Commit 6c973c90 authored by David Ahern's avatar David Ahern Committed by Arnaldo Carvalho de Melo
Browse files

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: default avatarDavid Ahern <dsahern@gmail.com>
Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
Acked-by: default avatarIngo Molnar <mingo@kernel.org>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Tested-by: default avatarArnaldo 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: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent fc1469f1

tools/perf/Documentation/perf-sched.txt

+7 −0
Original line number Diff line number Diff line
@@ -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

tools/perf/builtin-sched.c

+82 −6
Original line number Diff line number Diff line
@@ -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,

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