perf sched timehist: Add call graph options

If callchains were recorded they are appended to the line with a default stack depth of 5:

  1.874569 [0011] gcc[31949]       0.014 0.000 1.148 wait_for_completion_killable <- do_fork <- sys_vfork <- stub_vfork <- __vfork
  1.874591 [0010] gcc[31951]       0.000 0.000 0.024 __cond_resched <- _cond_resched <- wait_for_completion <- stop_one_cpu <- sched_exec
  1.874603 [0010] migration/10[59] 3.350 0.004 0.011 smpboot_thread_fn <- kthread <- ret_from_fork
  1.874604 [0011] <idle>           1.148 0.000 0.035 cpu_startup_entry <- start_secondary
  1.874723 [0005] <idle>           0.016 0.000 1.383 cpu_startup_entry <- start_secondary
  1.874746 [0005] gcc[31949]       0.153 0.078 0.022 do_wait sys_wait4 <- system_call_fastpath <- __GI___waitpid

 --no-call-graph can be used to not show the callchains. --max-stack is used
to control the number of frames shown (default of 5). -x/--excl options can
be used to collapse redundant callchains to get more relevant data on screen.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/20161116060634.28477-7-namhyung@kernel.org
[ Add documentation based on above commit message ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
David Ahern 2016-11-16 15:06:32 +09:00 committed by Arnaldo Carvalho de Melo
parent fc1469f1b2
commit 6c973c9085
2 changed files with 89 additions and 6 deletions

View file

@ -99,6 +99,13 @@ OPTIONS for 'perf sched timehist'
--kallsyms=<file>::
kallsyms pathname
-g::
--no-call-graph::
Do not display call chains if present.
--max-stack::
Maximum number of functions to display in backtrace, default 5.
-s::
--summary::
Show only a summary of scheduling by thread with min, max, and average

View file

@ -14,6 +14,7 @@
#include "util/thread_map.h"
#include "util/color.h"
#include "util/stat.h"
#include "util/callchain.h"
#include <subcmd/parse-options.h>
#include "util/trace-event.h"
@ -198,6 +199,8 @@ struct perf_sched {
/* options for timehist command */
bool summary;
bool summary_only;
bool show_callchain;
unsigned int max_stack;
bool show_wakeups;
u64 skipped_samples;
};
@ -1810,6 +1813,7 @@ static void timehist_header(void)
static void timehist_print_sample(struct perf_sched *sched,
struct perf_sample *sample,
struct addr_location *al,
struct thread *thread)
{
struct thread_runtime *tr = thread__priv(thread);
@ -1827,6 +1831,18 @@ static void timehist_print_sample(struct perf_sched *sched,
if (sched->show_wakeups)
printf(" %-*s", comm_width, "");
if (thread->tid == 0)
goto out;
if (sched->show_callchain)
printf(" ");
sample__fprintf_sym(sample, al, 0,
EVSEL__PRINT_SYM | EVSEL__PRINT_ONELINE |
EVSEL__PRINT_CALLCHAIN_ARROW,
&callchain_cursor, stdout);
out:
printf("\n");
}
@ -1878,9 +1894,14 @@ static void timehist_update_runtime_stats(struct thread_runtime *r,
r->total_run_time += r->dt_run;
}
static bool is_idle_sample(struct perf_sample *sample,
struct perf_evsel *evsel)
static bool is_idle_sample(struct perf_sched *sched,
struct perf_sample *sample,
struct perf_evsel *evsel,
struct machine *machine)
{
struct thread *thread;
struct callchain_cursor *cursor = &callchain_cursor;
/* pid 0 == swapper == idle task */
if (sample->pid == 0)
return true;
@ -1889,6 +1910,25 @@ static bool is_idle_sample(struct perf_sample *sample,
if (perf_evsel__intval(evsel, sample, "prev_pid") == 0)
return true;
}
/* want main thread for process - has maps */
thread = machine__findnew_thread(machine, sample->pid, sample->pid);
if (thread == NULL) {
pr_debug("Failed to get thread for pid %d.\n", sample->pid);
return false;
}
if (!symbol_conf.use_callchain || sample->callchain == NULL)
return false;
if (thread__resolve_callchain(thread, cursor, evsel, sample,
NULL, NULL, sched->max_stack) != 0) {
if (verbose)
error("Failed to resolve callchain. Skipping\n");
return false;
}
callchain_cursor_commit(cursor);
return false;
}
@ -1999,13 +2039,14 @@ static struct thread_runtime *thread__get_runtime(struct thread *thread)
return tr;
}
static struct thread *timehist_get_thread(struct perf_sample *sample,
static struct thread *timehist_get_thread(struct perf_sched *sched,
struct perf_sample *sample,
struct machine *machine,
struct perf_evsel *evsel)
{
struct thread *thread;
if (is_idle_sample(sample, evsel)) {
if (is_idle_sample(sched, sample, evsel, machine)) {
thread = get_idle_thread(sample->cpu);
if (thread == NULL)
pr_err("Failed to get idle thread for cpu %d.\n", sample->cpu);
@ -2115,7 +2156,7 @@ static int timehist_sched_change_event(struct perf_tool *tool,
goto out;
}
thread = timehist_get_thread(sample, machine, evsel);
thread = timehist_get_thread(sched, sample, machine, evsel);
if (thread == NULL) {
rc = -1;
goto out;
@ -2134,7 +2175,7 @@ static int timehist_sched_change_event(struct perf_tool *tool,
timehist_update_runtime_stats(tr, sample->time, tprev);
if (!sched->summary_only)
timehist_print_sample(sched, sample, thread);
timehist_print_sample(sched, sample, &al, thread);
out:
if (tr) {
@ -2327,6 +2368,30 @@ static int perf_timehist__process_sample(struct perf_tool *tool,
return err;
}
static int timehist_check_attr(struct perf_sched *sched,
struct perf_evlist *evlist)
{
struct perf_evsel *evsel;
struct evsel_runtime *er;
list_for_each_entry(evsel, &evlist->entries, node) {
er = perf_evsel__get_runtime(evsel);
if (er == NULL) {
pr_err("Failed to allocate memory for evsel runtime data\n");
return -1;
}
if (sched->show_callchain &&
!(evsel->attr.sample_type & PERF_SAMPLE_CALLCHAIN)) {
pr_info("Samples do not have callchains.\n");
sched->show_callchain = 0;
symbol_conf.use_callchain = 0;
}
}
return 0;
}
static int perf_sched__timehist(struct perf_sched *sched)
{
const struct perf_evsel_str_handler handlers[] = {
@ -2359,6 +2424,8 @@ static int perf_sched__timehist(struct perf_sched *sched)
sched->tool.ordered_events = true;
sched->tool.ordering_requires_timestamps = true;
symbol_conf.use_callchain = sched->show_callchain;
session = perf_session__new(&file, false, &sched->tool);
if (session == NULL)
return -ENOMEM;
@ -2367,6 +2434,9 @@ static int perf_sched__timehist(struct perf_sched *sched)
symbol__init(&session->header.env);
if (timehist_check_attr(sched, evlist) != 0)
goto out;
setup_pager();
/* setup per-evsel handlers */
@ -2714,6 +2784,8 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
.next_shortname1 = 'A',
.next_shortname2 = '0',
.skip_merge = 0,
.show_callchain = 1,
.max_stack = 5,
};
const struct option sched_options[] = {
OPT_STRING('i', "input", &input_name, "file",
@ -2759,6 +2831,10 @@ int cmd_sched(int argc, const char **argv, const char *prefix __maybe_unused)
"file", "vmlinux pathname"),
OPT_STRING(0, "kallsyms", &symbol_conf.kallsyms_name,
"file", "kallsyms pathname"),
OPT_BOOLEAN('g', "call-graph", &sched.show_callchain,
"Display call chains if present (default on)"),
OPT_UINTEGER(0, "max-stack", &sched.max_stack,
"Maximum number of functions to display backtrace."),
OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
"Look for files with symbols relative to this directory"),
OPT_BOOLEAN('s', "summary", &sched.summary_only,