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=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 4D506C433E0 for ; Mon, 18 Jan 2021 05:27:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0B1BB2231F for ; Mon, 18 Jan 2021 05:27:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728799AbhARF1Z (ORCPT ); Mon, 18 Jan 2021 00:27:25 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:39817 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726390AbhARF1Y (ORCPT ); Mon, 18 Jan 2021 00:27:24 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610947557; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=hpA/2lzEvO8o3CZnJ/P9NlQ95nOpAYmzv3dugnKebyQ=; b=cMZsimiEr4Nrtb4d/7yAokDVS3xy69BQEAkKMIWjU8PPQXflCukA7K686+bYfGRHWtceRs XgXMtAf52EqiRXxRgdxQ5Wjo5VHqrP/DfQX8tHoGxSk9g0pkNhiMCVfrYYS924eMwD6MkO hNrrIcBkPefQT2l3YcbL38KulE8hYhk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-589-ANpXt0OaPciHHPNmoIbdLw-1; Mon, 18 Jan 2021 00:25:53 -0500 X-MC-Unique: ANpXt0OaPciHHPNmoIbdLw-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C710A180A098; Mon, 18 Jan 2021 05:25:51 +0000 (UTC) Received: from [10.72.13.12] (ovpn-13-12.pek2.redhat.com [10.72.13.12]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1B84C5D72E; Mon, 18 Jan 2021 05:25:46 +0000 (UTC) Subject: Re: [PATCH RFC] virtio-blk: support per-device queue depth To: Joseph Qi , "Michael S. Tsirkin" Cc: virtualization@lists.linux-foundation.org, linux-block@vger.kernel.org, Jeffle Xu References: <1610942338-78252-1-git-send-email-joseph.qi@linux.alibaba.com> From: Jason Wang Message-ID: Date: Mon, 18 Jan 2021 13:25:45 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <1610942338-78252-1-git-send-email-joseph.qi@linux.alibaba.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 2021/1/18 上午11:58, Joseph Qi wrote: > module parameter 'virtblk_queue_depth' was firstly introduced for > testing/benchmarking purposes described in commit fc4324b4597c > ("virtio-blk: base queue-depth on virtqueue ringsize or module param"). > Since we have different virtio-blk devices which have different > capabilities, it requires that we support per-device queue depth instead > of per-module. So defaultly use vq free elements if module parameter > 'virtblk_queue_depth' is not set. I wonder if it's better to use sysfs instead (or whether it has already had something like this in the blocker layer). Thanks > > Signed-off-by: Joseph Qi > --- > drivers/block/virtio_blk.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c > index 145606d..f83a417 100644 > --- a/drivers/block/virtio_blk.c > +++ b/drivers/block/virtio_blk.c > @@ -705,6 +705,7 @@ static int virtblk_probe(struct virtio_device *vdev) > u32 v, blk_size, max_size, sg_elems, opt_io_size; > u16 min_io_size; > u8 physical_block_exp, alignment_offset; > + unsigned int queue_depth; > > if (!vdev->config->get) { > dev_err(&vdev->dev, "%s failure: config access disabled\n", > @@ -755,17 +756,18 @@ static int virtblk_probe(struct virtio_device *vdev) > goto out_free_vq; > } > > - /* Default queue sizing is to fill the ring. */ > - if (!virtblk_queue_depth) { > - virtblk_queue_depth = vblk->vqs[0].vq->num_free; > + if (likely(!virtblk_queue_depth)) { > + queue_depth = vblk->vqs[0].vq->num_free; > /* ... but without indirect descs, we use 2 descs per req */ > if (!virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC)) > - virtblk_queue_depth /= 2; > + queue_depth /= 2; > + } else { > + queue_depth = virtblk_queue_depth; > } > > memset(&vblk->tag_set, 0, sizeof(vblk->tag_set)); > vblk->tag_set.ops = &virtio_mq_ops; > - vblk->tag_set.queue_depth = virtblk_queue_depth; > + vblk->tag_set.queue_depth = queue_depth; > vblk->tag_set.numa_node = NUMA_NO_NODE; > vblk->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; > vblk->tag_set.cmd_size =