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=-1.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_MED 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 D1719C46470 for ; Wed, 8 Aug 2018 14:40:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 86228214FE for ; Wed, 8 Aug 2018 14:40:32 +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="raDXFEyI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 86228214FE 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-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727420AbeHHRA1 (ORCPT ); Wed, 8 Aug 2018 13:00:27 -0400 Received: from mail-io0-f178.google.com ([209.85.223.178]:35489 "EHLO mail-io0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726931AbeHHRA1 (ORCPT ); Wed, 8 Aug 2018 13:00:27 -0400 Received: by mail-io0-f178.google.com with SMTP id w11-v6so2018521iob.2 for ; Wed, 08 Aug 2018 07:40:30 -0700 (PDT) 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=Fky1w3IiLYWpjQc1HI/NzZekrIbcoI7vSsjc4d14/Q0=; b=raDXFEyI5A3ZTJpl3XbEOizYOfXif0jE3tgpanG3s2WyTW1oQ/4CZbtBLuksASPd/2 mu8W4/ld/tS0FlRJN3L3DzdOxoDMyTz3jPWnF5elV4Huu5r4qf0E+OURn2A1EMiBHhP6 cHlLM/Jf5idwQAN1B9GYSl+JBb0neKBKvcMs5ppsFOWAVSMu6ccSG85jVA+x1LpJO5mI PtXWFhSR9IFviqTldNZsx2Nw4gJv+7kHe2q0N/krfAk8//hoDs3huO05TAuk53i+Fj3Y nL6v/Ve8E8r0kxZfilkxtIlMOZxt//azk8y2ku748RuA9ifIy4O0HdI+XPQnXopU+oXY +hlg== 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=Fky1w3IiLYWpjQc1HI/NzZekrIbcoI7vSsjc4d14/Q0=; b=EDGiTWG3DuNAZYgJohcBXDdIv8WulXYC7elXsSXHXOFjvm6OsLPK/FMi8KejN3iqFq 7MlWMU/IHVzSVNBCR3678rsvD67bqp0bdfR87eaqauN6mtel6iZPyQvxriz5IT0aEMPQ q3qfJ7GgghvP0Ht8Htq9aXamys6VhPK2Q6p2zyYfHRUffURUCKqgn6cQ3vGVEjPLu0nC V6C8l3ud9NQkvroodyTnXV0O/xEfvSJjPz8fB0/b/3g1a+NAjymnCFh0XR3WJkSRWDcE /Rpbrp8Zr71lddrJziiyxqOphzgCoHiI4asPZCRLf7G633B90NTkuwEGntYJBqFbxOaO TfwA== X-Gm-Message-State: AOUpUlHHimLscZEaFK8i5HwoZ1wBTTfBexjY02+KBfA3NZMyMdg38VtO 6E5iLfdl1dNdINij5oJnyG8vMQxISEk= X-Google-Smtp-Source: AA+uWPz3FWetwSerV93OE1BPPF9AM/mPqLk5IscVSbxqaL+d7eeUpl4CWUTo162M3HV1ohTNs6J/LA== X-Received: by 2002:a5e:cb47:: with SMTP id h7-v6mr2618594iok.178.1533739229062; Wed, 08 Aug 2018 07:40:29 -0700 (PDT) Received: from [192.168.1.212] (107.191.0.158.static.utbb.net. [107.191.0.158]) by smtp.gmail.com with ESMTPSA id b195-v6sm2768675itc.42.2018.08.08.07.40.27 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 08 Aug 2018 07:40:27 -0700 (PDT) Subject: Re: [PATCH V2] blk-mq: count the hctx as active before allocate tag To: Jianchao Wang Cc: tom.leiming@gmail.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <1533722212-20327-1-git-send-email-jianchao.w.wang@oracle.com> From: Jens Axboe Message-ID: Date: Wed, 8 Aug 2018 08:40:26 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.0 MIME-Version: 1.0 In-Reply-To: <1533722212-20327-1-git-send-email-jianchao.w.wang@oracle.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/8/18 3:56 AM, Jianchao Wang wrote: > Currently, we count the hctx as active after allocate driver tag > successfully. The other shared-tags users could exhaust the driver > tags and starve a non-active and waiting-tag hctx. Count the hctx as > active before try to allocate driver tag to fix this. Patch looks good, but please add some comments along the way. -- Jens Axboe