From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from toip3.srvr.bell.ca ([209.226.175.86]) by tomts16-srv.bellnexxia.net (InterMail vM.5.01.06.13 201-253-122-130-113-20050324) with ESMTP id <20080811182939.FPML1723.tomts16-srv.bellnexxia.net@toip3.srvr.bell.ca> for ; Mon, 11 Aug 2008 14:29:39 -0400 Date: Mon, 11 Aug 2008 14:29:38 -0400 From: Mathieu Desnoyers Subject: Re: [PATCH 4/5] kmemtrace: SLUB hooks. Message-ID: <20080811182938.GD32207@Krystal> References: <1218388447-5578-1-git-send-email-eduard.munteanu@linux360.ro> <1218388447-5578-2-git-send-email-eduard.munteanu@linux360.ro> <1218388447-5578-3-git-send-email-eduard.munteanu@linux360.ro> <1218388447-5578-4-git-send-email-eduard.munteanu@linux360.ro> <1218388447-5578-5-git-send-email-eduard.munteanu@linux360.ro> <48A046F5.2000505@linux-foundation.org> <1218463774.7813.291.camel@penberg-laptop> <48A048FD.30909@linux-foundation.org> <48A04EC2.1080302@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <48A04EC2.1080302@linux-foundation.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: Steven Rostedt , Pekka Enberg , Eduard - Gabriel Munteanu , linux-mm@kvack.org, linux-kernel@vger.kernel.org, rdunlap@xenotime.net, mpm@selenic.com, tglx@linutronix.de List-ID: * Christoph Lameter (cl@linux-foundation.org) wrote: > Steven Rostedt wrote: > > > The kmemtrace_mark_alloc_node itself is an inline function, which calls > > another inline function "trace_mark" which is designed to test a > > read_mostly variable, and will do an "unlikely" jmp if the variable is > > set (which it is when tracing is enabled), to the actual function call. > > > > There should be no extra function calls when this is configured on but > > tracing disabled. We try very hard to keep the speed of the tracer as > > close to a non tracing kernel as possible when tracing is disabled. > > Makes sense. But then we have even more code bloat because of the tests that > are inserted in all call sites of kmalloc. > The long-term goal is to turn the tests into NOPs, but only once we get gcc support. Mathieu -- Mathieu Desnoyers OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org