Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754085AbbHHGC5 (ORCPT ); Sat, 8 Aug 2015 02:02:57 -0400 Received: from casper.infradead.org ([85.118.1.10]:54699 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753210AbbHHGC4 (ORCPT ); Sat, 8 Aug 2015 02:02:56 -0400 Date: Sat, 8 Aug 2015 08:02:49 +0200 From: Peter Zijlstra To: Waiman Long Cc: Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org, Scott J Norton , Douglas Hatch , Davidlohr Bueso Subject: Re: [PATCH v5 1/6] locking/pvqspinlock: Unconditional PV kick with _Q_SLOW_VAL Message-ID: <20150808060249.GT16853@twins.programming.kicks-ass.net> References: <1439003881-17349-1-git-send-email-Waiman.Long@hp.com> <1439003881-17349-2-git-send-email-Waiman.Long@hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1439003881-17349-2-git-send-email-Waiman.Long@hp.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 619 Lines: 14 On Fri, Aug 07, 2015 at 11:17:56PM -0400, Waiman Long wrote: > If _Q_SLOW_VAL has been set, the vCPU state must have been vcpu_hashed. > The extra check at the end of __pv_queued_spin_unlock() is unnecessary > and so is removed. This is half the patch it should be. Because if the load is not needed, then the store is not either, and then there's the comments to update. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/