static int perf_session__open(struct perf_session *self, bool force)
{
struct stat input_stat;
self->fd = open(self->filename, O_RDONLY);
if (self->fd < 0) {
pr_err("failed to open file: %s", self->filename);
if (!strcmp(self->filename, "perf.data"))
pr_err(" (try 'perf record' first)");
pr_err("\n");
return -errno;
}
if (fstat(self->fd, &input_stat) < 0)
goto out_close;
if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
pr_err("file %s not owned by current user or root\n",
self->filename);
goto out_close;
}
if (!input_stat.st_size) {
pr_info("zero-sized file (%s), nothing to do!\n",
self->filename);
goto out_close;
}
if (perf_header__read(&self->header, self->fd) < 0) {
pr_err("incompatible file format");
goto out_close;
}
self->size = input_stat.st_size;
return 0;
out_close:
close(self->fd);
self->fd = -1;
return -1;
}
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;
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 (!stat(output_name, &st) && st.st_size) {
if (!force && !append_file) {
fprintf(stderr, "Error, output file %s exists, use -A to append or -f to overwrite.\n",
output_name);
exit(-1);
}
} 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 (!system_wide) {
pid = target_pid;
if (pid == -1)
pid = getpid();
open_counters(profile_cpu, pid);
} else {
if (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)
event__synthesize_thread(pid, process_synthesized_event);
else
event__synthesize_threads(process_synthesized_event);
if (target_pid == -1 && argc) {
pid = fork();
if (pid < 0)
die("failed to fork");
if (!pid) {
if (execvp(argv[0], (char **)argv)) {
perror(argv[0]);
exit(-1);
}
} else {
/*
* Wait a bit for the execv'ed child to appear
* and be updated in /proc
* FIXME: Do you know a less heuristical solution?
*/
usleep(1000);
event__synthesize_thread(pid,
process_synthesized_event);
}
child_pid = pid;
}
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);
}
}
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 int __cmd_record(int argc, const char **argv)
{
int i, counter;
struct stat st;
pid_t pid = 0;
int flags;
int ret;
unsigned long waking = 0;
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 (!stat(output_name, &st) && st.st_size) {
if (!force && !append_file) {
fprintf(stderr, "Error, output file %s exists, use -A to append or -f to overwrite.\n",
output_name);
exit(-1);
}
} 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);
}
if (!file_new)
header = perf_header__read(output);
else
header = perf_header__new();
if (raw_samples) {
read_tracing_data(attrs, nr_counters);
} else {
for (i = 0; i < nr_counters; i++) {
if (attrs[i].sample_type & PERF_SAMPLE_RAW) {
read_tracing_data(attrs, nr_counters);
break;
}
}
}
atexit(atexit_header);
if (!system_wide) {
pid = target_pid;
if (pid == -1)
pid = getpid();
open_counters(profile_cpu, pid);
} else {
if (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)
perf_header__write(header, output);
if (!system_wide) {
pid_t tgid = pid_synthesize_comm_event(pid, 0);
pid_synthesize_mmap_samples(pid, tgid);
} else
synthesize_all();
if (target_pid == -1 && argc) {
pid = fork();
if (pid < 0)
perror("failed to fork");
if (!pid) {
if (execvp(argv[0], (char **)argv)) {
perror(argv[0]);
exit(-1);
}
}
child_pid = pid;
}
if (realtime_prio) {
struct sched_param param;
param.sched_priority = realtime_prio;
if (sched_setscheduler(0, SCHED_FIFO, ¶m)) {
printf("Could not set realtime priority.\n");
exit(-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;
ret = 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 int __cmd_trace(void)
{
int ret, rc = EXIT_FAILURE;
unsigned long offset = 0;
unsigned long head = 0;
struct stat perf_stat;
event_t *event;
uint32_t size;
char *buf;
trace_report();
register_idle_thread(&threads, &last_match);
input = open(input_name, O_RDONLY);
if (input < 0) {
perror("failed to open file");
exit(-1);
}
ret = fstat(input, &perf_stat);
if (ret < 0) {
perror("failed to stat file");
exit(-1);
}
if (!perf_stat.st_size) {
fprintf(stderr, "zero-sized file, nothing to do!\n");
exit(0);
}
header = perf_header__read(input);
head = header->data_offset;
sample_type = perf_header__sample_type(header);
if (!(sample_type & PERF_SAMPLE_RAW))
die("No trace sample to read. Did you call perf record "
"without -R?");
if (load_kernel() < 0) {
perror("failed to load kernel symbols");
return EXIT_FAILURE;
}
remap:
buf = (char *)mmap(NULL, page_size * mmap_window, PROT_READ,
MAP_SHARED, input, offset);
if (buf == MAP_FAILED) {
perror("failed to mmap file");
exit(-1);
}
more:
event = (event_t *)(buf + head);
if (head + event->header.size >= page_size * mmap_window) {
unsigned long shift = page_size * (head / page_size);
int res;
res = munmap(buf, page_size * mmap_window);
assert(res == 0);
offset += shift;
head -= shift;
goto remap;
}
size = event->header.size;
if (!size || process_event(event, offset, head) < 0) {
/*
* assume we lost track of the stream, check alignment, and
* increment a single u64 in the hope to catch on again 'soon'.
*/
if (unlikely(head & 7))
head &= ~7ULL;
size = 8;
}
head += size;
if (offset + head < (unsigned long)perf_stat.st_size)
goto more;
rc = EXIT_SUCCESS;
close(input);
return rc;
}
