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[23.128.96.18]) by mx.google.com with ESMTP id e18si1757199eje.132.2020.11.20.06.47.05; Fri, 20 Nov 2020 06:47:28 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@infradead.org header.s=merlin.20170209 header.b=c4dNfBjh; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727829AbgKTOmm (ORCPT + 99 others); Fri, 20 Nov 2020 09:42:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726490AbgKTOml (ORCPT ); Fri, 20 Nov 2020 09:42:41 -0500 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A51FC0613CF for ; Fri, 20 Nov 2020 06:42:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=jVVtcjI2KBzyw6L6PWdDe5VqbWBRupAvsWfUE9BVLRQ=; b=c4dNfBjhdRiFc0MXiW7Q7KwEcp Vb1AWraq53XJErBgB5B1BVl/IMPDEptQa88U/6eboiqIMd/+mGXe8DLRdBbeTqN0STFv85sjyKkzz Pw7wUyFbbz6H23bwkNoLbxB2i9csNsy3wHy1IYyUV62oRwwK09Sm3RuOUwo4QWeFOk6wGSzSHPVTd glHPCArEDg9TIhJE/uQmJNCc9AHykIxIUSOaSifUC4e04oGc08oF7mxlo8VmtUafxBK/Uh4lNOlkv yba881xfF6CeqyFI6vWvcQi/DuJ3i+CB4ple9ppR6iWy8h8msc20Tjwo4lgvKY4ET3vDK4KyfMoHj ICdeENfQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kg7cQ-0005Py-Nj; Fri, 20 Nov 2020 14:42:34 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 095BF305C16; Fri, 20 Nov 2020 15:42:33 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id E9CCC201B4C4C; Fri, 20 Nov 2020 15:42:32 +0100 (CET) Date: Fri, 20 Nov 2020 15:42:32 +0100 From: Peter Zijlstra To: Waiman Long Cc: Ingo Molnar , Will Deacon , linux-kernel@vger.kernel.org, Davidlohr Bueso , Phil Auld Subject: Re: [RFC PATCH 5/5] locking/rwsem: Remove reader optimistic spinning Message-ID: <20201120144232.GE3040@hirez.programming.kicks-ass.net> References: <20201118030429.23017-1-longman@redhat.com> <20201118030429.23017-6-longman@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201118030429.23017-6-longman@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 17, 2020 at 10:04:29PM -0500, Waiman Long wrote: > -static inline bool osq_is_empty(struct rw_semaphore *sem) > -{ > - return !osq_is_locked(&sem->osq); > -static inline bool osq_is_empty(sem) > -{ > - return false; > -} Oh, it doesn't live...