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Date: Wed, 23 Jun 2010 12:37:44 +0200
From: Andi Kleen <ak@linux.intel.com>
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To: Frederic Weisbecker <fweisbec@gmail.com>
Subject: Re: [PATCH 31/40] trace syscalls: Convert various generic compat
	syscalls
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Cc: Christoph Lameter <cl@linux-foundation.org>, WANG Cong <amwang@redhat.com>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Oleg Nesterov <oleg@redhat.com>, linuxppc-dev@ozlabs.org,
	Paul Mackerras <paulus@samba.org>, "H. Peter Anvin" <hpa@zytor.com>,
	Sam Ravnborg <sam@ravnborg.org>, Mike Frysinger <vapier.adi@gmail.com>,
	Eric Dumazet <eric.dumazet@gmail.com>,
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	David Rientjes <rientjes@google.com>,
	Ingo Molnar <mingo@elte.hu>, Arnd Bergmann <arnd@arndb.de>,
	Steven Rostedt <rostedt@goodmis.org>, Ian Munsie <imunsie@au1.ibm.com>,
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	netdev@vger.kernel.org, Jason Baron <jbaron@redhat.com>,
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, Frederic Weisbecker wrote:
> On Wed, Jun 23, 2010 at 12:19:38PM +0200, Andi Kleen wrote:
>> , Ian Munsie wrote:
>>> From: Ian Munsie<imunsie@au1.ibm.com>
>>>
>>> This patch converts numerous trivial compat syscalls through the generic
>>> kernel code to use the COMPAT_SYSCALL_DEFINE family of macros.
>>
>> Why? This just makes the code look uglier and the functions harder
>> to grep for.
>
>
> Because it makes them usable with syscall tracing.

Ok that information is missing in the changelog then.

Also I hope the uglification<->usefullness factor is really worth it.
The patch is certainly no slouch on the uglification side.

It also has maintenance costs, e.g. I doubt ctags and cscope
will be able to deal with these kinds of macros, so it has a
high cost for everyone using these tools. For those
it would be actually better if you used separate annotation
that does not confuse standard C parsers.

-Andi