From: moinejf@free.fr (Jean-Francois Moine)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] of: reduce the number of PROBE_DEFERs
Date: Thu, 22 Aug 2013 10:00:08 +0200 [thread overview]
Message-ID: <20130822100008.2669b0d9@armhf> (raw)
In-Reply-To: <CACxGe6vNKoi47-R3H2sYUhGuX5Lh0nokWaj6Bzw2zv2U0_Wgsg@mail.gmail.com>
On Tue, 20 Aug 2013 11:13:24 +0100
Grant Likely <grant.likely@linaro.org> wrote:
> On Tue, Aug 20, 2013 at 11:01 AM, Jean-Francois Moine <moinejf@free.fr> wrote:
> > This patch populates the platform from the device tree into two steps:
> > the first step creates the nodes that are referenced by a phandle,
> > the second step creates the other nodes.
> >
> > This permits to reduce the number of PROBE_DEFERs.
> >
> > Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
> > ---
> > A better way to reduce probe deferral could be sorting the nodes
> > according to their phandle level in the DT blob at compilation time ...
>
> Have you got measurements or statistics that show this making a
> difference? I suspect you'll find for boot time it will have little to
> no affect since the device driver probe order is more closely related
> to the kernel link order than the order that devices were registered.
With the device tree and most drivers as modules, the kernel link order
does not matter.
I admit that the gain may be small: I just get none or just one probe
deferral instead of 3 on my cubox with this patch.
--
Ken ar c'henta? | ** Breizh ha Linux atav! **
Jef | http://moinejf.free.fr/
WARNING: multiple messages have this Message-ID (diff)
From: Jean-Francois Moine <moinejf@free.fr>
To: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>,
"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] of: reduce the number of PROBE_DEFERs
Date: Thu, 22 Aug 2013 10:00:08 +0200 [thread overview]
Message-ID: <20130822100008.2669b0d9@armhf> (raw)
In-Reply-To: <CACxGe6vNKoi47-R3H2sYUhGuX5Lh0nokWaj6Bzw2zv2U0_Wgsg@mail.gmail.com>
On Tue, 20 Aug 2013 11:13:24 +0100
Grant Likely <grant.likely@linaro.org> wrote:
> On Tue, Aug 20, 2013 at 11:01 AM, Jean-Francois Moine <moinejf@free.fr> wrote:
> > This patch populates the platform from the device tree into two steps:
> > the first step creates the nodes that are referenced by a phandle,
> > the second step creates the other nodes.
> >
> > This permits to reduce the number of PROBE_DEFERs.
> >
> > Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
> > ---
> > A better way to reduce probe deferral could be sorting the nodes
> > according to their phandle level in the DT blob at compilation time ...
>
> Have you got measurements or statistics that show this making a
> difference? I suspect you'll find for boot time it will have little to
> no affect since the device driver probe order is more closely related
> to the kernel link order than the order that devices were registered.
With the device tree and most drivers as modules, the kernel link order
does not matter.
I admit that the gain may be small: I just get none or just one probe
deferral instead of 3 on my cubox with this patch.
--
Ken ar c'hentañ | ** Breizh ha Linux atav! **
Jef | http://moinejf.free.fr/
next prev parent reply other threads:[~2013-08-22 8:00 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-20 10:01 [PATCH] of: reduce the number of PROBE_DEFERs Jean-Francois Moine
2013-08-20 10:01 ` Jean-Francois Moine
2013-08-20 10:13 ` Grant Likely
2013-08-20 10:13 ` Grant Likely
2013-08-22 8:00 ` Jean-Francois Moine [this message]
2013-08-22 8:00 ` Jean-Francois Moine
2013-08-22 10:20 ` Grant Likely
2013-08-22 10:20 ` Grant Likely
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=20130822100008.2669b0d9@armhf \
--to=moinejf@free.fr \
--cc=linux-arm-kernel@lists.infradead.org \
/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.