From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756324AbZFTQZ1 (ORCPT ); Sat, 20 Jun 2009 12:25:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751383AbZFTQZQ (ORCPT ); Sat, 20 Jun 2009 12:25:16 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:50145 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751229AbZFTQZP (ORCPT ); Sat, 20 Jun 2009 12:25:15 -0400 Date: Sat, 20 Jun 2009 18:25:13 +0200 From: Ingo Molnar To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Andrew Morton , Frederic Weisbecker Subject: Re: [PATCH 1/2] function-graph: disable when both x86_32 and optimize for size are configured Message-ID: <20090620162513.GD32377@elte.hu> References: <20090618224409.916725341@goodmis.org> <20090618225248.476090968@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090618225248.476090968@goodmis.org> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Steven Rostedt wrote: > diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig > index 4a13e5a..1eac852 100644 > --- a/kernel/trace/Kconfig > +++ b/kernel/trace/Kconfig > @@ -121,6 +121,7 @@ config FUNCTION_GRAPH_TRACER > bool "Kernel Function Graph Tracer" > depends on HAVE_FUNCTION_GRAPH_TRACER > depends on FUNCTION_TRACER > + depends on !X86_32 || !CC_OPTIMIZE_FOR_SIZE > default y Hm, nice fix, but this is a quite nasty constraint - distros like to enable CC_OPTIMIZE_FOR_SIZE as it neatly trims the kernel's size by about 30%. Just in case you have not checked yet: is there no way to turn off the specific gcc optimization that causes this? Or is it -Os itself that does this optimization? Ingo