LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Stefan Richter <stefanr@s5r6.in-berlin.de>
To: Pieter Palmers <pieterp@joow.be>
Cc: linux1394-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org
Subject: Re: [RFC] cycle timer read extension for raw1394/libraw1394
Date: Sat, 27 Jan 2007 13:48:51 +0100	[thread overview]
Message-ID: <45BB4A33.4070206@s5r6.in-berlin.de> (raw)
In-Reply-To: <45BB2D67.7030608@joow.be>

Pieter Palmers wrote:
> Stefan Richter wrote:
>> Thus?
>>     preempt_disable();
>>     local_irq_save(flags);
>>
>>     read_cycle_timer;
>>     read_time_of_day;
>>
>>     local_irq_restore(flags);
>>     preempt_enable();
>>
>> in hpsb_read_cycle_timer.
> My main issue was that I still had to figure out how to do this... I'm a
>  very occasional kernel space programmer.

Unfortunately me too, and the level of ieee1394 driver maintenance shows it.

> Thanks for the hint, I'll do it like this.
> 
> I still have to check if I don't introduce a too long non-preemptible
> path though.

It's a simple MMIO read (readl) and the do_gettimeofday, which should be
fine.
-- 
Stefan Richter
-=====-=-=== ---= ==-==
http://arcgraph.de/sr/

  reply	other threads:[~2007-01-27 12:49 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <45BA5CFD.6070900@joow.be>
2007-01-27 10:21 ` Stefan Richter
2007-01-27 10:45   ` Pieter Palmers
2007-01-27 12:48     ` Stefan Richter [this message]
2007-02-03 12:58       ` [PATCH update] ieee1394: " Stefan Richter
2007-02-03 13:42         ` which header for local_irq_save? (was Re: [PATCH update] ieee1394: cycle timer read extension for raw1394/libraw1394) Stefan Richter
2007-02-03 14:22         ` [PATCH update] ieee1394: cycle timer read extension for raw1394/libraw1394 Pieter Palmers
2007-02-03 15:32           ` Stefan Richter
2007-02-04 12:55             ` Pieter Palmers
2007-02-03 16:42         ` Stefan Richter
2007-02-03 19:03         ` Stefan Richter
2007-02-03 20:18           ` Pieter Palmers
2007-02-10 14:20         ` compat_ioctl (was [PATCH update] ieee1394: cycle timer read extension for raw1394/libraw1394) Stefan Richter
2007-02-10 15:47           ` Arnd Bergmann

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=45BB4A33.4070206@s5r6.in-berlin.de \
    --to=stefanr@s5r6.in-berlin.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux1394-devel@lists.sourceforge.net \
    --cc=pieterp@joow.be \
    --subject='Re: [RFC] cycle timer read extension for raw1394/libraw1394' \
    /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).