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Date: Fri, 13 May 2011 14:26:46 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 3/5] v2 seccomp_filters: Enable ftrace-based system call
	filtering
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Cc: linux-mips@linux-mips.org, linux-sh@vger.kernel.org,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Oleg Nesterov <oleg@redhat.com>, David Howells <dhowells@redhat.com>,
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* Peter Zijlstra <peterz@infradead.org> wrote:

> On Fri, 2011-05-13 at 14:10 +0200, Ingo Molnar wrote:
> >         err = event_vfs_getname(result);
> 
> I really think we should not do this. Events like we have them should be 
> inactive, totally passive entities, only observe but not affect execution 
> (other than the bare minimal time delay introduced by observance).

Well, this patchset already demonstrates that we can use a single event 
callback for a rather useful purpose.

Either it makes sense to do, in which case we should share facilities as much 
as possible, or it makes no sense, in which case we should not merge it at all.

> If you want another entity that is more active, please invent a new name for 
> it and create a new subsystem for them, now you could have these active 
> entities also have an (automatic) passive event side, but that's some detail.

Why should we have two callbacks next to each other:

	event_vfs_getname(result);
	result = check_event_vfs_getname(result);

if one could do it all?

Thanks,

	Ingo