LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Nigel Cunningham <nigel@nigel.suspend2.net>
To: paulmck@linux.vnet.ibm.com
Cc: linux-kernel@vger.kernel.org, mingo@elte.hu, tglx@linutronix.de,
	dipankar@in.ibm.com, tytso@us.ibm.com, dvhltc@us.ibm.com,
	oleg@tv-sign.ru, twoerner.k@gmail.com, josh@freedesktop.org,
	billh@gnuppy.monkey.org, nielsen.esben@googlemail.com,
	corbet@lwn.net
Subject: Re: [RFC PATCH -rt 2/2] RCU priority boosting additions to rcutorture
Date: Thu, 01 Feb 2007 13:12:16 +1100	[thread overview]
Message-ID: <1170295936.32500.1.camel@nigel.suspend2.net> (raw)
In-Reply-To: <20070201012653.GB22922@linux.vnet.ibm.com>

Hi Paul.

On Wed, 2007-01-31 at 17:26 -0800, Paul E. McKenney wrote:
> This patch adds an optional preemption kernel thread to the rcutorture
> tests.  This thread sets itself to a low RT priority and chews up CPU
> in 10-second bursts, verifying that grace periods progress during this
> 10-second interval.  Passes RCU torture testing on a 4-CPU (a pair of
> 2-CPU dies) 64-bit Xeon system.

[...]

> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> +static int rcu_torture_preempt(void *arg)
> +{
> +	int completedstart;
> +	int err;
> +	time_t gcstart;
> +	struct sched_param sp;
> +
> +	sp.sched_priority = MAX_RT_PRIO - 1;
> +	err = sched_setscheduler(current, SCHED_RR, &sp);
> +	if (err != 0)
> +		printk(KERN_ALERT "rcu_torture_preempt() priority err: %d\n",
> +		       err);
> +	current->flags |= PF_NOFREEZE;
> +
> +	do {
> +		completedstart = rcu_torture_completed();
> +		gcstart = xtime.tv_sec;
> +		while ((xtime.tv_sec - gcstart < 10) &&
> +		       (rcu_torture_completed() == completedstart))
> +			cond_resched();
> +		if (rcu_torture_completed() == completedstart)
> +			rcu_torture_preempt_errors++;
> +		schedule_timeout_interruptible(HZ);
> +	} while (!kthread_should_stop());
> +	return 0;
> +}

Does it need to be NOFREEZE? I would think that it should be frozen
during a suspend/hibernate.

Regards,

Nigel


  reply	other threads:[~2007-02-01  2:12 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-02-01  1:21 [RFC PATCH -rt 0/2] RCU priority boosting that survives vicious testing Paul E. McKenney
2007-02-01  1:24 ` [RFC PATCH -rt 1/2] " Paul E. McKenney
2007-02-01  8:23   ` Ingo Molnar
2007-02-02 15:56     ` Paul E. McKenney
2007-02-01  1:26 ` [RFC PATCH -rt 2/2] RCU priority boosting additions to rcutorture Paul E. McKenney
2007-02-01  2:12   ` Nigel Cunningham [this message]
2007-02-01  2:31     ` Paul E. McKenney
2007-02-01  2:42       ` Nigel Cunningham
2007-02-01  5:46         ` Paul E. McKenney
2007-02-01 22:13           ` Nigel Cunningham
  -- strict thread matches above, loose matches on Subject: below --
2007-01-25  2:11 [RFC PATCH -rt 0/2] RCU priority boosting that survives semi-vicious testing Paul E. McKenney
2007-01-25  2:14 ` [RFC PATCH -rt 1/2] " Paul E. McKenney
2007-01-25  2:23   ` [RFC PATCH -rt 2/2] RCU priority boosting additions to rcutorture Paul E. McKenney
2007-01-25  8:47     ` Josh Triplett
2007-01-25 18:01       ` Paul E. McKenney
2007-01-25 19:06         ` Josh Triplett
2007-01-26  1:52           ` Paul E. McKenney
2007-01-26  6:29             ` Josh Triplett
2007-01-29  2:11           ` Paul E. McKenney
2007-01-29  6:05             ` Josh Triplett

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=1170295936.32500.1.camel@nigel.suspend2.net \
    --to=nigel@nigel.suspend2.net \
    --cc=billh@gnuppy.monkey.org \
    --cc=corbet@lwn.net \
    --cc=dipankar@in.ibm.com \
    --cc=dvhltc@us.ibm.com \
    --cc=josh@freedesktop.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=nielsen.esben@googlemail.com \
    --cc=oleg@tv-sign.ru \
    --cc=paulmck@linux.vnet.ibm.com \
    --cc=tglx@linutronix.de \
    --cc=twoerner.k@gmail.com \
    --cc=tytso@us.ibm.com \
    --subject='Re: [RFC PATCH -rt 2/2] RCU priority boosting additions to rcutorture' \
    /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

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).