linux-kernel - Re: [PATCH 00/18] ARM: use const and __initconst for smp

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Message-ID: <20150824212127.GH7557@n2100.arm.linux.org.uk>
Date:	Mon, 24 Aug 2015 22:21:27 +0100
From:	Russell King - ARM Linux <linux@....linux.org.uk>
To:	Olof Johansson <olof@...om.net>
Cc:	Masahiro Yamada <yamada.masahiro@...ionext.com>,
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	"Peter Zijlstra (Intel)" <peterz@...radead.org>
Subject: Re: [PATCH 00/18] ARM: use const and __initconst for smp_operations

On Mon, Aug 24, 2015 at 02:12:06PM -0700, Olof Johansson wrote:
> Easiest of all would probably be to get the sub-arch patches into one
> release, then switch the prototypes and function definitions in the
> next. If you switch prototypes first you'll get a bunch of warnings,
> right?

Wrong way around. :)

If you change the sub-arches to declare the smp operations as const,
and try and pass them into a function which doesn't take a const-pointer,
you'll get a warning.  The core bits need to go in first before the
sub-arch patches.

I think the series has limited value - it allows us to (a) check that a
small quantity of code doesn't write to these things, and (b) allows us
to move the SMP operations structure from __initdata to __initconstdata.
It's still going to end up in the init region which is read/write in any
case, and still gets thrown away.

Given where we are, I don't think we need to rush this in during the
last week before the merge window opens, even though it's trivial.

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