From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753891AbZIUUKC (ORCPT ); Mon, 21 Sep 2009 16:10:02 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753859AbZIUUKB (ORCPT ); Mon, 21 Sep 2009 16:10:01 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:39172 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753851AbZIUUKA (ORCPT ); Mon, 21 Sep 2009 16:10:00 -0400 Date: Mon, 21 Sep 2009 13:09:41 -0700 From: Andrew Morton To: Ingo Molnar Cc: kilroyd@googlemail.com, a.p.zijlstra@chello.nl, linux-kernel@vger.kernel.org Subject: Re: [patch 1/2] spinlocks: check spinlock_t/rwlock_t argument type on non-SMP builds Message-Id: <20090921130941.e68c4bdb.akpm@linux-foundation.org> In-Reply-To: <20090921074352.GA22122@elte.hu> References: <200909181957.n8IJv94X001996@imap1.linux-foundation.org> <20090921074352.GA22122@elte.hu> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 21 Sep 2009 09:43:52 +0200 Ingo Molnar wrote: > > * akpm@linux-foundation.org wrote: > > > From: David Kilroy > > > > When writing code for UP without CONFIG_DEBUG_SPINLOCK it's easy to get > > the first argument to the spinlock/rwlock functions wrong. This is > > because the parameter is not actually used in this configuration. > > > > Typically you will only find out it's wrong > > * by rebuilding with CONFIG_SMP or CONFIG_DEBUG_SPINLOCK > > * after you've submitted your beautiful patch series. > > > > The first means a long wait, and the latter is a bit late. > > > > Change the intermediate macros into inline functions. > > > > Signed-off-by: David Kilroy > > Cc: Ingo Molnar > > Cc: Peter Zijlstra > > Signed-off-by: Andrew Morton > > --- > > > > include/linux/spinlock.h | 6 - > > include/linux/spinlock_api_up.h | 118 ++++++++++++++++++++++-------- > > 2 files changed, 92 insertions(+), 32 deletions(-) > > > > diff -puN include/linux/spinlock.h~spinlocks-check-spinlock_t-rwlock_t-argument-type-on-non-smp-builds include/linux/spinlock.h > > --- a/include/linux/spinlock.h~spinlocks-check-spinlock_t-rwlock_t-argument-type-on-non-smp-builds > > +++ a/include/linux/spinlock.h > > @@ -240,17 +240,17 @@ static inline void smp_mb__after_lock(vo > > #define spin_lock_irqsave(lock, flags) \ > > do { \ > > typecheck(unsigned long, flags); \ > > - _spin_lock_irqsave(lock, flags); \ > > + _spin_lock_irqsave(lock, &flags); \ > > } while (0) > > #define read_lock_irqsave(lock, flags) \ > > do { \ > > typecheck(unsigned long, flags); \ > > - _read_lock_irqsave(lock, flags); \ > > + _read_lock_irqsave(lock, &flags); \ > > } while (0) > > these bits broke the Alpha build: > > /home/mingo/tip/arch/alpha/include/asm/core_t2.h: In function 't2_readb': > /home/mingo/tip/arch/alpha/include/asm/core_t2.h:451: error: '_spin_lock_irqsave' is static but used in inline function 't2_readb' which is not static hm. What the heck does that mean? __EXTERN_INLINE u8 t2_readb(const volatile void __iomem *xaddr) Something to do with the extern-inline? Do you have the .config? My alpha builds went OK.