Date: Tue, 12 Aug 2008 04:36:03 -0700
From: Arjan van de Ven <arjan@infradead.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org
Subject: Re: [patch 1/2] fastboot: Add a module parameter to skip probing of
 specific ports
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On Tue, 12 Aug 2008 08:39:03 +0100
Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:

> On Mon, 11 Aug 2008 15:36:41 -0700
> Arjan van de Ven <arjan@infradead.org> wrote:
> 
> > 
> > From: Kristen Accardi <kristen.c.accardi@intel.com>
> > Subject: [PATCH] libata: Add a module parameter to skip probing of
> > specific ports
> > 
> > Port probing by libata can easily take 10% or more of the kernel
> > boot time (2%+ of total). For cases where one knows there is nothing
> > connected to certain ports (for example on netbooks) this is a waste
> > of boot time.
> > 
> > This patch adds a module parameter that allows the admin to specify
> > to skip ports (specified by a bitmask) and recoup this boot time.
> > This capability is potentially also useful to get systems to boot
> > for cases where port-probing on a certain ports causes crashes.
> > 
> > A follow-on patch will add the capability to use DMI identification
> > to automate this for certain known systems.
> 
> What happens if I plug in an additional libata using device ?

on an eeepc ? ;)

at least for the command line option the owner (or whoever sets up
grub) knows the order and could adjust. For the DMI patch you do have a
point.

> What
> defines the probe order here particularly as people are pushing for
> parallel probing of multiple devices.

the patches I'm pushing for this don't change probe order; that has
been tried before and wasn't a great success.


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