Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759310AbcJQU2S (ORCPT ); Mon, 17 Oct 2016 16:28:18 -0400 Received: from mail-by2nam01on0064.outbound.protection.outlook.com ([104.47.34.64]:5984 "EHLO NAM01-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757730AbcJQU2I (ORCPT ); Mon, 17 Oct 2016 16:28:08 -0400 Authentication-Results: spf=pass (sender IP is 63.163.107.225) smtp.mailfrom=sandisk.com; vger.kernel.org; dkim=none (message not signed) header.d=none;vger.kernel.org; dmarc=bestguesspass action=none header.from=sandisk.com; X-AuditID: 0ac94371-5f3ff7000000f08d-b0-580532197af5 Subject: Re: [PATCH 0/8] infiniband: Remove semaphores To: Arnd Bergmann References: <1476721862-7070-1-git-send-email-binoy.jayan@linaro.org> <216461f1-3070-c93a-a560-7560a727cb8d@sandisk.com> <6244597.a6XMUIxjP0@wuerfel> CC: Binoy Jayan , Doug Ledford , Sean Hefty , Hal Rosenstock , "linux-rdma@vger.kernel.org" , "linux-kernel@vger.kernel.org" From: Bart Van Assche Message-ID: <8c560960-5498-57b5-6da6-218b71d9eef9@sandisk.com> Date: Mon, 17 Oct 2016 13:28:01 -0700 User-Agent: Mozilla/5.0 (X11; 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I haven't looked at drivers/infiniband/ > yet for this, but I believe that drivers/acpi/ is a case for > which I see no better alternative (the AML bytecode requires > counting semaphore semantics). Hello Arnd, Thanks for the detailed reply. However, I doubt that removing and open-coding counting semaphores is the best alternative. Counting semaphores are a useful abstraction. I think open-coding counting semaphores everywhere counting semaphores are used would be a step back instead of a step forward. Bart.