From patchwork Mon May 25 09:38:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 11568467 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4418F1391 for ; Mon, 25 May 2020 09:38:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2C52A207FB for ; Mon, 25 May 2020 09:38:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ch/eTvUp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389366AbgEYJiW (ORCPT ); Mon, 25 May 2020 05:38:22 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:26747 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2389365AbgEYJiW (ORCPT ); Mon, 25 May 2020 05:38:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1590399500; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=WyzP7ZR80ZE9A05rUQ0VvkTLGhBpXq3iTKDC7gF6Yjg=; b=ch/eTvUpV5GuwSktrr/H1RzmNB3XVmlroEWWX+MYVYzj9l9D7JnI7NmzI2TZpxHdhTTS9U kSMblFV1GF5svHgPcroC8ni7N+1PX4xHSLZbFZ/p2As07kY+N/DHZje/l9cTfNOZjmvZ18 lJIcZ4c9VxeTxgHsuuwCkHoA0rEZbuM= 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-131-wFW1hXxiN4mYitKsgFnJOw-1; Mon, 25 May 2020 05:38:16 -0400 X-MC-Unique: wFW1hXxiN4mYitKsgFnJOw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 75B7D460; Mon, 25 May 2020 09:38:15 +0000 (UTC) Received: from localhost (ovpn-12-137.pek2.redhat.com [10.72.12.137]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0862B5D9C5; Mon, 25 May 2020 09:38:11 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Ming Lei , Sagi Grimberg , Baolin Wang , Christoph Hellwig Subject: [PATCH V2 0/6] blk-mq: support batching dispatch from scheduler Date: Mon, 25 May 2020 17:38:01 +0800 Message-Id: <20200525093807.805155-1-ming.lei@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi Guys, More and more drivers want to get batching requests queued from block layer, such as mmc[1], and tcp based storage drivers[2]. Also current in-tree users have virtio-scsi, virtio-blk and nvme. For none, we already support batching dispatch. But for io scheduler, every time we just take one request from scheduler and pass the single request to blk_mq_dispatch_rq_list(). This way makes batching dispatch not possible when io scheduler is applied. One reason is that we don't want to hurt sequential IO performance, becasue IO merge chance is reduced if more requests are dequeued from scheduler queue. Tries to start the support by dequeuing more requests from scheduler if budget is enough and device isn't busy. Simple fio test over virtio-scsi shows IO can get improved by 5~10%. Baolin has tested V1 and found performance on MMC can be improved. Patches can be found from the following tree too: https://github.com/ming1/linux/commits/v5.7-rc-blk-mq-batching-submission Patch 1 ~ 4 are improvement and cleanup, which can't applied without supporting batching dispatch. Patch 5 ~ 6 starts to support batching dispatch from scheduler. [1] https://lore.kernel.org/linux-block/20200512075501.GF1531898@T590/#r [2] https://lore.kernel.org/linux-block/fe6bd8b9-6ed9-b225-f80c-314746133722@grimberg.me/ V2: - remove 'got_budget' from blk_mq_dispatch_rq_list - drop patch for getting driver tag & handling partial dispatch Ming Lei (6): blk-mq: pass request queue into get/put budget callback blk-mq: pass hctx to blk_mq_dispatch_rq_list blk-mq: move getting driver tag and bugget into one helper blk-mq: remove dead check from blk_mq_dispatch_rq_list blk-mq: pass obtained budget count to blk_mq_dispatch_rq_list blk-mq: support batching dispatch in case of io scheduler block/blk-mq-sched.c | 95 ++++++++++++++++++++++++++++++++----- block/blk-mq.c | 101 ++++++++++++++++++++++++---------------- block/blk-mq.h | 15 +++--- drivers/scsi/scsi_lib.c | 8 ++-- include/linux/blk-mq.h | 4 +- 5 files changed, 154 insertions(+), 69 deletions(-) Cc: Sagi Grimberg Cc: Baolin Wang Cc: Christoph Hellwig