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Date: Sun, 16 Apr 2006 16:03:59 +0200
From: Sam Ravnborg <sam@ravnborg.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>, Nick Piggin <nickpiggin@yahoo.com.au>,
       LKML <linux-kernel@vger.kernel.org>, Andrew Morton <akpm@osdl.org>,
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Subject: Re: [PATCH 00/05] robust per_cpu allocation for modules
Message-ID: <20060416140359.GA15091@mars.ravnborg.org>
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On Sun, Apr 16, 2006 at 09:40:04AM -0400, Steven Rostedt wrote:
 
> The per_cpu variables are defined with the macro 
>     DEFINE_PER_CPU(type, var)
> 
> This macro just places the variable into the section .data.percpu and
> prepends the prefix "per_cpu__" to the variable.
> 
> To use this variable in another .c file the declaration is used by the
> macro
>     DECLARE_PER_CPU(type, var)
> 
> This macro is simply the extern declaration of the variable with the
> prefix added.
Suprisingly this macro shows up in ~19 .c files. Only valid usage is
forward declaration of a later static definition with DEFINE_PER_CPU.
arch/m32r/kernel/smp.c + arch/m32r/kernel/smpboot.c is jsut one example.

Just a random comment not related to Steven's patches.

	Sam