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Date: Mon, 1 Feb 2016 08:48:10 -0600
From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Jiri Kosina <jikos@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>, Miroslav Benes <mbenes@suse.cz>,
        Jessica Yu <jeyu@redhat.com>, Seth Jennings <sjenning@redhat.com>,
        Vojtech Pavlik <vojtech@suse.com>, Ingo Molnar <mingo@redhat.com>,
        live-patching@vger.kernel.org, linux-kernel@vger.kernel.org,
        Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [PATCH 1/2] livepatch: Implement separate coming and going
 module notifiers
Message-ID: <20160201144810.GE22854@treble.redhat.com>
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On Mon, Feb 01, 2016 at 01:27:57PM +0100, Jiri Kosina wrote:
> On Fri, 29 Jan 2016, Josh Poimboeuf wrote:
> 
> > Right, as you say it's basically a nop 99.99% of the time.  But we still 
> > need to do the "are any patches loaded" check, so we still need the call 
> > into a livepatch function to do that.
> 
> We might create a static key for that (some might call it 
> over-optimization though, given it's happening on kind of a slow path 
> anyway).

I really don't think that's needed.  Nobody will notice an extra
function call in the module load path.  (And BTW it'll be slightly
faster than today since it doesn't go through the notifier first.)

-- 
Josh