public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Petr Tesarik <ptesarik@suse.cz>
To: "Luck, Tony" <tony.luck@intel.com>
Cc: "linux-ia64@vger.kernel.org" <linux-ia64@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Hedi Berriche <hedi@sgi.com>
Subject: Re: Serious problem with ticket spinlocks on ia64
Date: Fri, 27 Aug 2010 23:03:32 +0200	[thread overview]
Message-ID: <201008272303.34228.ptesarik@suse.cz> (raw)
In-Reply-To: <987664A83D2D224EAE907B061CE93D53015D91D3B7@orsmsx505.amr.corp.intel.com>

On Friday 27 of August 2010 22:29:41 Luck, Tony wrote:
> > If this is a memory ordering problem (and that seems quite plausible)
> > then a liberal sprinkling of "ia64_mf()" calls throughout the spinlock
> > routines would probably make it go away.
>
> I think I take this back ... if it were a memory ordering problem, then
> it could show up any time - not just at wrap-around.

One more idea. The wrap-around case is the only one when the high word is 
modified. This is in fact the only case when the fetchadd.acq competes with 
the st2.rel about the actual contents of that location. I don't know if it 
matters...

Petr Tesarik

  parent reply	other threads:[~2010-08-27 21:03 UTC|newest]

Thread overview: 36+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-08-27 13:37 Serious problem with ticket spinlocks on ia64 Petr Tesarik
2010-08-27 13:48 ` Hedi Berriche
2010-08-27 14:09   ` Petr Tesarik
2010-08-27 14:31     ` Hedi Berriche
2010-08-27 14:40       ` Petr Tesarik
2010-08-27 14:52         ` Hedi Berriche
2010-08-27 16:37           ` Petr Tesarik
2010-08-27 16:08 ` Luck, Tony
2010-08-27 17:16   ` Petr Tesarik
2010-08-27 18:20     ` Hedi Berriche
2010-08-27 19:40     ` Petr Tesarik
2010-08-27 20:29   ` Luck, Tony
2010-08-27 20:41     ` Petr Tesarik
2010-08-27 21:03     ` Petr Tesarik [this message]
2010-08-27 21:11       ` Luck, Tony
2010-08-27 22:13         ` Petr Tesarik
2010-08-27 23:26           ` Luck, Tony
2010-08-27 23:55             ` Luck, Tony
2010-08-28  0:28               ` Hedi Berriche
2010-08-28  5:01                 ` Luck, Tony
2010-08-30 18:17                   ` Luck, Tony
2010-08-30 21:41                     ` Petr Tesarik
2010-08-30 22:43                       ` Tony Luck
2010-08-31 22:17                         ` Tony Luck
2010-09-01 23:09                           ` Tony Luck
2010-09-02  0:26                             ` Hedi Berriche
2010-09-03  0:06                               ` Tony Luck
2010-09-03  9:04                                 ` Petr Tesarik
2010-09-03 14:35                                   ` Petr Tesarik
2010-09-03 14:52                                     ` Petr Tesarik
2010-09-03 15:50                                       ` Tony Luck
2010-09-06 14:47                                         ` Petr Tesarik
2010-09-07 13:17                                           ` Petr Tesarik
2010-09-07 17:35                                             ` Tony Luck
2010-09-08 15:55                                               ` Tony Luck
2010-09-10  2:55                                     ` Dave Jones

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=201008272303.34228.ptesarik@suse.cz \
    --to=ptesarik@suse.cz \
    --cc=hedi@sgi.com \
    --cc=linux-ia64@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tony.luck@intel.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