read_head(struct mmap_data *md)
{
struct perf_event_mmap_page *pc = md->base;
long head;
head = pc->data_head;
rmb();
return head;
}
static void mmap_write_tail(struct mmap_data *md, unsigned long tail)
{
struct perf_event_mmap_page *pc = md->base;
/*
* ensure all reads are done before we write the tail out.
*/
/* mb(); */
pc->data_tail = tail;
}
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 void write_event(event_t *buf, size_t size)
{
/*
* Add it to the list of DSOs, so that when we finish this
* record session we can pick the available build-ids.
*/
if (buf->header.type == PERF_RECORD_MMAP)
dsos__findnew(buf->mmap.filename);
write_output(buf, size);
}
static int process_synthesized_event(event_t *event,
struct perf_session *self __used)
{
write_event(event, event->header.size);
return 0;
}
static void mmap_read(struct mmap_data *md)
{
unsigned int head = mmap_read_head(md);
unsigned int old = md->prev;
unsigned char *data = md->base + page_size;
unsigned long size;
void *buf;
int diff;
gettimeofday(&this_read, NULL);
/*
* If we're further behind than half the buffer, there's a chance
* the writer will bite our tail and mess up the samples under us.
*
* If we somehow ended up ahead of the head, we got messed up.
*
* In either case, truncate and restart at head.
*/
diff = head - old;
if (diff < 0) {
struct timeval iv;
unsigned long msecs;
timersub(&this_read, &last_read, &iv);
msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
fprintf(stderr, "WARNING: failed to keep up with mmap data."
" Last read %lu msecs ago.\n", msecs);
/*
* head points to a known good entry, start there.
*/
old = head;
}
last_read = this_read;
if (old != head)
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_event(buf, size);
}
buf = &data[old & md->mask];
size = head - old;
old += size;
write_event(buf, size);
md->prev = old;
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 != -1)
kill(child_pid, SIGTERM);
if (signr == -1)
return;
signal(signr, SIG_DFL);
kill(getpid(), signr);
}
static int group_fd;
static struct perf_header_attr *get_header_attr(struct perf_event_attr *a, int nr)
{
struct perf_header_attr *h_attr;
if (nr < session->header.attrs) {
h_attr = session->header.attr[nr];
} else {
h_attr = perf_header_attr__new(a);
if (h_attr != NULL)
if (perf_header__add_attr(&session->header, h_attr) < 0) {
perf_header_attr__delete(h_attr);
h_attr = NULL;
}
}
return h_attr;
}
static void create_counter(int counter, int cpu, pid_t pid)
{
char *filter = filters[counter];
struct perf_event_attr *attr = attrs + counter;
struct perf_header_attr *h_attr;
int track = !counter; /* only the first counter needs these */
int ret;
struct {
u64 count;
u64 time_enabled;
u64 time_running;
u64 id;
} read_data;
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 (freq) {
attr->sample_type |= PERF_SAMPLE_PERIOD;
attr->freq = 1;
attr->sample_freq = freq;
}
if (no_samples)
attr->sample_freq = 0;
if (inherit_stat)
attr->inherit_stat = 1;
if (sample_address)
attr->sample_type |= PERF_SAMPLE_ADDR;
if (call_graph)
attr->sample_type |= PERF_SAMPLE_CALLCHAIN;
if (raw_samples) {
attr->sample_type |= PERF_SAMPLE_TIME;
attr->sample_type |= PERF_SAMPLE_RAW;
attr->sample_type |= PERF_SAMPLE_CPU;
}
attr->mmap = track;
attr->comm = track;
attr->inherit = inherit;
attr->disabled = 1;
try_again:
fd[nr_cpu][counter] = sys_perf_event_open(attr, pid, cpu, group_fd, 0);
if (fd[nr_cpu][counter] < 0) {
int err = errno;
if (err == EPERM || err == EACCES)
die("Permission error - are you root?\n");
else if (err == ENODEV && profile_cpu != -1)
die("No such device - did you specify an out-of-range profile CPU?\n");
/*
* 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)
warning(" ... trying to fall back to cpu-clock-ticks\n");
attr->type = PERF_TYPE_SOFTWARE;
attr->config = PERF_COUNT_SW_CPU_CLOCK;
goto try_again;
}
printf("\n");
error("perfcounter syscall returned with %d (%s)\n",
fd[nr_cpu][counter], 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");
exit(-1);
}
h_attr = get_header_attr(attr, counter);
if (h_attr == NULL)
die("nomem\n");
if (!file_new) {
if (memcmp(&h_attr->attr, attr, sizeof(*attr))) {
fprintf(stderr, "incompatible append\n");
exit(-1);
}
}
if (read(fd[nr_cpu][counter], &read_data, sizeof(read_data)) == -1) {
perror("Unable to read perf file descriptor\n");
exit(-1);
}
if (perf_header_attr__add_id(h_attr, read_data.id) < 0) {
pr_warning("Not enough memory to add id\n");
exit(-1);
}
assert(fd[nr_cpu][counter] >= 0);
fcntl(fd[nr_cpu][counter], F_SETFL, O_NONBLOCK);
/*
* First counter acts as the group leader:
*/
if (group && group_fd == -1)
group_fd = fd[nr_cpu][counter];
if (multiplex && multiplex_fd == -1)
multiplex_fd = fd[nr_cpu][counter];
if (multiplex && fd[nr_cpu][counter] != multiplex_fd) {
ret = ioctl(fd[nr_cpu][counter], PERF_EVENT_IOC_SET_OUTPUT, multiplex_fd);
assert(ret != -1);
} else {
event_array[nr_poll].fd = fd[nr_cpu][counter];
event_array[nr_poll].events = POLLIN;
nr_poll++;
mmap_array[nr_cpu][counter].counter = counter;
mmap_array[nr_cpu][counter].prev = 0;
mmap_array[nr_cpu][counter].mask = mmap_pages*page_size - 1;
mmap_array[nr_cpu][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
PROT_READ|PROT_WRITE, MAP_SHARED, fd[nr_cpu][counter], 0);
if (mmap_array[nr_cpu][counter].base == MAP_FAILED) {
error("failed to mmap with %d (%s)\n", errno, strerror(errno));
exit(-1);
}
}
if (filter != NULL) {
ret = ioctl(fd[nr_cpu][counter],
PERF_EVENT_IOC_SET_FILTER, filter);
if (ret) {
error("failed to set filter with %d (%s)\n", errno,
strerror(errno));
exit(-1);
}
}
ioctl(fd[nr_cpu][counter], PERF_EVENT_IOC_ENABLE);
}
static void open_counters(int cpu, pid_t pid)
{
int counter;
group_fd = -1;
for (counter = 0; counter < nr_counters; counter++)
create_counter(counter, cpu, pid);
nr_cpu++;
}
static void atexit_header(void)
{
session->header.data_size += bytes_written;
perf_header__write(&session->header, output, true);
}
static int __cmd_record(int argc, const char **argv)
{
int i, counter;
struct stat st;
pid_t pid = 0;
int flags;
int err;
unsigned long waking = 0;
int child_ready_pipe[2], go_pipe[2];
const bool forks = target_pid == -1 && argc > 0;
char buf;
page_size = sysconf(_SC_PAGE_SIZE);
nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
assert(nr_cpus <= MAX_NR_CPUS);
assert(nr_cpus >= 0);
atexit(sig_atexit);
signal(SIGCHLD, sig_handler);
signal(SIGINT, sig_handler);
if (forks && (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0)) {
perror("failed to create pipes");
exit(-1);
}
if (!stat(output_name, &st) && st.st_size) {
if (!force) {
if (!append_file) {
pr_err("Error, output file %s exists, use -A "
"to append or -f to overwrite.\n",
output_name);
exit(-1);
}
} else {
char oldname[PATH_MAX];
snprintf(oldname, sizeof(oldname), "%s.old",
output_name);
unlink(oldname);
rename(output_name, oldname);
}
} else {
append_file = 0;
}
flags = O_CREAT|O_RDWR;
if (append_file)
file_new = 0;
else
flags |= O_TRUNC;
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, force);
if (session == NULL) {
pr_err("Not enough memory for reading perf file header\n");
return -1;
}
if (!file_new) {
err = perf_header__read(&session->header, output);
if (err < 0)
return err;
}
if (raw_samples) {
perf_header__set_feat(&session->header, HEADER_TRACE_INFO);
} else {
for (i = 0; i < nr_counters; i++) {
if (attrs[i].sample_type & PERF_SAMPLE_RAW) {
perf_header__set_feat(&session->header, HEADER_TRACE_INFO);
break;
}
}
}
atexit(atexit_header);
if (forks) {
pid = fork();
if (pid < 0) {
perror("failed to fork");
exit(-1);
}
if (!pid) {
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]);
exit(-1);
}
child_pid = pid;
if (!system_wide)
target_pid = 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]);
}
if ((!system_wide && !inherit) || profile_cpu != -1) {
open_counters(profile_cpu, target_pid);
} else {
for (i = 0; i < nr_cpus; i++)
open_counters(i, target_pid);
}
if (file_new) {
err = perf_header__write(&session->header, output, false);
if (err < 0)
return err;
}
if (!system_wide && profile_cpu == -1)
event__synthesize_thread(pid, process_synthesized_event,
session);
else
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;
for (i = 0; i < nr_cpu; i++) {
for (counter = 0; counter < nr_counters; counter++) {
if (mmap_array[i][counter].base)
mmap_read(&mmap_array[i][counter]);
}
}
if (hits == samples) {
if (done)
break;
err = poll(event_array, nr_poll, -1);
waking++;
}
if (done) {
for (i = 0; i < nr_cpu; i++) {
for (counter = 0; counter < nr_counters; counter++)
ioctl(fd[i][counter], PERF_EVENT_IOC_DISABLE);
}
}
}
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 (~%lld samples) ]\n",
(double)bytes_written / 1024.0 / 1024.0,
output_name,
bytes_written / 24);
return 0;
}
static const char * const record_usage[] = {
"perf record [<options>] [<command>]",
"perf record [<options>] -- <command> [<options>]",
NULL
};
static const struct option options[] = {
OPT_CALLBACK('e', "event", NULL, "event",
"event selector. use 'perf list' to list available events",
parse_events),
OPT_CALLBACK(0, "filter", NULL, "filter",
"event filter", parse_filter),
OPT_INTEGER('p', "pid", &target_pid,
"record events on existing pid"),
OPT_INTEGER('r', "realtime", &realtime_prio,
"collect data with this RT SCHED_FIFO priority"),
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_INTEGER('C', "profile_cpu", &profile_cpu,
"CPU to profile on"),
OPT_BOOLEAN('f', "force", &force,
"overwrite existing data file"),
OPT_LONG('c', "count", &default_interval,
"event period to sample"),
OPT_STRING('o', "output", &output_name, "file",
"output file name"),
OPT_BOOLEAN('i', "inherit", &inherit,
"child tasks inherit counters"),
OPT_INTEGER('F', "freq", &freq,
"profile at this frequency"),
OPT_INTEGER('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_BOOLEAN('v', "verbose", &verbose,
"be more verbose (show counter open errors, etc)"),
OPT_BOOLEAN('s', "stat", &inherit_stat,
"per thread counts"),
OPT_BOOLEAN('d', "data", &sample_address,
"Sample addresses"),
OPT_BOOLEAN('n', "no-samples", &no_samples,
"don't sample"),
OPT_BOOLEAN('M', "multiplex", &multiplex,
"multiplex counter output in a single channel"),
OPT_END()
};
int cmd_record(int argc, const char **argv, const char *prefix __used)
{
int counter;
argc = parse_options(argc, argv, options, record_usage,
PARSE_OPT_STOP_AT_NON_OPTION);
if (!argc && target_pid == -1 && !system_wide && profile_cpu == -1)
usage_with_options(record_usage, options);
symbol__init();
if (!nr_counters) {
nr_counters = 1;
attrs[0].type = PERF_TYPE_HARDWARE;
attrs[0].config = PERF_COUNT_HW_CPU_CYCLES;
}
/*
* 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");
exit(EXIT_FAILURE);
}
for (counter = 0; counter < nr_counters; counter++) {
if (attrs[counter].sample_period)
continue;
attrs[counter].sample_period = default_interval;
}
return __cmd_record(argc, argv);
}