From: Lee Revell <rlrevell@joe-job.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Robert Love <rml@novell.com>
Subject: Re: How is user space notified of CPU speed changes?
Date: Sat, 23 Oct 2004 01:10:37 -0400 [thread overview]
Message-ID: <1098508238.13176.17.camel@krustophenia.net> (raw)
In-Reply-To: <1098444170.19459.7.camel@localhost.localdomain>
On Fri, 2004-10-22 at 12:23 +0100, Alan Cox wrote:
> On Gwe, 2004-10-22 at 00:01, Lee Revell wrote:
> > JACK needs to know the CPU speed, in order to calculate the DSP load
> > among other things. It used to be a valid assumption that you could
> > calculate it on startup and it would not change.
>
> No it did not. It has never been a safe assumption.
OK, thanks. Still no answer to my original question though.
JACK makes extensive use of microsecond-level timers. These must be
calibrated at startup, and recalibrated when the CPU speed changes. How
does JACK register with the kernel to be notified when the CPU speed
changes?
Lee
next prev parent reply other threads:[~2004-10-23 5:15 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-10-21 23:01 How is user space notified of CPU speed changes? Lee Revell
2004-10-22 11:23 ` Alan Cox
2004-10-22 14:12 ` Con Kolivas
2004-10-22 18:05 ` Lee Revell
2004-10-22 18:57 ` Andreas Dilger
2004-10-22 19:40 ` Chris Friesen
2004-10-22 19:46 ` Lee Revell
2004-10-22 20:28 ` Alan Cox
2004-10-22 21:46 ` Chris Friesen
2004-10-22 23:25 ` Lee Revell
2004-10-25 15:28 ` Chris Friesen
2004-10-23 5:10 ` Lee Revell [this message]
2004-10-23 10:53 ` Matthew Garrett
2004-10-23 21:19 ` Alan Cox
2004-10-23 22:42 ` Lee Revell
2004-10-23 23:17 ` Jon Masters
2004-10-24 1:40 ` Lee Revell
2004-10-24 14:02 ` Alan Cox
2004-10-26 2:38 ` Lee Revell
2004-10-26 4:05 ` Lee Revell
2004-10-23 23:35 ` Jon Masters
2004-10-23 23:36 ` Jon Masters
2004-10-24 14:04 ` Alan Cox
2004-10-25 5:53 ` Joel Becker
2004-10-24 20:02 ` Robert Love
[not found] <1098399709.4131.23.camel@krustophenia.net.suse.lists.linux.kernel>
[not found] ` <1098444170.19459.7.camel@localhost.localdomain.suse.lists.linux.kernel>
[not found] ` <1098508238.13176.17.camel@krustophenia.net.suse.lists.linux.kernel>
[not found] ` <1098566366.24804.8.camel@localhost.localdomain.suse.lists.linux.kernel>
2004-10-23 23:54 ` Andi Kleen
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=1098508238.13176.17.camel@krustophenia.net \
--to=rlrevell@joe-job.com \
--cc=alan@lxorguk.ukuu.org.uk \
--cc=linux-kernel@vger.kernel.org \
--cc=rml@novell.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;
as well as URLs for NNTP newsgroup(s).