linux/tools/perf/perf.c

480 lines
11 KiB
C

/*
* perf.c
*
* Performance analysis utility.
*
* This is the main hub from which the sub-commands (perf stat,
* perf top, perf record, perf report, etc.) are started.
*/
#include "builtin.h"
#include "util/exec_cmd.h"
#include "util/cache.h"
#include "util/quote.h"
#include "util/run-command.h"
#include "util/parse-events.h"
#include "util/string.h"
#include "util/debugfs.h"
const char perf_usage_string[] =
"perf [--version] [--help] COMMAND [ARGS]";
const char perf_more_info_string[] =
"See 'perf help COMMAND' for more information on a specific command.";
static int use_pager = -1;
struct pager_config {
const char *cmd;
int val;
};
static char debugfs_mntpt[MAXPATHLEN];
static int pager_command_config(const char *var, const char *value, void *data)
{
struct pager_config *c = data;
if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
c->val = perf_config_bool(var, value);
return 0;
}
/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
int check_pager_config(const char *cmd)
{
struct pager_config c;
c.cmd = cmd;
c.val = -1;
perf_config(pager_command_config, &c);
return c.val;
}
static void commit_pager_choice(void)
{
switch (use_pager) {
case 0:
setenv("PERF_PAGER", "cat", 1);
break;
case 1:
/* setup_pager(); */
break;
default:
break;
}
}
static void set_debugfs_path(void)
{
char *path;
path = getenv(PERF_DEBUGFS_ENVIRONMENT);
snprintf(debugfs_path, MAXPATHLEN, "%s/%s", path ?: debugfs_mntpt,
"tracing/events");
}
static int handle_options(const char ***argv, int *argc, int *envchanged)
{
int handled = 0;
while (*argc > 0) {
const char *cmd = (*argv)[0];
if (cmd[0] != '-')
break;
/*
* For legacy reasons, the "version" and "help"
* commands can be written with "--" prepended
* to make them look like flags.
*/
if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
break;
/*
* Check remaining flags.
*/
if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
cmd += strlen(CMD_EXEC_PATH);
if (*cmd == '=')
perf_set_argv_exec_path(cmd + 1);
else {
puts(perf_exec_path());
exit(0);
}
} else if (!strcmp(cmd, "--html-path")) {
puts(system_path(PERF_HTML_PATH));
exit(0);
} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
use_pager = 1;
} else if (!strcmp(cmd, "--no-pager")) {
use_pager = 0;
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--perf-dir")) {
if (*argc < 2) {
fprintf(stderr, "No directory given for --perf-dir.\n");
usage(perf_usage_string);
}
setenv(PERF_DIR_ENVIRONMENT, (*argv)[1], 1);
if (envchanged)
*envchanged = 1;
(*argv)++;
(*argc)--;
handled++;
} else if (!prefixcmp(cmd, CMD_PERF_DIR)) {
setenv(PERF_DIR_ENVIRONMENT, cmd + strlen(CMD_PERF_DIR), 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--work-tree")) {
if (*argc < 2) {
fprintf(stderr, "No directory given for --work-tree.\n");
usage(perf_usage_string);
}
setenv(PERF_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
if (envchanged)
*envchanged = 1;
(*argv)++;
(*argc)--;
} else if (!prefixcmp(cmd, CMD_WORK_TREE)) {
setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + strlen(CMD_WORK_TREE), 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--debugfs-dir")) {
if (*argc < 2) {
fprintf(stderr, "No directory given for --debugfs-dir.\n");
usage(perf_usage_string);
}
strncpy(debugfs_mntpt, (*argv)[1], MAXPATHLEN);
debugfs_mntpt[MAXPATHLEN - 1] = '\0';
if (envchanged)
*envchanged = 1;
(*argv)++;
(*argc)--;
} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
strncpy(debugfs_mntpt, cmd + strlen(CMD_DEBUGFS_DIR), MAXPATHLEN);
debugfs_mntpt[MAXPATHLEN - 1] = '\0';
if (envchanged)
*envchanged = 1;
} else {
fprintf(stderr, "Unknown option: %s\n", cmd);
usage(perf_usage_string);
}
(*argv)++;
(*argc)--;
handled++;
}
return handled;
}
static int handle_alias(int *argcp, const char ***argv)
{
int envchanged = 0, ret = 0, saved_errno = errno;
int count, option_count;
const char **new_argv;
const char *alias_command;
char *alias_string;
alias_command = (*argv)[0];
alias_string = alias_lookup(alias_command);
if (alias_string) {
if (alias_string[0] == '!') {
if (*argcp > 1) {
struct strbuf buf;
strbuf_init(&buf, PATH_MAX);
strbuf_addstr(&buf, alias_string);
sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
free(alias_string);
alias_string = buf.buf;
}
ret = system(alias_string + 1);
if (ret >= 0 && WIFEXITED(ret) &&
WEXITSTATUS(ret) != 127)
exit(WEXITSTATUS(ret));
die("Failed to run '%s' when expanding alias '%s'",
alias_string + 1, alias_command);
}
count = split_cmdline(alias_string, &new_argv);
if (count < 0)
die("Bad alias.%s string", alias_command);
option_count = handle_options(&new_argv, &count, &envchanged);
if (envchanged)
die("alias '%s' changes environment variables\n"
"You can use '!perf' in the alias to do this.",
alias_command);
memmove(new_argv - option_count, new_argv,
count * sizeof(char *));
new_argv -= option_count;
if (count < 1)
die("empty alias for %s", alias_command);
if (!strcmp(alias_command, new_argv[0]))
die("recursive alias: %s", alias_command);
new_argv = realloc(new_argv, sizeof(char *) *
(count + *argcp + 1));
/* insert after command name */
memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
new_argv[count + *argcp] = NULL;
*argv = new_argv;
*argcp += count - 1;
ret = 1;
}
errno = saved_errno;
return ret;
}
const char perf_version_string[] = PERF_VERSION;
#define RUN_SETUP (1<<0)
#define USE_PAGER (1<<1)
/*
* require working tree to be present -- anything uses this needs
* RUN_SETUP for reading from the configuration file.
*/
#define NEED_WORK_TREE (1<<2)
struct cmd_struct {
const char *cmd;
int (*fn)(int, const char **, const char *);
int option;
};
static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
{
int status;
struct stat st;
const char *prefix;
prefix = NULL;
if (p->option & RUN_SETUP)
prefix = NULL; /* setup_perf_directory(); */
if (use_pager == -1 && p->option & RUN_SETUP)
use_pager = check_pager_config(p->cmd);
if (use_pager == -1 && p->option & USE_PAGER)
use_pager = 1;
commit_pager_choice();
set_debugfs_path();
status = p->fn(argc, argv, prefix);
if (status)
return status & 0xff;
/* Somebody closed stdout? */
if (fstat(fileno(stdout), &st))
return 0;
/* Ignore write errors for pipes and sockets.. */
if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
return 0;
/* Check for ENOSPC and EIO errors.. */
if (fflush(stdout))
die("write failure on standard output: %s", strerror(errno));
if (ferror(stdout))
die("unknown write failure on standard output");
if (fclose(stdout))
die("close failed on standard output: %s", strerror(errno));
return 0;
}
static void handle_internal_command(int argc, const char **argv)
{
const char *cmd = argv[0];
static struct cmd_struct commands[] = {
{ "buildid-cache", cmd_buildid_cache, 0 },
{ "buildid-list", cmd_buildid_list, 0 },
{ "diff", cmd_diff, 0 },
{ "help", cmd_help, 0 },
{ "list", cmd_list, 0 },
{ "record", cmd_record, 0 },
{ "report", cmd_report, 0 },
{ "bench", cmd_bench, 0 },
{ "stat", cmd_stat, 0 },
{ "timechart", cmd_timechart, 0 },
{ "top", cmd_top, 0 },
{ "annotate", cmd_annotate, 0 },
{ "version", cmd_version, 0 },
{ "trace", cmd_trace, 0 },
{ "sched", cmd_sched, 0 },
{ "probe", cmd_probe, 0 },
{ "kmem", cmd_kmem, 0 },
{ "lock", cmd_lock, 0 },
};
unsigned int i;
static const char ext[] = STRIP_EXTENSION;
if (sizeof(ext) > 1) {
i = strlen(argv[0]) - strlen(ext);
if (i > 0 && !strcmp(argv[0] + i, ext)) {
char *argv0 = strdup(argv[0]);
argv[0] = cmd = argv0;
argv0[i] = '\0';
}
}
/* Turn "perf cmd --help" into "perf help cmd" */
if (argc > 1 && !strcmp(argv[1], "--help")) {
argv[1] = argv[0];
argv[0] = cmd = "help";
}
for (i = 0; i < ARRAY_SIZE(commands); i++) {
struct cmd_struct *p = commands+i;
if (strcmp(p->cmd, cmd))
continue;
exit(run_builtin(p, argc, argv));
}
}
static void execv_dashed_external(const char **argv)
{
struct strbuf cmd = STRBUF_INIT;
const char *tmp;
int status;
strbuf_addf(&cmd, "perf-%s", argv[0]);
/*
* argv[0] must be the perf command, but the argv array
* belongs to the caller, and may be reused in
* subsequent loop iterations. Save argv[0] and
* restore it on error.
*/
tmp = argv[0];
argv[0] = cmd.buf;
/*
* if we fail because the command is not found, it is
* OK to return. Otherwise, we just pass along the status code.
*/
status = run_command_v_opt(argv, 0);
if (status != -ERR_RUN_COMMAND_EXEC) {
if (IS_RUN_COMMAND_ERR(status))
die("unable to run '%s'", argv[0]);
exit(-status);
}
errno = ENOENT; /* as if we called execvp */
argv[0] = tmp;
strbuf_release(&cmd);
}
static int run_argv(int *argcp, const char ***argv)
{
int done_alias = 0;
while (1) {
/* See if it's an internal command */
handle_internal_command(*argcp, *argv);
/* .. then try the external ones */
execv_dashed_external(*argv);
/* It could be an alias -- this works around the insanity
* of overriding "perf log" with "perf show" by having
* alias.log = show
*/
if (done_alias || !handle_alias(argcp, argv))
break;
done_alias = 1;
}
return done_alias;
}
/* mini /proc/mounts parser: searching for "^blah /mount/point debugfs" */
static void get_debugfs_mntpt(void)
{
const char *path = debugfs_mount(NULL);
if (path)
strncpy(debugfs_mntpt, path, sizeof(debugfs_mntpt));
else
debugfs_mntpt[0] = '\0';
}
int main(int argc, const char **argv)
{
const char *cmd;
cmd = perf_extract_argv0_path(argv[0]);
if (!cmd)
cmd = "perf-help";
/* get debugfs mount point from /proc/mounts */
get_debugfs_mntpt();
/*
* "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, and
* die if that one cannot handle it.
*/
if (!prefixcmp(cmd, "perf-")) {
cmd += 5;
argv[0] = cmd;
handle_internal_command(argc, argv);
die("cannot handle %s internally", cmd);
}
/* Look for flags.. */
argv++;
argc--;
handle_options(&argv, &argc, NULL);
commit_pager_choice();
set_debugfs_path();
if (argc > 0) {
if (!prefixcmp(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);
exit(1);
}
cmd = argv[0];
/*
* 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();
while (1) {
static int done_help;
static int was_alias;
was_alias = run_argv(&argc, &argv);
if (errno != ENOENT)
break;
if (was_alias) {
fprintf(stderr, "Expansion of alias '%s' failed; "
"'%s' is not a perf-command\n",
cmd, argv[0]);
exit(1);
}
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, strerror(errno));
return 1;
}