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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 98199C433EF for ; Tue, 2 Nov 2021 16:19:41 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3EEA461058 for ; Tue, 2 Nov 2021 16:19:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 3EEA461058 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:33822 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mhwVg-0007Hr-6S for qemu-devel@archiver.kernel.org; Tue, 02 Nov 2021 12:19:40 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53210) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mhwIT-0007Tt-FD for qemu-devel@nongnu.org; Tue, 02 Nov 2021 12:06:01 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:53579) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mhwIP-0004H0-Nm for qemu-devel@nongnu.org; Tue, 02 Nov 2021 12:06:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1635869157; 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=2yaeXp60C3PL+8woDk8pCgZK+CYPg2Ar/I5u3jiWTqw=; b=VAapjMgeIc02EgSOGBdA6aswUepZfA3wTch5c+cYWNyOUn0LOtTfKEcqTPZ9TWHXp/RmEU DTj6pjHNMl+YRj+0JOuBjhLUPnqUPuq+kmpWytQZV1zEm307J4m8JfGuxn63VQgZDmZ3TU 6sK7fyAbCr+pVZS+brrHSpXyGES4VAw= 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-113-jHDSdvgKOJ-wTgbTS7TKkg-1; Tue, 02 Nov 2021 12:05:54 -0400 X-MC-Unique: jHDSdvgKOJ-wTgbTS7TKkg-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 DFF0E1006AA7; Tue, 2 Nov 2021 16:05:52 +0000 (UTC) Received: from merkur.redhat.com (unknown [10.39.193.81]) by smtp.corp.redhat.com (Postfix) with ESMTP id E92CD5D9D3; Tue, 2 Nov 2021 16:05:51 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Subject: [PULL 06/12] file-posix: add `aio-max-batch` option Date: Tue, 2 Nov 2021 17:05:22 +0100 Message-Id: <20211102160528.206766-7-kwolf@redhat.com> In-Reply-To: <20211102160528.206766-1-kwolf@redhat.com> References: <20211102160528.206766-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kwolf@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=170.10.129.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.702, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, peter.maydell@linaro.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Stefano Garzarella Commit d7ddd0a161 ("linux-aio: limit the batch size using `aio-max-batch` parameter") added a way to limit the batch size of Linux AIO backend for the entire AIO context. The same AIO context can be shared by multiple devices, so latency-sensitive devices may want to limit the batch size even more to avoid increasing latency. For this reason we add the `aio-max-batch` option to the file backend, which will be used by the next commits to limit the size of batches including requests generated by this device. Suggested-by: Kevin Wolf Reviewed-by: Kevin Wolf Signed-off-by: Stefano Garzarella Message-Id: <20211026162346.253081-2-sgarzare@redhat.com> Reviewed-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- qapi/block-core.json | 7 +++++++ block/file-posix.c | 9 +++++++++ 2 files changed, 16 insertions(+) diff --git a/qapi/block-core.json b/qapi/block-core.json index ce2c1352cb..ea36e0038c 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -2939,6 +2939,12 @@ # for this device (default: none, forward the commands via SG_IO; # since 2.11) # @aio: AIO backend (default: threads) (since: 2.8) +# @aio-max-batch: maximum number of requests to batch together into a single +# submission in the AIO backend. The smallest value between +# this and the aio-max-batch value of the IOThread object is +# chosen. +# 0 means that the AIO backend will handle it automatically. +# (default: 0, since 6.2) # @locking: whether to enable file locking. If set to 'auto', only enable # when Open File Descriptor (OFD) locking API is available # (default: auto, since 2.10) @@ -2968,6 +2974,7 @@ '*pr-manager': 'str', '*locking': 'OnOffAuto', '*aio': 'BlockdevAioOptions', + '*aio-max-batch': 'int', '*drop-cache': {'type': 'bool', 'if': 'CONFIG_LINUX'}, '*x-check-cache-dropped': { 'type': 'bool', diff --git a/block/file-posix.c b/block/file-posix.c index 6def2a4cba..7a289a9481 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -150,6 +150,8 @@ typedef struct BDRVRawState { uint64_t locked_perm; uint64_t locked_shared_perm; + uint64_t aio_max_batch; + int perm_change_fd; int perm_change_flags; BDRVReopenState *reopen_state; @@ -530,6 +532,11 @@ static QemuOptsList raw_runtime_opts = { .type = QEMU_OPT_STRING, .help = "host AIO implementation (threads, native, io_uring)", }, + { + .name = "aio-max-batch", + .type = QEMU_OPT_NUMBER, + .help = "AIO max batch size (0 = auto handled by AIO backend, default: 0)", + }, { .name = "locking", .type = QEMU_OPT_STRING, @@ -609,6 +616,8 @@ static int raw_open_common(BlockDriverState *bs, QDict *options, s->use_linux_io_uring = (aio == BLOCKDEV_AIO_OPTIONS_IO_URING); #endif + s->aio_max_batch = qemu_opt_get_number(opts, "aio-max-batch", 0); + locking = qapi_enum_parse(&OnOffAuto_lookup, qemu_opt_get(opts, "locking"), ON_OFF_AUTO_AUTO, &local_err); -- 2.31.1