public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Avi Kivity <avi@redhat.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Will Deacon <will.deacon@arm.com>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	Ingo Molnar <mingo@elte.hu>,
	"acme@ghostprotocols.net" <acme@ghostprotocols.net>,
	Jason Wessel <jason.wessel@windriver.com>
Subject: Re: [PATCH 1/3] perf: add context field to perf_event
Date: Tue, 12 Jul 2011 12:16:40 +0300	[thread overview]
Message-ID: <4E1C10F8.6010300@redhat.com> (raw)
In-Reply-To: <1310462046.14978.11.camel@twins>

On 07/12/2011 12:14 PM, Peter Zijlstra wrote:
> On Tue, 2011-07-12 at 12:08 +0300, Avi Kivity wrote:
> >  Similar, but with stronger guarantees: when the function is called,
> >  current == p, and the task was either sleeping or in userspace.
>
> If the task is sleeping, current can never be p.

The guarantee is that the task was sleeping just before the function is 
called.  Of course it's woken up to run the function.

The idea is that you run the function in a known safe point to avoid 
extra synchronization.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.


  reply	other threads:[~2011-07-12  9:17 UTC|newest]

Thread overview: 39+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-29 15:42 [PATCH 0/3] Preparatory perf patches for KVM PMU support Avi Kivity
2011-06-29 15:42 ` [PATCH 1/3] perf: add context field to perf_event Avi Kivity
2011-06-29 16:08   ` Frederic Weisbecker
2011-06-29 16:25     ` Avi Kivity
2011-06-29 16:27     ` Will Deacon
2011-07-04 13:58       ` Frederic Weisbecker
2011-07-04 14:10         ` Avi Kivity
2011-07-04 14:36           ` Frederic Weisbecker
2011-07-11 21:07             ` Will Deacon
2011-07-12  7:20               ` Avi Kivity
2011-07-12  8:38                 ` Peter Zijlstra
2011-07-12  9:08                   ` Avi Kivity
2011-07-12  9:14                     ` Peter Zijlstra
2011-07-12  9:16                       ` Avi Kivity [this message]
2011-07-12  9:18                         ` Peter Zijlstra
2011-07-12  9:27                           ` Avi Kivity
2011-07-12  9:31                             ` Peter Zijlstra
2011-07-12  9:36                               ` Avi Kivity
2011-07-12  9:42                                 ` Will Deacon
2011-07-12  9:41                               ` Joerg Roedel
2011-07-12  9:44                                 ` Avi Kivity
2011-07-12  9:48                                   ` Joerg Roedel
2011-07-12  9:55                                     ` Avi Kivity
2011-07-12 10:03                                       ` Joerg Roedel
2011-07-12 10:07                                         ` Avi Kivity
2011-07-12 10:24                                           ` Joerg Roedel
2011-07-12 10:36                                             ` Avi Kivity
2011-07-21 15:32                               ` Will Deacon
2011-07-21 15:36                                 ` Avi Kivity
2011-07-21 15:46                                   ` Will Deacon
2011-07-21 15:59                                     ` Avi Kivity
2011-07-21 16:37                                       ` Will Deacon
2011-07-05 14:30         ` Will Deacon
2011-07-05 14:34           ` Frederic Weisbecker
2011-07-01 15:24   ` [tip:perf/core] perf: Add " tip-bot for Avi Kivity
2011-06-29 15:42 ` [PATCH 2/3] x86, perf: add constraints for architectural PMU v1 Avi Kivity
2011-07-01 15:24   ` [tip:perf/core] x86, perf: Add constraints for architectural PMU tip-bot for Avi Kivity
2011-06-29 15:42 ` [PATCH 3/3] perf: export perf_event_refresh() to modules Avi Kivity
2011-07-01 15:25   ` [tip:perf/core] " tip-bot for Avi Kivity

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=4E1C10F8.6010300@redhat.com \
    --to=avi@redhat.com \
    --cc=a.p.zijlstra@chello.nl \
    --cc=acme@ghostprotocols.net \
    --cc=fweisbec@gmail.com \
    --cc=jason.wessel@windriver.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=will.deacon@arm.com \
    /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