[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Tue, 07 Aug 2007 21:15:12 -0700
From: Arjan van de Ven <arjan@...radead.org>
To: Roman Zippel <zippel@...ux-m68k.org>
Cc: Jonathan Corbet <corbet@....net>, linux-kernel@...r.kernel.org,
Thomas Gleixner <tglx@...utronix.de>,
akpm@...ux-foundation.org, Ingo Molnar <mingo@...e.hu>
Subject: Re: [PATCH] msleep() with hrtimers
On Tue, 2007-08-07 at 14:45 +0200, Roman Zippel wrote:
> Hi,
>
> On Mon, 6 Aug 2007, Arjan van de Ven wrote:
>
> > So, let me ask a direct question: What do you think is specifically
> > wrong about changing the msleep() implementation as is done here? The
> > behavior is clearly an improvement, so what is your objection on the
> > flipside?
>
> Again, we have two different timer APIs for a reason
yes because we have different usage patterns for timers. (exact/course
or expiring/not-typically-expiring; I know you have some other opinion
here than other people).
For this case it's relatively simple imo: The existing implementation
has a *typical* behavior which is 100% to 2000% worse than what the user
of the API asks for. And that is totally unneeded to be so crappy; it
can be much more exact easily as shown by this patch.
You keep claiming that hrtimers are so incredibly expensive; but for
msleep()... which is mostly called during driver init ... I really don't
buy that it's really expensive. We're not doing this a gazilion times
per second obviously...
--
if you want to mail me at work (you don't), use arjan (at) linux.intel.com
Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists