public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: paulmck@linux.vnet.ibm.com
Cc: bunk@kernel.org, josh@kernel.org, linux-kernel@vger.kernel.org,
	mingo@elte.hu
Subject: Re: [PATCH] Make rcutorture RNG use temporal entropy
Date: Fri, 17 Aug 2007 11:53:56 -0700	[thread overview]
Message-ID: <20070817115356.cb201e42.akpm@linux-foundation.org> (raw)
In-Reply-To: <20070816024904.GA5312@linux.vnet.ibm.com>

On Wed, 15 Aug 2007 19:49:04 -0700
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com> wrote:

> Repost of http://lkml.org/lkml/2007/8/10/472 made available by request.
> 
> The locking used by get_random_bytes() can conflict with the
> preempt_disable() and synchronize_sched() form of RCU.  This patch changes
> rcutorture's RNG to gather entropy from the new cpu_clock() interface
> (relying on interrupts, preemption, daemons, and rcutorture's reader
> thread's rock-bottom scheduling priority to provide useful entropy),
> and also adds and EXPORT_SYMBOL_GPL() to make that interface available
> to GPLed kernel modules such as rcutorture.
> 
> Passes several hours of rcutorture.

Please explain what "conflict with" means so that I can work out if
this is a needed-in-2.6.23 change, thanks.

  reply	other threads:[~2007-08-17 18:54 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-08-16  2:49 [PATCH] Make rcutorture RNG use temporal entropy Paul E. McKenney
2007-08-17 18:53 ` Andrew Morton [this message]
2007-08-17 20:00   ` Paul E. McKenney
2007-08-23 18:06     ` Matt Mackall
2007-08-23 18:58       ` Paul E. McKenney
2007-08-23 19:40         ` Matt Mackall
2007-08-28  1:15           ` Paul E. McKenney
2007-09-03 13:29             ` Matt Mackall
2007-09-03 20:09               ` Paul E. McKenney
2007-09-04  5:46 ` Satyam Sharma
2007-09-04 16:14   ` Paul E. McKenney
2007-09-04 17:47     ` Paul E. McKenney

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=20070817115356.cb201e42.akpm@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=bunk@kernel.org \
    --cc=josh@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=paulmck@linux.vnet.ibm.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