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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 BA017C433DF for ; Wed, 27 May 2020 22:52:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9A4812084C for ; Wed, 27 May 2020 22:52:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725385AbgE0Wws (ORCPT ); Wed, 27 May 2020 18:52:48 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:42885 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725267AbgE0Wws (ORCPT ); Wed, 27 May 2020 18:52:48 -0400 Received: by mail-pl1-f196.google.com with SMTP id x11so9742988plv.9 for ; Wed, 27 May 2020 15:52:48 -0700 (PDT) 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:autocrypt :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=/EgT6JLYV4/szy3xpKpygU2i1QsH8y8xW5bMYvlmouc=; b=Bk4vjxwph6UDg3+tQoNfKh4FXx3ZoMUBqEzDZ/K4P3qJ02i2wqaW4CL/WAs71JOon1 zjPvI4Fw4f7KSfiqtNdnuLW+rALER2gbt8yyR3trSw1f0Q5HKDNQLNrc45VS/vpzXnyE 3YUzRWRyZpBw8S0tuk7u98z1Wm/X7C2kp/uH41FLHYQyv5wsMdMJ/4pgdEjab4G68Wn9 NvU6EFutUEC/ucOzcb2mRyb2It06QA37YPtitGKIaY3IhNRIh+c9dWMux545tw+t5EAq mZfm+WlzcyizMDcfzewo5hvffQl2Aw0ztd8lOFUij7zUqCBWn6XEjfUlS7KRxR7eAPbE aM0g== X-Gm-Message-State: AOAM531oW9/HY5dE5tqdAYWru6W0YSy+QWVp9i2X09RdTVKzPQbLWjG2 7G0EWlk3YNRBHO5VgMmZctE= X-Google-Smtp-Source: ABdhPJzg3ltNUDaCNxvd63S0HGwdewVZFYic+rQMYRnMoJ9uxGHpNnDh6AEU2KWZzQqHsbBM7vFFUw== X-Received: by 2002:a17:902:9342:: with SMTP id g2mr639631plp.326.1590619967459; Wed, 27 May 2020 15:52:47 -0700 (PDT) Received: from [192.168.50.147] (c-73-241-217-19.hsd1.ca.comcast.net. [73.241.217.19]) by smtp.gmail.com with ESMTPSA id w190sm2845598pfw.35.2020.05.27.15.52.45 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 27 May 2020 15:52:46 -0700 (PDT) Subject: Re: [PATCH 7/8] blk-mq: add blk_mq_all_tag_iter To: Christoph Hellwig Cc: linux-block@vger.kernel.org, John Garry , Hannes Reinecke , Thomas Gleixner , Ming Lei References: <20200527180644.514302-1-hch@lst.de> <20200527180644.514302-8-hch@lst.de> From: Bart Van Assche Autocrypt: addr=bvanassche@acm.org; prefer-encrypt=mutual; keydata= mQENBFSOu4oBCADcRWxVUvkkvRmmwTwIjIJvZOu6wNm+dz5AF4z0FHW2KNZL3oheO3P8UZWr LQOrCfRcK8e/sIs2Y2D3Lg/SL7qqbMehGEYcJptu6mKkywBfoYbtBkVoJ/jQsi2H0vBiiCOy fmxMHIPcYxaJdXxrOG2UO4B60Y/BzE6OrPDT44w4cZA9DH5xialliWU447Bts8TJNa3lZKS1 AvW1ZklbvJfAJJAwzDih35LxU2fcWbmhPa7EO2DCv/LM1B10GBB/oQB5kvlq4aA2PSIWkqz4 3SI5kCPSsygD6wKnbRsvNn2mIACva6VHdm62A7xel5dJRfpQjXj2snd1F/YNoNc66UUTABEB AAG0JEJhcnQgVmFuIEFzc2NoZSA8YnZhbmFzc2NoZUBhY20ub3JnPokBOQQTAQIAIwUCVI67 igIbAwcLCQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJEHFcPTXFzhAJ8QkH/1AdXblKL65M Y1Zk1bYKnkAb4a98LxCPm/pJBilvci6boefwlBDZ2NZuuYWYgyrehMB5H+q+Kq4P0IBbTqTa jTPAANn62A6jwJ0FnCn6YaM9TZQjM1F7LoDX3v+oAkaoXuq0dQ4hnxQNu792bi6QyVdZUvKc macVFVgfK9n04mL7RzjO3f+X4midKt/s+G+IPr4DGlrq+WH27eDbpUR3aYRk8EgbgGKvQFdD CEBFJi+5ZKOArmJVBSk21RHDpqyz6Vit3rjep7c1SN8s7NhVi9cjkKmMDM7KYhXkWc10lKx2 RTkFI30rkDm4U+JpdAd2+tP3tjGf9AyGGinpzE2XY1K5AQ0EVI67igEIAKiSyd0nECrgz+H5 PcFDGYQpGDMTl8MOPCKw/F3diXPuj2eql4xSbAdbUCJzk2ETif5s3twT2ER8cUTEVOaCEUY3 eOiaFgQ+nGLx4BXqqGewikPJCe+UBjFnH1m2/IFn4T9jPZkV8xlkKmDUqMK5EV9n3eQLkn5g lco+FepTtmbkSCCjd91EfThVbNYpVQ5ZjdBCXN66CKyJDMJ85HVr5rmXG/nqriTh6cv1l1Js T7AFvvPjUPknS6d+BETMhTkbGzoyS+sywEsQAgA+BMCxBH4LvUmHYhpS+W6CiZ3ZMxjO8Hgc ++w1mLeRUvda3i4/U8wDT3SWuHcB3DWlcppECLkAEQEAAYkBHwQYAQIACQUCVI67igIbDAAK CRBxXD01xc4QCZ4dB/0QrnEasxjM0PGeXK5hcZMT9Eo998alUfn5XU0RQDYdwp6/kMEXMdmT oH0F0xB3SQ8WVSXA9rrc4EBvZruWQ+5/zjVrhhfUAx12CzL4oQ9Ro2k45daYaonKTANYG22y //x8dLe2Fv1By4SKGhmzwH87uXxbTJAUxiWIi1np0z3/RDnoVyfmfbbL1DY7zf2hYXLLzsJR mSsED/1nlJ9Oq5fALdNEPgDyPUerqHxcmIub+pF0AzJoYHK5punqpqfGmqPbjxrJLPJfHVKy goMj5DlBMoYqEgpbwdUYkH6QdizJJCur4icy8GUNbisFYABeoJ91pnD4IGei3MTdvINSZI5e Message-ID: <413f73b7-436b-9319-b589-e6fef370fb39@acm.org> Date: Wed, 27 May 2020 15:52:44 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200527180644.514302-8-hch@lst.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 2020-05-27 11:06, Christoph Hellwig wrote: > @@ -308,21 +312,28 @@ static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt, > } > > /** > - * blk_mq_all_tag_busy_iter - iterate over all started requests in a tag map > + * blk_mq_all_tag_iter - iterate over all requests in a tag map > * @tags: Tag map to iterate over. > - * @fn: Pointer to the function that will be called for each started > + * @fn: Pointer to the function that will be called for each > * request. @fn will be called as follows: @fn(rq, @priv, > * reserved) where rq is a pointer to a request. 'reserved' > * indicates whether or not @rq is a reserved request. Return > * true to continue iterating tags, false to stop. > * @priv: Will be passed as second argument to @fn. > */ Please document the new 'flags' argument in the kernel-doc header. > -static void blk_mq_all_tag_busy_iter(struct blk_mq_tags *tags, > - busy_tag_iter_fn *fn, void *priv) > +static void __blk_mq_all_tag_iter(struct blk_mq_tags *tags, > + busy_tag_iter_fn *fn, void *priv, unsigned int flags) > { > if (tags->nr_reserved_tags) > - bt_tags_for_each(tags, &tags->breserved_tags, fn, priv, true); > - bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, false); > + bt_tags_for_each(tags, &tags->breserved_tags, fn, priv, > + flags | BT_TAG_ITER_RESERVED); > + bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, flags); > +} The meaning of the 'reserved' argument passed to bt_for_each() and also to busy_iter_fn is 'the request argument is a reserved request'. If BT_TAG_ITER_RESERVED would be set in the 'flags' argument then the wrong value will be passed for the 'reserved' argument in the second bt_tags_for_each() call. So I think we need something like the following at the start of __blk_mq_all_tag_iter(): WARN_ON_ONCE(flags & BT_TAG_ITER_RESERVED) Otherwise this patch looks good to me. Thanks, Bart.