linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: linux-kernel@vger.kernel.org, Namhyung Kim <namhyung@kernel.org>,
	Andi Kleen <andi@firstfloor.org>, Jiri Olsa <jolsa@kernel.org>,
	Minchan Kim <minchan@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Arnaldo Carvalho de Melo <acme@redhat.com>
Subject: [PATCH 04/29] perf sched timehist: Save callchain when entering idle
Date: Tue, 20 Dec 2016 14:03:33 -0300	[thread overview]
Message-ID: <20161220170358.4350-5-acme@kernel.org> (raw)
In-Reply-To: <20161220170358.4350-1-acme@kernel.org>

From: Namhyung Kim <namhyung@kernel.org>

In order to investigate the idleness reason, it is necessary to keep the
callchains when entering idle.  This can be identified by the
sched:sched_switch event having the next_pid field as 0.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161208144755.16673-4-namhyung@kernel.org
Link: http://lkml.kernel.org/r/20161213080632.19099-1-namhyung@kernel.org
[ Merged fix from Namhyung, see second Link: tag ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-sched.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index e108b0f6a246..dc83b803ca54 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -200,6 +200,7 @@ struct perf_sched {
 	/* options for timehist command */
 	bool		summary;
 	bool		summary_only;
+	bool		idle_hist;
 	bool		show_callchain;
 	unsigned int	max_stack;
 	bool		show_cpu_visual;
@@ -2101,6 +2102,15 @@ static struct thread *get_idle_thread(int cpu)
 	return idle_threads[cpu];
 }
 
+static void save_idle_callchain(struct idle_thread_runtime *itr,
+				struct perf_sample *sample)
+{
+	if (!symbol_conf.use_callchain || sample->callchain == NULL)
+		return;
+
+	callchain_cursor__copy(&itr->cursor, &callchain_cursor);
+}
+
 /*
  * handle runtime stats saved per thread
  */
@@ -2154,6 +2164,26 @@ static struct thread *timehist_get_thread(struct perf_sched *sched,
 		}
 
 		save_task_callchain(sched, sample, evsel, machine);
+		if (sched->idle_hist) {
+			struct thread *idle;
+			struct idle_thread_runtime *itr;
+
+			idle = get_idle_thread(sample->cpu);
+			if (idle == NULL) {
+				pr_err("Failed to get idle thread for cpu %d.\n", sample->cpu);
+				return NULL;
+			}
+
+			itr = thread__priv(idle);
+			if (itr == NULL)
+				return NULL;
+
+			itr->last_thread = thread;
+
+			/* copy task callchain when entering to idle */
+			if (perf_evsel__intval(evsel, sample, "next_pid") == 0)
+				save_idle_callchain(itr, sample);
+		}
 	}
 
 	return thread;
-- 
2.9.3

  parent reply	other threads:[~2016-12-20 17:05 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-12-20 17:03 [GIT PULL 00/29] perf/core improvements and fixes Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 01/29] perf tools: Move headers check into bash script Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 02/29] perf sched timehist: Split is_idle_sample() Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 03/29] perf sched timehist: Introduce struct idle_time_data Arnaldo Carvalho de Melo
2016-12-20 17:03 ` Arnaldo Carvalho de Melo [this message]
2016-12-20 17:03 ` [PATCH 05/29] perf sched timehist: Skip non-idle events when necessary Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 06/29] perf sched timehist: Add -I/--idle-hist option Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 07/29] perf sched timehist: Show callchains for idle stat Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 08/29] perf tools: Remove some needless __maybe_unused Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 09/29] perf mem: Fix --all-user/--all-kernel options Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 10/29] perf evsel: Use variable instead of repeating lengthy FD macro Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 11/29] perf thread_map: Add thread_map__remove function Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 12/29] perf evsel: Allow to ignore missing pid Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 13/29] perf record: Force ignore_missing_thread for uid option Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 14/29] perf annotate: Support jump instruction with target as second operand Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 15/29] perf annotate: Fix jump target outside of function address range Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 16/29] tools lib bpf: Sync {tools,}/include/uapi/linux/bpf.h Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 17/29] tools lib bpf: use __u32 from linux/types.h Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 18/29] tools lib bpf: Add flags to bpf_create_map() Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 19/29] samples/bpf: Make samples more libbpf-centric Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 20/29] samples/bpf: Make perf_event_read() static Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 21/29] perf trace: Check if MAP_32BIT is defined (again) Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 22/29] perf bench futex: Fix lock-pi help string Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 23/29] perf annotate: Don't throw error for zero length symbols Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 24/29] perf diff: Do not overwrite valid build id Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 25/29] samples/bpf: Switch over to libbpf Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 26/29] tools lib bpf: Add bpf_prog_{attach,detach} Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 27/29] samples/bpf: Be consistent with bpf_load_program bpf_insn parameter Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 28/29] samples/bpf: Remove perf_event_open() declaration Arnaldo Carvalho de Melo
2016-12-20 17:03 ` [PATCH 29/29] samples/bpf: Move open_raw_sock to separate header Arnaldo Carvalho de Melo
2016-12-20 19:15 ` [GIT PULL 00/29] perf/core improvements and fixes Ingo Molnar

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20161220170358.4350-5-acme@kernel.org \
    --to=acme@kernel.org \
    --cc=acme@redhat.com \
    --cc=andi@firstfloor.org \
    --cc=jolsa@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=minchan@kernel.org \
    --cc=mingo@kernel.org \
    --cc=namhyung@kernel.org \
    --cc=peterz@infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).