int perf_event_paranoid(void)
{
int value;
if (sysctl__read_int("kernel/perf_event_paranoid", &value))
return INT_MAX;
return value;
}
/*
* Check whether we can use a group for top down.
* Without a group may get bad results due to multiplexing.
*/
bool arch_topdown_check_group(bool *warn)
{
int n;
if (sysctl__read_int("kernel/nmi_watchdog", &n) < 0)
return false;
if (n > 0) {
*warn = true;
return false;
}
return true;
}
static struct task_desc *register_pid(struct perf_sched *sched,
unsigned long pid, const char *comm)
{
struct task_desc *task;
static int pid_max;
if (sched->pid_to_task == NULL) {
if (sysctl__read_int("kernel/pid_max", &pid_max) < 0)
pid_max = MAX_PID;
BUG_ON((sched->pid_to_task = calloc(pid_max, sizeof(struct task_desc *))) == NULL);
}
if (pid >= (unsigned long)pid_max) {
BUG_ON((sched->pid_to_task = realloc(sched->pid_to_task, (pid + 1) *
sizeof(struct task_desc *))) == NULL);
while (pid >= (unsigned long)pid_max)
sched->pid_to_task[pid_max++] = NULL;
}
task = sched->pid_to_task[pid];
if (task)
return task;
task = zalloc(sizeof(*task));
task->pid = pid;
task->nr = sched->nr_tasks;
strcpy(task->comm, comm);
/*
* every task starts in sleeping state - this gets ignored
* if there's no wakeup pointing to this sleep state:
*/
add_sched_event_sleep(sched, task, 0, 0);
sched->pid_to_task[pid] = task;
sched->nr_tasks++;
sched->tasks = realloc(sched->tasks, sched->nr_tasks * sizeof(struct task_desc *));
BUG_ON(!sched->tasks);
sched->tasks[task->nr] = task;
if (verbose)
printf("registered task #%ld, PID %ld (%s)\n", sched->nr_tasks, pid, comm);
return task;
}
int main(int argc, const char **argv)
{
int err;
const char *cmd;
char sbuf[STRERR_BUFSIZE];
int value;
/* libsubcmd init */
exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT);
pager_init(PERF_PAGER_ENVIRONMENT);
/* The page_size is placed in util object. */
page_size = sysconf(_SC_PAGE_SIZE);
cache_line_size(&cacheline_size);
if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0)
sysctl_perf_event_max_stack = value;
if (sysctl__read_int("kernel/perf_event_max_contexts_per_stack", &value) == 0)
sysctl_perf_event_max_contexts_per_stack = value;
cmd = extract_argv0_path(argv[0]);
if (!cmd)
cmd = "perf-help";
srandom(time(NULL));
perf_config__init();
err = perf_config(perf_default_config, NULL);
if (err)
return err;
set_buildid_dir(NULL);
/* get debugfs/tracefs mount point from /proc/mounts */
tracing_path_mount();
/*
* "perf-xxxx" is the same as "perf xxxx", but we obviously:
*
* - cannot take flags in between the "perf" and the "xxxx".
* - cannot execute it externally (since it would just do
* the same thing over again)
*
* So we just directly call the internal command handler. If that one
* fails to handle this, then maybe we just run a renamed perf binary
* that contains a dash in its name. To handle this scenario, we just
* fall through and ignore the "xxxx" part of the command string.
*/
if (strstarts(cmd, "perf-")) {
cmd += 5;
argv[0] = cmd;
handle_internal_command(argc, argv);
/*
* If the command is handled, the above function does not
* return undo changes and fall through in such a case.
*/
cmd -= 5;
argv[0] = cmd;
}
if (strstarts(cmd, "trace")) {
#if defined(HAVE_LIBAUDIT_SUPPORT) || defined(HAVE_SYSCALL_TABLE_SUPPORT)
setup_path();
argv[0] = "trace";
return cmd_trace(argc, argv);
#else
fprintf(stderr,
"trace command not available: missing audit-libs devel package at build time.\n");
goto out;
#endif
}
/* Look for flags.. */
argv++;
argc--;
handle_options(&argv, &argc, NULL);
commit_pager_choice();
if (argc > 0) {
if (strstarts(argv[0], "--"))
argv[0] += 2;
} else {
/* The user didn't specify a command; give them help */
printf("\n usage: %s\n\n", perf_usage_string);
list_common_cmds_help();
printf("\n %s\n\n", perf_more_info_string);
goto out;
}
cmd = argv[0];
test_attr__init();
/*
* We use PATH to find perf commands, but we prepend some higher
* precedence paths: the "--exec-path" option, the PERF_EXEC_PATH
* environment, and the $(perfexecdir) from the Makefile at build
* time.
*/
setup_path();
/*
* Block SIGWINCH notifications so that the thread that wants it can
* unblock and get syscalls like select interrupted instead of waiting
* forever while the signal goes to some other non interested thread.
*/
pthread__block_sigwinch();
perf_debug_setup();
while (1) {
static int done_help;
run_argv(&argc, &argv);
if (errno != ENOENT)
break;
if (!done_help) {
cmd = argv[0] = help_unknown_cmd(cmd);
done_help = 1;
} else
break;
}
fprintf(stderr, "Failed to run command '%s': %s\n",
cmd, str_error_r(errno, sbuf, sizeof(sbuf)));
out:
return 1;
}
