linux-kernel - [PATCH 2/2 -tip] perf: Don't generate events for the idle task when exclude

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	22 Oct 2009 18:34:08 +0200
From:	Soeren Sandmann <sandmann@...mi.au.dk>
To:	linux-kernel@...r.kernel.org
Cc:	Ingo Molnar <mingo@...e.hu>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Fr??d??ric Weisbecker <fweisbec@...il.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Arnaldo Carvalho de Melo <acme@...hat.com>,
	Steven Rostedt <rostedt@...dmis.org>
Subject: [PATCH 2/2 -tip] perf: Don't generate events for the idle task when exclude_idle is set.

Getting samples for the idle task is often not interesting, so don't
generate them when exclude_idle is set for the event in question.

Signed-off-by: SÃ¸ren Sandmann Pedersen <sandmann@...hat.com>
---
 kernel/perf_event.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index b492c55..7bc84cb 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -3959,8 +3959,9 @@ static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer)
 		regs = task_pt_regs(current);
 
 	if (regs) {
-		if (perf_event_overflow(event, 0, &data, regs))
-			ret = HRTIMER_NORESTART;
+		if (!(event->attr.exclude_idle && current->pid == 0))
+			if (perf_event_overflow(event, 0, &data, regs))
+				ret = HRTIMER_NORESTART;
 	}
 
 	period = max_t(u64, 10000, event->hw.sample_period);
-- 
1.6.5.rc2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/