linux/tools/perf/perf.c
Namhyung Kim 14cbfbeb76 perf report: Show random usage tip on the help line
Currently perf report only shows a help message "For a higher level
overview, try: perf report --sort comm,dso" unconditionally (even if
the sort keys were used).  Add more help tips and show randomly.

Load tips from ${prefix}/share/doc/perf-tip/tips.txt file.

  $ perf report | tail
      0.10%  swapper  [kernel.vmlinux]   [k] irq_exit
      0.09%  swapper  [kernel.vmlinux]   [k] flush_smp_call_function_queue
      0.08%  swapper  [kernel.vmlinux]   [k] native_write_msr_safe
      0.03%  swapper  [kernel.vmlinux]   [k] group_sched_in
      0.01%  perf     [kernel.vmlinux]   [k] native_write_msr_safe

  #
  # (Tip: Search options using a keyword: perf report -h <keyword>)
  #

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1452166913-27046-1-git-send-email-namhyung@kernel.org
[ Renamed it to perf_tip() and the parameter dirname to dirpath to fix the build on older distros ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-01-08 13:15:46 -03:00

641 lines
15 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/env.h"
#include <subcmd/exec-cmd.h>
#include "util/cache.h"
#include "util/quote.h"
#include <subcmd/run-command.h>
#include "util/parse-events.h"
#include <subcmd/parse-options.h>
#include "util/bpf-loader.h"
#include "util/debug.h"
#include <api/fs/tracing_path.h>
#include <pthread.h>
#include <stdlib.h>
#include <time.h>
const char perf_usage_string[] =
"perf [--version] [--help] [OPTIONS] COMMAND [ARGS]";
const char perf_more_info_string[] =
"See 'perf help COMMAND' for more information on a specific command.";
int use_browser = -1;
static int use_pager = -1;
const char *input_name;
struct cmd_struct {
const char *cmd;
int (*fn)(int, const char **, const char *);
int option;
};
static struct cmd_struct commands[] = {
{ "buildid-cache", cmd_buildid_cache, 0 },
{ "buildid-list", cmd_buildid_list, 0 },
{ "config", cmd_config, 0 },
{ "diff", cmd_diff, 0 },
{ "evlist", cmd_evlist, 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 },
{ "script", cmd_script, 0 },
{ "sched", cmd_sched, 0 },
#ifdef HAVE_LIBELF_SUPPORT
{ "probe", cmd_probe, 0 },
#endif
{ "kmem", cmd_kmem, 0 },
{ "lock", cmd_lock, 0 },
{ "kvm", cmd_kvm, 0 },
{ "test", cmd_test, 0 },
#ifdef HAVE_LIBAUDIT_SUPPORT
{ "trace", cmd_trace, 0 },
#endif
{ "inject", cmd_inject, 0 },
{ "mem", cmd_mem, 0 },
{ "data", cmd_data, 0 },
};
struct pager_config {
const char *cmd;
int val;
};
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 int browser_command_config(const char *var, const char *value, void *data)
{
struct pager_config *c = data;
if (!prefixcmp(var, "tui.") && !strcmp(var + 4, c->cmd))
c->val = perf_config_bool(var, value);
if (!prefixcmp(var, "gtk.") && !strcmp(var + 4, c->cmd))
c->val = perf_config_bool(var, value) ? 2 : 0;
return 0;
}
/*
* returns 0 for "no tui", 1 for "use tui", 2 for "use gtk",
* and -1 for "not specified"
*/
static int check_browser_config(const char *cmd)
{
struct pager_config c;
c.cmd = cmd;
c.val = -1;
perf_config(browser_command_config, &c);
return c.val;
}
static void commit_pager_choice(void)
{
switch (use_pager) {
case 0:
setenv(PERF_PAGER_ENVIRONMENT, "cat", 1);
break;
case 1:
/* setup_pager(); */
break;
default:
break;
}
}
struct option options[] = {
OPT_ARGUMENT("help", "help"),
OPT_ARGUMENT("version", "version"),
OPT_ARGUMENT("exec-path", "exec-path"),
OPT_ARGUMENT("html-path", "html-path"),
OPT_ARGUMENT("paginate", "paginate"),
OPT_ARGUMENT("no-pager", "no-pager"),
OPT_ARGUMENT("perf-dir", "perf-dir"),
OPT_ARGUMENT("work-tree", "work-tree"),
OPT_ARGUMENT("debugfs-dir", "debugfs-dir"),
OPT_ARGUMENT("buildid-dir", "buildid-dir"),
OPT_ARGUMENT("list-cmds", "list-cmds"),
OPT_ARGUMENT("list-opts", "list-opts"),
OPT_ARGUMENT("debug", "debug"),
OPT_END()
};
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;
/*
* Shortcut for '-h' and '-v' options to invoke help
* and version command.
*/
if (!strcmp(cmd, "-h")) {
(*argv)[0] = "--help";
break;
}
if (!strcmp(cmd, "-v")) {
(*argv)[0] = "--version";
break;
}
/*
* Check remaining flags.
*/
if (!prefixcmp(cmd, CMD_EXEC_PATH)) {
cmd += strlen(CMD_EXEC_PATH);
if (*cmd == '=')
set_argv_exec_path(cmd + 1);
else {
puts(get_argv_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);
}
tracing_path_set((*argv)[1]);
if (envchanged)
*envchanged = 1;
(*argv)++;
(*argc)--;
} else if (!strcmp(cmd, "--buildid-dir")) {
if (*argc < 2) {
fprintf(stderr, "No directory given for --buildid-dir.\n");
usage(perf_usage_string);
}
set_buildid_dir((*argv)[1]);
if (envchanged)
*envchanged = 1;
(*argv)++;
(*argc)--;
} else if (!prefixcmp(cmd, CMD_DEBUGFS_DIR)) {
tracing_path_set(cmd + strlen(CMD_DEBUGFS_DIR));
fprintf(stderr, "dir: %s\n", tracing_path);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--list-cmds")) {
unsigned int i;
for (i = 0; i < ARRAY_SIZE(commands); i++) {
struct cmd_struct *p = commands+i;
printf("%s ", p->cmd);
}
putchar('\n');
exit(0);
} else if (!strcmp(cmd, "--list-opts")) {
unsigned int i;
for (i = 0; i < ARRAY_SIZE(options)-1; i++) {
struct option *p = options+i;
printf("--%s ", p->long_name);
}
putchar('\n');
exit(0);
} else if (!strcmp(cmd, "--debug")) {
if (*argc < 2) {
fprintf(stderr, "No variable specified for --debug.\n");
usage(perf_usage_string);
}
if (perf_debug_option((*argv)[1]))
usage(perf_usage_string);
(*argv)++;
(*argc)--;
} 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)
static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
{
int status;
struct stat st;
const char *prefix;
char sbuf[STRERR_BUFSIZE];
prefix = NULL;
if (p->option & RUN_SETUP)
prefix = NULL; /* setup_perf_directory(); */
if (use_browser == -1)
use_browser = check_browser_config(p->cmd);
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();
perf_env__set_cmdline(&perf_env, argc, argv);
status = p->fn(argc, argv, prefix);
exit_browser(status);
perf_env__exit(&perf_env);
bpf__clear();
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;
status = 1;
/* Check for ENOSPC and EIO errors.. */
if (fflush(stdout)) {
fprintf(stderr, "write failure on standard output: %s",
strerror_r(errno, sbuf, sizeof(sbuf)));
goto out;
}
if (ferror(stdout)) {
fprintf(stderr, "unknown write failure on standard output");
goto out;
}
if (fclose(stdout)) {
fprintf(stderr, "close failed on standard output: %s",
strerror_r(errno, sbuf, sizeof(sbuf)));
goto out;
}
status = 0;
out:
return status;
}
static void handle_internal_command(int argc, const char **argv)
{
const char *cmd = argv[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;
}
static void pthread__block_sigwinch(void)
{
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGWINCH);
pthread_sigmask(SIG_BLOCK, &set, NULL);
}
void pthread__unblock_sigwinch(void)
{
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGWINCH);
pthread_sigmask(SIG_UNBLOCK, &set, NULL);
}
int main(int argc, const char **argv)
{
const char *cmd;
char sbuf[STRERR_BUFSIZE];
/* 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);
cacheline_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
cmd = extract_argv0_path(argv[0]);
if (!cmd)
cmd = "perf-help";
srandom(time(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, and
* die if that one cannot handle it.
*/
if (!prefixcmp(cmd, "perf-")) {
cmd += 5;
argv[0] = cmd;
handle_internal_command(argc, argv);
fprintf(stderr, "cannot handle %s internally", cmd);
goto out;
}
if (!prefixcmp(cmd, "trace")) {
#ifdef HAVE_LIBAUDIT_SUPPORT
set_buildid_dir(NULL);
setup_path();
argv[0] = "trace";
return cmd_trace(argc, argv, NULL);
#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();
set_buildid_dir(NULL);
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);
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();
while (1) {
static int done_help;
int 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]);
goto out;
}
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_r(errno, sbuf, sizeof(sbuf)));
out:
return 1;
}