From mboxrd@z Thu Jan 1 00:00:00 1970 From: Waiman Long Subject: Re: [PATCH v10 07/19] qspinlock: Use a simple write to grab the lock, if applicable Date: Fri, 09 May 2014 21:06:08 -0400 Message-ID: <536D7B80.7080301@hp.com> References: <1399474907-22206-1-git-send-email-Waiman.Long@hp.com> <1399474907-22206-8-git-send-email-Waiman.Long@hp.com> <20140508190203.GP2844@laptop.programming.kicks-ass.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140508190203.GP2844@laptop.programming.kicks-ass.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Peter Zijlstra Cc: linux-arch@vger.kernel.org, Rik van Riel , Raghavendra K T , Oleg Nesterov , Gleb Natapov , kvm@vger.kernel.org, Konrad Rzeszutek Wilk , Scott J Norton , x86@kernel.org, Paolo Bonzini , linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, Ingo Molnar , Chegu Vinod , David Vrabel , "H. Peter Anvin" , xen-devel@lists.xenproject.org, Thomas Gleixner , "Paul E. McKenney" , Linus Torvalds , Boris Ostrovsky List-Id: linux-arch.vger.kernel.org On 05/08/2014 03:02 PM, Peter Zijlstra wrote: > On Wed, May 07, 2014 at 11:01:35AM -0400, Waiman Long wrote: >> /** >> + * get_qlock - Set the lock bit and own the lock >> + * @lock: Pointer to queue spinlock structure >> + * >> + * This routine should only be called when the caller is the only one >> + * entitled to acquire the lock. >> + */ >> +static __always_inline void get_qlock(struct qspinlock *lock) > set_locked() > >> +{ >> + struct __qspinlock *l = (void *)lock; >> + >> + barrier(); >> + ACCESS_ONCE(l->locked) = _Q_LOCKED_VAL; >> + barrier(); >> +} > get_qlock() is just horrible. The function doesn't actually _get_ > anything, and qlock is not in line with the rest of the naming. Sure, I will make the change. -Longman From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from g6t1525.atlanta.hp.com ([15.193.200.68]:56400 "EHLO g6t1525.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757281AbaEJBGb (ORCPT ); Fri, 9 May 2014 21:06:31 -0400 Message-ID: <536D7B80.7080301@hp.com> Date: Fri, 09 May 2014 21:06:08 -0400 From: Waiman Long MIME-Version: 1.0 Subject: Re: [PATCH v10 07/19] qspinlock: Use a simple write to grab the lock, if applicable References: <1399474907-22206-1-git-send-email-Waiman.Long@hp.com> <1399474907-22206-8-git-send-email-Waiman.Long@hp.com> <20140508190203.GP2844@laptop.programming.kicks-ass.net> In-Reply-To: <20140508190203.GP2844@laptop.programming.kicks-ass.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-arch-owner@vger.kernel.org List-ID: To: Peter Zijlstra Cc: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , linux-arch@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, xen-devel@lists.xenproject.org, kvm@vger.kernel.org, Paolo Bonzini , Konrad Rzeszutek Wilk , Boris Ostrovsky , "Paul E. McKenney" , Rik van Riel , Linus Torvalds , Raghavendra K T , David Vrabel , Oleg Nesterov , Gleb Natapov , Scott J Norton , Chegu Vinod Message-ID: <20140510010608.nwTAjSdr8l49CgLASnusL-vMbUVVhC63jWwLuWDmpRc@z> On 05/08/2014 03:02 PM, Peter Zijlstra wrote: > On Wed, May 07, 2014 at 11:01:35AM -0400, Waiman Long wrote: >> /** >> + * get_qlock - Set the lock bit and own the lock >> + * @lock: Pointer to queue spinlock structure >> + * >> + * This routine should only be called when the caller is the only one >> + * entitled to acquire the lock. >> + */ >> +static __always_inline void get_qlock(struct qspinlock *lock) > set_locked() > >> +{ >> + struct __qspinlock *l = (void *)lock; >> + >> + barrier(); >> + ACCESS_ONCE(l->locked) = _Q_LOCKED_VAL; >> + barrier(); >> +} > get_qlock() is just horrible. The function doesn't actually _get_ > anything, and qlock is not in line with the rest of the naming. Sure, I will make the change. -Longman