mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 10:49:33 +00:00
![Jason Baron](/assets/img/avatar_default.png)
If "/sys/kernel/debug" is not a debugfs mount point, search for the debugfs filesystem in /proc/mounts, but also allows the user to specify '--debugfs-dir=blah' or set the environment variable: 'PERF_DEBUGFS_DIR' Signed-off-by: Jason Baron <jbaron@redhat.com> [ also made it probe "/debug" by default ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20090721181629.GA3094@redhat.com>
500 lines
12 KiB
C
500 lines
12 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"
|
|
|
|
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, "--exec-path")) {
|
|
cmd += 11;
|
|
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, "--perf-dir=")) {
|
|
setenv(PERF_DIR_ENVIRONMENT, cmd + 10, 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, "--work-tree=")) {
|
|
setenv(PERF_WORK_TREE_ENVIRONMENT, cmd + 12, 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, "--debugfs-dir=")) {
|
|
strncpy(debugfs_mntpt, cmd + 14, 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[] = {
|
|
{ "help", cmd_help, 0 },
|
|
{ "list", cmd_list, 0 },
|
|
{ "record", cmd_record, 0 },
|
|
{ "report", cmd_report, 0 },
|
|
{ "stat", cmd_stat, 0 },
|
|
{ "top", cmd_top, 0 },
|
|
{ "annotate", cmd_annotate, 0 },
|
|
{ "version", cmd_version, 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)
|
|
{
|
|
FILE *file;
|
|
char fs_type[100];
|
|
char debugfs[MAXPATHLEN];
|
|
|
|
/*
|
|
* try the standard location
|
|
*/
|
|
if (valid_debugfs_mount("/sys/kernel/debug/") == 0) {
|
|
strcpy(debugfs_mntpt, "/sys/kernel/debug/");
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* try the sane location
|
|
*/
|
|
if (valid_debugfs_mount("/debug/") == 0) {
|
|
strcpy(debugfs_mntpt, "/debug/");
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* give up and parse /proc/mounts
|
|
*/
|
|
file = fopen("/proc/mounts", "r");
|
|
if (file == NULL)
|
|
return;
|
|
|
|
while (fscanf(file, "%*s %"
|
|
STR(MAXPATHLEN)
|
|
"s %99s %*s %*d %*d\n",
|
|
debugfs, fs_type) == 2) {
|
|
if (strcmp(fs_type, "debugfs") == 0)
|
|
break;
|
|
}
|
|
fclose(file);
|
|
if (strcmp(fs_type, "debugfs") == 0) {
|
|
strncpy(debugfs_mntpt, debugfs, MAXPATHLEN);
|
|
debugfs_mntpt[MAXPATHLEN - 1] = '\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
|
|
* precidence 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 = 0;
|
|
static int was_alias = 0;
|
|
|
|
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;
|
|
}
|