Re: [PATCH V3] printk/cache: Mark printk_once test variable __read_mostly

From: Tony Luck <tony.luck@gmail.com>
To: Joe Perches <joe@perches.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	James Hogan <james.hogan@imgtec.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	"linux-next@vger.kernel.org" <linux-next@vger.kernel.org>,
	linux-metag@vger.kernel.org
Subject: Re: [PATCH V3] printk/cache: Mark printk_once test variable __read_mostly
Date: Tue, 12 Nov 2013 16:23:19 -0800	[thread overview]
Message-ID: <CA+8MBb+rrAWSTTvO4cx32ju-QOAG6aHHxR9B=sLtGXR3q8DF0A@mail.gmail.com> (raw)
In-Reply-To: <1383244173.8740.9.camel@joe-AO722>

Trying this again with HTML disabled in gmail so mailing lists will see it ...

On Thu, Oct 31, 2013 at 11:29 AM, Joe Perches <joe@perches.com> wrote:
> diff --git a/include/linux/cache.h b/include/linux/cache.h
> index 4c57065..17e7e82 100644
> --- a/include/linux/cache.h
> +++ b/include/linux/cache.h
> @@ -1,11 +1,11 @@
>  #ifndef __LINUX_CACHE_H
>  #define __LINUX_CACHE_H
>
> -#include <linux/kernel.h>
> +#include <uapi/linux/kernel.h>
>  #include <asm/cache.h>

This bit seems to be responsible for breaking the ia64 build
in today's linux-next (tag: next-20131112)

Compiler barfs at:
   CC      arch/ia64/kernel/patch.o
In file included from arch/ia64/kernel/patch.c:12:
/home/aegl/zx1-smp/arch/ia64/include/asm/processor.h: In function
‘ia64_get_irr’:
/home/aegl/zx1-smp/arch/ia64/include/asm/processor.h:565: error:
implicit declaration of function ‘test_bit’
In file included from include/linux/bitops.h:33,
                 from include/linux/kernel.h:10,
                 from include/asm-generic/bug.h:13,
                 from /home/aegl/zx1-smp/arch/ia64/include/asm/bug.h:12,
                 from include/linux/bug.h:4,
                 from include/linux/thread_info.h:11,
                 from include/asm-generic/preempt.h:4,
                 from arch/ia64/include/generated/asm/preempt.h:1,
                 from include/linux/preempt.h:18,
                 from include/linux/uaccess.h:4,
                 from /home/aegl/zx1-smp/arch/ia64/include/asm/sections.h:10,
                 from arch/ia64/kernel/patch.c:13:
/home/aegl/zx1-smp/arch/ia64/include/asm/bitops.h: At top level:
/home/aegl/zx1-smp/arch/ia64/include/asm/bitops.h:339: error: static
declaration of ‘test_bit’ follows non-static declaration
/home/aegl/zx1-smp/arch/ia64/include/asm/processor.h:565: error:
previous implicit declaration of ‘test_bit’ was here
make[1]: *** [arch/ia64/kernel/patch.o] Error 1
make: *** [arch/ia64/kernel/patch.o] Error 2

Other files choke in the similar way because they no longer implicitly
get <linux/kernel.h>
(and all the other files that pulls in). Just backing out that one
line of diff fixes it for me.
But presumably is a problem someplace else given the "avoid recursive #includes"
bit of the commit message.

-Tony