From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0217EC04EB8 for ; Mon, 10 Dec 2018 21:44:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB8772084E for ; Mon, 10 Dec 2018 21:44:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="iXyAFh3E" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BB8772084E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.dk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-block-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727757AbeLJVon (ORCPT ); Mon, 10 Dec 2018 16:44:43 -0500 Received: from mail-pg1-f193.google.com ([209.85.215.193]:39696 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727716AbeLJVom (ORCPT ); Mon, 10 Dec 2018 16:44:42 -0500 Received: by mail-pg1-f193.google.com with SMTP id w6so5582546pgl.6 for ; Mon, 10 Dec 2018 13:44:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=Q/LNkITI6Mo00J9iVRX70fKCzr1sV4kHJirNir7Hw5E=; b=iXyAFh3E3oigxUa5uYeSGAQCGcrf13cPQEJBqIBuI9upstTBdM5bP2igSIoanHfjv2 XZhpulwOxUuNq+Z5B2ZOQ6peURFOeItO3fOgBcjrN/4KwlHVHfgKG9YmAI0J6MabzxVg LKoags1R4zDMIxOkBWiBM18Vya7OdqSXHu1gJ2qtxTHxmMkxkWIyS7GxNA8HV4liqXPL SVKOtcr3EUlmJjYiZkNQnyAOmvSCpKZJ38o4Ee/X8OTDY+o9+BQ3svPe0cHYP1sYK/H8 yYIKit/AoJ26+6d6teoCtl0I+mQowr3x0infaTdR7KAVXuRWGbWEpOslqdMZB25rGfq9 bxuQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Q/LNkITI6Mo00J9iVRX70fKCzr1sV4kHJirNir7Hw5E=; b=Jfy3banC2HiJsrDNJ0odDL+aFXk2AN2hHwuiRnJYgdOC/j8AQG1PmlLPmPi+p1hZny HPnI7TfF36R8OsElyVGVKuWzGdYJAPp2mX9tzUQ2YQ8xNMOAwlbTcsjjmldVSP8YkVEv 8M2xATZm11iIb++cUYMmzX3L3cwaHhGmUOEyFWH4F7mrP3/pHuvhLwITYw20ijtGEuoN jKo0bxn9wIzjEQSgK63JsjiBwoWJqAHTqpL8nOQnaiqrkjcX4kh2YCtKhTQ15tu1Ol5F YtUpFxBNMDe3pv7EEN/fzBP3L5ki3cERsj8/EJ/uw6wEAoJUr49XllCAIUhIc4yEzFsS uJ4w== X-Gm-Message-State: AA+aEWblbKQqhe3jVZM6CLMnOnxrq9+2mZ+beG8K293K6k4tVRmPisFk cssMgjvCaCsO45T9LSPRkvyaLA== X-Google-Smtp-Source: AFSGD/VxET1oVt24BqIeyvVIB9B9KDrV/eZ1ANkti5jRWK7TaQob+R5u44BJACGZzOlho23GjXhRNg== X-Received: by 2002:a63:bd1a:: with SMTP id a26mr12159678pgf.121.1544478282281; Mon, 10 Dec 2018 13:44:42 -0800 (PST) Received: from [192.168.1.121] (66.29.188.166.static.utbb.net. [66.29.188.166]) by smtp.gmail.com with ESMTPSA id 64sm16187094pff.101.2018.12.10.13.44.40 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 10 Dec 2018 13:44:41 -0800 (PST) Subject: Re: [PATCH] mtip32xx: avoid using semaphores To: Arnd Bergmann Cc: Johannes Thumshirn , Hannes Reinecke , Bart Van Assche , Matthew Wilcox , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <20181210213459.1147671-1-arnd@arndb.de> From: Jens Axboe Message-ID: <6caf6fa4-15e5-a7ec-cec4-69e5ad70c090@kernel.dk> Date: Mon, 10 Dec 2018 14:44:39 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20181210213459.1147671-1-arnd@arndb.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 12/10/18 2:34 PM, Arnd Bergmann wrote: > The "cmd_slot_unal" semaphore is never used in a blocking way > but only as an atomic counter. Change the code to using > atomic_dec_if_positive() as a better API. Looks good to me. We should also convert the return to blk-mq when we hit failure here to BLK_STS_DEV_RESOURCE, but that's a separate patch. -- Jens Axboe