All of lore.kernel.org
 help / color / mirror / Atom feed
From: Ingo Molnar <mingo@elte.hu>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: john stultz <johnstul@us.ibm.com>,
	tglx@linutronix.de, linux-kernel@vger.kernel.org
Subject: Re: Ktimer / -rt9 (+custom) monotonic_clock going backwards.
Date: Thu, 20 Oct 2005 17:55:25 +0200	[thread overview]
Message-ID: <20051020155525.GA10360@elte.hu> (raw)
In-Reply-To: <Pine.LNX.4.58.0510200605170.27683@localhost.localdomain>


* Steven Rostedt <rostedt@goodmis.org> wrote:

> > I just switched cycle_t to u64 and hackbench no longer makes the time go
> > backwards.
> >
> > John, would this cause any problems to keep cycle_t at s64?
> 
> I mean at u64.

ugh. There's both cycles_t and cycle_t. We should unify the two and it 
should be 64-bit. The faster systems get, the sooner the 32-bit counter 
overflows. 64-bit systems are keeping 32-bit compatibility for quite 
some time to come. So with an 8GHz CPU the 32-bit cycle_t would wrap in 
like 500 msecs, way too fast to rely on ... (even with a 4GHz CPUs it's 
only one second.)

i've made cycle_t u64 and have uploaded -rt14.

	Ingo

  reply	other threads:[~2005-10-20 15:55 UTC|newest]

Thread overview: 44+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-10-19 14:59 Ktimer / -rt9 (+custom) monotonic_clock going backwards Steven Rostedt
2005-10-19 15:10 ` Thomas Gleixner
2005-10-19 18:39   ` john stultz
2005-10-20  6:55     ` Steven Rostedt
2005-10-20  7:34       ` Ingo Molnar
2005-10-20  7:46         ` Steven Rostedt
2005-10-20  8:01           ` Ingo Molnar
2005-10-20  8:56             ` Steven Rostedt
2005-10-20  8:59               ` Ingo Molnar
2005-10-20  9:04                 ` Steven Rostedt
2005-10-20  9:05                   ` Steven Rostedt
2005-10-20 10:05                   ` Steven Rostedt
2005-10-20 10:05                     ` Steven Rostedt
2005-10-20 15:55                       ` Ingo Molnar [this message]
2005-10-20 16:09                         ` Steven Rostedt
2005-10-20 16:45                       ` john stultz
2005-10-20 16:58                         ` Steven Rostedt
2005-10-20 17:05                           ` john stultz
2005-10-20 19:32                         ` Ingo Molnar
2005-10-20 20:05                           ` john stultz
2005-10-20 20:54                             ` Ingo Molnar
2005-10-21  6:03                           ` Steven Rostedt
2005-10-21  7:49                             ` Thomas Gleixner
2005-10-21  7:57                               ` Steven Rostedt
2005-10-21  8:00                               ` ktimer API Steven Rostedt
2005-10-21  8:09                                 ` Thomas Gleixner
2005-10-21 18:09                             ` Ktimer / -rt9 (+custom) monotonic_clock going backwards john stultz
2005-10-21 18:15                               ` Thomas Gleixner
2005-10-20 22:06           ` George Anzinger
2005-10-20  6:19   ` Steven Rostedt
2005-10-20 14:34   ` Steven Rostedt
2005-10-20 15:18     ` Steven Rostedt
2005-10-20 15:23       ` Steven Rostedt
2005-10-20 16:01       ` Steven Rostedt
2005-10-19 15:11 ` Ingo Molnar
2005-10-20  6:38   ` Steven Rostedt
2005-10-20  6:56     ` Ingo Molnar
2005-10-19 15:21 ` Daniel Walker
2005-10-20  6:39   ` Steven Rostedt
2005-10-20 15:02     ` Daniel Walker
2005-10-20 22:19       ` George Anzinger
2005-10-20 23:23         ` john stultz
2005-10-19 16:44 ` Frank Sorenson
2005-10-20  6:43   ` Steven Rostedt

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=20051020155525.GA10360@elte.hu \
    --to=mingo@elte.hu \
    --cc=johnstul@us.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=rostedt@goodmis.org \
    --cc=tglx@linutronix.de \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.