Re: [GIT PULL 3/6] ARM: SoC driver updates for 5.1 - Russell King

From: Russell King - ARM Linux admin <linux@armlinux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>,
	soc@kernel.org, Linux ARM <linux-arm-kernel@lists.infradead.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	arm-soc <arm@kernel.org>
Subject: Re: [GIT PULL 3/6] ARM: SoC driver updates for 5.1
Date: Wed, 6 Mar 2019 18:15:57 +0000	[thread overview]
Message-ID: <20190306181557.fndmy5oks3sximeo@shell.armlinux.org.uk> (raw)
In-Reply-To: <CAHk-=wgdJKaDt=Dp_DS+LL3bzRZUo2VHHMZU_VUMukSPzRJPUw@mail.gmail.com>

On Wed, Mar 06, 2019 at 10:09:28AM -0800, Linus Torvalds wrote:
> On Wed, Mar 6, 2019 at 7:34 AM Arnd Bergmann <arnd@arndb.de> wrote:
> >
> >   git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git tags/armsoc-drivers
> 
> This caused a surprising number of kernel file rebuilds for me, and
> the reason was
> 
> >  include/linux/mod_devicetable.h                                     |   9 +
> 
> It turns out that the above is indirectly included from a _lot_ of
> code device header files.
> 
> The reason seems to be the various 'struct *_device_id' declarations,
> that then all the different header files want.
> 
> So a tiny change in an oddball header file causes a lot of recompiles.
> 
> Oh well. I don't know if there is anything to be done, but I did react
> to how some surprising changes cause a lot of build activity, and it's
> not always obvious.

Would it be worth splitting up mod_devicetable.h and having drivers
include just the bus-specific device table header(s) that the driver
requires?

-- 
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