From: Ingo Molnar <mingo@kernel.org>
To: Borislav Petkov <bp@alien8.de>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Robert Richter <rric@kernel.org>, Vince Weaver <vince@deater.net>,
lkml <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH] perf/stat: Add --disable-hwdt
Date: Mon, 6 Feb 2017 13:44:48 +0100 [thread overview]
Message-ID: <20170206124447.GA12772@gmail.com> (raw)
In-Reply-To: <20170206124116.7jmrmufthqtnd3dc@pd.tnic>
* Borislav Petkov <bp@alien8.de> wrote:
> On Mon, Feb 06, 2017 at 01:22:31PM +0100, Ingo Molnar wrote:
> > Looks sensible, and I'd in fact make this the new default behavior (if root runs
> > perf stat) - i.e. add a flag to re-enable it, for the rare case where we want to
> > debug a hard deadlock while running perf stat ...
>
> I'd probably only need to save the previous state, in case it was
> disabled for whatever reason.
>
> So actually, I'll make it so that we restore the previous state at exit.
> Whatever it was. But while perf stat runs as root, we will disable it by
> default.
>
> /me scratches head a bit...
>
> Oh ok, even better - no need for a cmdline option then.
>
> Or does it *ever* make sense to have watchdog running *while* perf stat
> runs too?
Yeah, if for some whatever reason perf locks up while running perf stat as root,
so I'd keep the option, as a general principle. :-/
Thanks,
Ingo
next prev parent reply other threads:[~2017-02-06 12:44 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-06 12:15 [RFC PATCH] perf/stat: Add --disable-hwdt Borislav Petkov
2017-02-06 12:22 ` Ingo Molnar
2017-02-06 12:41 ` Borislav Petkov
2017-02-06 12:44 ` Ingo Molnar [this message]
2017-02-06 12:49 ` Borislav Petkov
2017-02-06 13:18 ` Robert Richter
2017-02-06 13:23 ` Borislav Petkov
2017-02-07 7:25 ` Ingo Molnar
2017-02-07 10:54 ` Borislav Petkov
2017-02-07 15:06 ` Borislav Petkov
2017-02-11 17:03 ` Borislav Petkov
2017-02-11 17:59 ` Ingo Molnar
2017-02-11 18:32 ` Borislav Petkov
2017-02-11 20:41 ` Ingo Molnar
2017-03-07 7:21 ` [tip:perf/core] perf stat: Issue a HW watchdog disable hint tip-bot for Borislav Petkov
2017-02-06 14:23 ` [RFC PATCH] perf/stat: Add --disable-hwdt Vince Weaver
2017-02-06 17:02 ` Borislav Petkov
2017-02-07 1:08 ` Borislav Petkov
2017-02-07 1:09 ` [PATCH 1/2] tools/lib/api/fs: Add procfs int read/write helpers Borislav Petkov
2017-02-07 1:43 ` Arnaldo Carvalho de Melo
2017-02-07 10:30 ` Borislav Petkov
2017-02-07 15:00 ` Arnaldo Carvalho de Melo
2017-02-07 15:08 ` Borislav Petkov
2017-02-07 15:34 ` Arnaldo Carvalho de Melo
2017-02-07 1:10 ` [PATCH 2/2] perf stat: Disable HW watchdog around a perf stat session Borislav Petkov
2017-02-07 1:45 ` Arnaldo Carvalho de Melo
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=20170206124447.GA12772@gmail.com \
--to=mingo@kernel.org \
--cc=acme@kernel.org \
--cc=bp@alien8.de \
--cc=linux-kernel@vger.kernel.org \
--cc=peterz@infradead.org \
--cc=rric@kernel.org \
--cc=vince@deater.net \
/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