From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756659AbZIDG6R (ORCPT ); Fri, 4 Sep 2009 02:58:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755647AbZIDG6Q (ORCPT ); Fri, 4 Sep 2009 02:58:16 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:41150 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755460AbZIDG6P (ORCPT ); Fri, 4 Sep 2009 02:58:15 -0400 Date: Fri, 4 Sep 2009 08:57:45 +0200 From: Ingo Molnar To: Catalin Marinas Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Ingo Molnar Subject: Re: [PATCH 1/2] kmemleak: Inform kmemleak about kernel stack allocation Message-ID: <20090904065745.GE29829@elte.hu> References: <20090827165927.27901.97270.stgit@pc1117.cambridge.arm.com> <20090827170253.27901.33997.stgit@pc1117.cambridge.arm.com> <20090829132954.GB24123@elte.hu> <1251556083.5518.2.camel@pc1117.cambridge.arm.com> <20090831084546.GE15619@elte.hu> <1251797114.10349.28.camel@pc1117.cambridge.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1251797114.10349.28.camel@pc1117.cambridge.arm.com> 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 * Catalin Marinas wrote: > On Mon, 2009-08-31 at 10:45 +0200, Ingo Molnar wrote: > > * Catalin Marinas wrote: > > > > > On Sat, 2009-08-29 at 15:29 +0200, Ingo Molnar wrote: > > > > * Catalin Marinas wrote: > [...] > > > > > diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h > > > > > index fad7d40..f26432a 100644 > > > > > --- a/arch/x86/include/asm/thread_info.h > > > > > +++ b/arch/x86/include/asm/thread_info.h > > > > > @@ -162,7 +162,12 @@ struct thread_info { > > > > > #define __HAVE_ARCH_THREAD_INFO_ALLOCATOR > > > > > > > > > > #define alloc_thread_info(tsk) \ > > > > > - ((struct thread_info *)__get_free_pages(THREAD_FLAGS, THREAD_ORDER)) > > > > > +({ \ > > > > > + struct thread_info *ti = (struct thread_info *) \ > > > > > + __get_free_pages(THREAD_FLAGS, THREAD_ORDER); \ > > > > > + kmemleak_alloc(ti, THREAD_SIZE, 1, THREAD_FLAGS); \ > > > > > + ti; \ > > > > > +}) > > > > > > > > Sidenote:this used to be a trivial wrapper to gfp so it was > > > > borderline OK as a CPP macro - now it's a non-trivial CPP wrapper > > > > macro which is not OK. Mind converting it to an inline function? > > > > > > I tried this first but got compilation errors in files that didn't > > > even call this function. To make it workable, thread_info.h would > > > need to include additional headers. If that's acceptable, I can > > > post an updated patch. > > > > I havent tried the patch myself, but by your description those build > > problems seem to be pre-existing include file dependency problems > > that should be tracked down and resolved - instead of widening them > > by adding even more hidden dependencies via CPP macros. > > I tried to move to an inline function and linux/gfp.h is needed for > __get_free_pages() and GFP_* macros. This leads to some complicated > circular dependencies like below: > > CC arch/x86/kernel/asm-offsets.s > In file included from /work/Linux/2.6/linux-2.6-arm/include/linux/mmzone.h:9, > from /work/Linux/2.6/linux-2.6-arm/include/linux/gfp.h:4, > from /work/Linux/2.6/linux-2.6-arm/arch/x86/include/asm/thread_info.h:22, > from /work/Linux/2.6/linux-2.6-arm/include/linux/thread_info.h:56, > from /work/Linux/2.6/linux-2.6-arm/include/linux/preempt.h:9, > from /work/Linux/2.6/linux-2.6-arm/include/linux/spinlock.h:50, > from /work/Linux/2.6/linux-2.6-arm/include/linux/seqlock.h:29, > from /work/Linux/2.6/linux-2.6-arm/include/linux/time.h:8, > from /work/Linux/2.6/linux-2.6-arm/include/linux/stat.h:60, > from /work/Linux/2.6/linux-2.6-arm/include/linux/module.h:10, > from /work/Linux/2.6/linux-2.6-arm/include/linux/crypto.h:21, > from /work/Linux/2.6/linux-2.6-arm/arch/x86/kernel/asm-offsets_32.c:7, > from /work/Linux/2.6/linux-2.6-arm/arch/x86/kernel/asm-offsets.c:2: > include/linux/wait.h|51| error: expected specifier-qualifier-list before ???spinlock_t??? > > The linux/mmzone.h file normally includes linux/spinlock.h but the > reverse is also true when the latter includes the former via > thread_info.h and gfp.h. Because of the (correct) guards in the > header files, the spinlock_t definition is no longer available in > mmzone.h. mmzone.h probably should not include spinlock.h (which is heavy) - it should include spinlock_types.h (which is lighter). It only needs the type definitions and none of the API definitions. Ingo