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Date: Mon, 23 Apr 2012 23:25:36 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>, Ingo Molnar <mingo@elte.hu>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
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        Jim Keniston <jkenisto@linux.vnet.ibm.com>,
        LKML <linux-kernel@vger.kernel.org>, Linux-mm <linux-mm@kvack.org>,
        Andi Kleen <andi@firstfloor.org>,
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        Steven Rostedt <rostedt@goodmis.org>,
        Arnaldo Carvalho de Melo <acme@infradead.org>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Thomas Gleixner <tglx@linutronix.de>, Anton Arapov <anton@redhat.com>
Subject: Re: [RFC 0/6] uprobes: kill uprobes_srcu/uprobe_srcu_id
Message-ID: <20120423212536.GA8700@redhat.com>
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forgot to mention,

On 04/23, Oleg Nesterov wrote:
>
> Just it seems to me there are to many "details"
> we should discuss to make the filtering reasonable.

And so far we assumed that consumer->filter() is "stable" and never
changes its mind.

Perhaps this is fine, but I am not sure. May we need need some
interface to add/del the task. Probably not, but unregister + register
doesn't look very convenient and can miss a hit.

> Yes, and probably this makes sense for handler_chain(). Although otoh
> I do not really understand what this filter buys us at this point.

But if we change the rules so that ->filter() or ->handler() itself can
return the "please remove this bp from ->mm" then perhaps it makes more
sense for the filtering. Again, not sure.

Oleg.