From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754725AbcHSQWP (ORCPT ); Fri, 19 Aug 2016 12:22:15 -0400 Received: from mail-co1nam03on0138.outbound.protection.outlook.com ([104.47.40.138]:35280 "EHLO NAM03-CO1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753990AbcHSQWN (ORCPT ); Fri, 19 Aug 2016 12:22:13 -0400 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=waiman.long@hpe.com; Message-ID: <57B73225.7020303@hpe.com> Date: Fri, 19 Aug 2016 12:21:57 -0400 From: Waiman Long User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.12) Gecko/20130109 Thunderbird/10.0.12 MIME-Version: 1.0 To: Wanpeng Li CC: Peter Zijlstra , Ingo Molnar , "linux-kernel@vger.kernel.org" , the arch/x86 maintainers , , , linux-s390 , , , Davidlohr Bueso , Jason Low , Dave Chinner , Jonathan Corbet , Scott J Norton , Douglas Hatch Subject: Re: [RFC PATCH-tip v4 07/10] locking/rwsem: Change RWSEM_WAITING_BIAS for better disambiguation References: <1471554672-38662-1-git-send-email-Waiman.Long@hpe.com> <1471554672-38662-8-git-send-email-Waiman.Long@hpe.com> In-Reply-To: Content-Type: text/plain; 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There is no easy way to > count = 0xffff000X > > However, RWSEM_WAITING_BIAS is equal to 0xffff0000, so both these two > cases are beyond RWSEM_WAITING_BIAS, right? > > Regards, > Wanpeng Li Perhaps I should make it clear that I am talking from a signed quantity point of view (it is an atomic_long_t). So RWSEM_WAITING_BIAS < RWSEM_ACTIVE_WRITE_BIAS < 0 Hope this clarify your question. Cheers, Longman