From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Steets <asteets@rgmadvisors.com>,
linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
Paul Mackerras <paulus@samba.org>,
Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Subject: Re: perf: prctl(PR_TASK_PERF_EVENTS_DISABLE) has no effect
Date: Mon, 30 Jan 2012 10:52:36 +0100 [thread overview]
Message-ID: <1327917156.2446.191.camel@twins> (raw)
In-Reply-To: <20120129163235.GB23408@elte.hu>
On Sun, 2012-01-29 at 17:32 +0100, Ingo Molnar wrote:
> * Andrew Steets <asteets@rgmadvisors.com> wrote:
>
> > On 1/28/12 6:01 AM, Ingo Molnar wrote:
> >
> > >> prctl(PR_TASK_PERF_EVENTS_DISABLE) doesn't appear to
> > >> disable perf event counters. Here is a demonstration
> > >> program:
> > >
> > > btw., what's your usecase?
> >
> > I'm trying to profile a small section of a long-running
> > program. I ran into trouble using call-graph recording and I
> > thought this might be an alternative way of getting what I was
> > after.
>
> That usecase indeed makes sense. Peter, could we allow this for
> privileged tasks, depending on the perf_paranoia settings or
> such?
I really dislike it. The sane way around this would be to allow easy
self-profiling instead of doing things arse about face like that.
next prev parent reply other threads:[~2012-01-30 9:52 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-27 17:03 perf: prctl(PR_TASK_PERF_EVENTS_DISABLE) has no effect Andrew Steets
2012-01-27 17:12 ` Peter Zijlstra
2012-01-27 20:06 ` Andrew Steets
2012-01-27 21:34 ` Peter Zijlstra
2012-01-28 12:01 ` Ingo Molnar
2012-01-28 23:48 ` Andrew Steets
2012-01-29 16:32 ` Ingo Molnar
2012-01-29 17:50 ` Gleb Natapov
2012-01-30 9:52 ` Peter Zijlstra [this message]
2012-01-30 10:11 ` Ingo Molnar
2012-01-30 11:01 ` Peter Zijlstra
2012-01-30 11:31 ` Ingo Molnar
2012-01-30 13:45 ` Peter Zijlstra
2012-01-30 13:58 ` Ingo Molnar
2012-01-30 15:30 ` Arnaldo Carvalho de Melo
2012-01-30 15:29 ` Arnaldo Carvalho de Melo
2012-02-01 19:03 ` Frederic Weisbecker
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=1327917156.2446.191.camel@twins \
--to=a.p.zijlstra@chello.nl \
--cc=acme@ghostprotocols.net \
--cc=asteets@rgmadvisors.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=paulus@samba.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).