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=-5.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 1C9F6CA9EAF for ; Thu, 24 Oct 2019 14:59:45 +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 DC09620650 for ; Thu, 24 Oct 2019 14:59:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="PNC271jp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DC09620650 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:44868 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNeaU-0006BW-7o for qemu-devel@archiver.kernel.org; Thu, 24 Oct 2019 10:59:44 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33396) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNdbp-0001JN-77 for qemu-devel@nongnu.org; Thu, 24 Oct 2019 09:57:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iNdbn-0003jW-2v for qemu-devel@nongnu.org; Thu, 24 Oct 2019 09:57:00 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:40812 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iNdbm-0003j5-UO for qemu-devel@nongnu.org; Thu, 24 Oct 2019 09:56:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1571925418; 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=LLh4sH6giV5qwkksrveGe51we5sb34+CNwTVgdLK1yo=; b=PNC271jp8z9T0HwVvn2wj8BqYfw7rmDPKIjb3sTVPgsHBS7d5ugGZIMZUlCytOrX7YHjUw HMCLsJ6my4A6v0oysS2iEu5GQq9WB1IkUtDe/ZSTROW/60mM3uMy8c8MUDy1+tY/RPOFVG vlLE+Z1qJwku7Qf2vvWGPMZSI1uGipQ= 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-156-gzni6ymLMwuBaL9szP4sCw-1; Thu, 24 Oct 2019 09:56:54 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0D8021005500; Thu, 24 Oct 2019 13:56:52 +0000 (UTC) Received: from work-vm (ovpn-117-248.ams2.redhat.com [10.36.117.248]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 1AC86600CC; Thu, 24 Oct 2019 13:56:47 +0000 (UTC) Date: Thu, 24 Oct 2019 14:56:45 +0100 From: "Dr. David Alan Gilbert" To: Zhenyu Ye Subject: Re: [RFC PATCH] iothread: add set_iothread_poll_* commands Message-ID: <20191024135645.GG2877@work-vm> References: <5DAEB9D3.3080503@huawei.com> <20191023151903.GI9574@stefanha-x1.localdomain> <5DB1ACF2.9080500@huawei.com> MIME-Version: 1.0 In-Reply-To: <5DB1ACF2.9080500@huawei.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: gzni6ymLMwuBaL9szP4sCw-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-devel@nongnu.org, xiexiangyou@huawei.com, jiangyiwen , Stefan Hajnoczi , pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Zhenyu Ye (yezhenyu2@huawei.com) wrote: >=20 >=20 > On 2019/10/23 23:19, Stefan Hajnoczi wrote: > > On Tue, Oct 22, 2019 at 04:12:03PM +0800, yezhenyu (A) wrote: > >> Since qemu2.9, QEMU added three AioContext poll parameters to struct > >> IOThread: poll_max_ns, poll_grow and poll_shrink. These properties are > >> used to control iothread polling time. > >> > >> However, there isn't properly hmp commands to adjust them when the VM = is > >> alive. It's useful to adjust them online when observing the impact of > >> different property value on performance. > >> > >> This patch add three hmp commands to adjust iothread poll-* properties > >> for special iothread: > >> > >> set_iothread_poll_max_ns: set the maximum polling time in ns; > >> set_iothread_poll_grow: set how many ns will be added to polling time; > >> set_iothread_poll_shrink: set how many ns will be removed from polling > >> time. > >> > >> Signed-off-by: Zhenyu Ye > >> --- > >> hmp-commands.hx | 42 ++++++++++++++++++++ > >> hmp.c | 30 +++++++++++++++ > >> hmp.h | 3 ++ > >> include/sysemu/iothread.h | 6 +++ > >> iothread.c | 80 +++++++++++++++++++++++++++++++++++++++ > >> qapi/misc.json | 23 +++++++++++ > >> 6 files changed, 184 insertions(+) > >=20 > > poll-max-ns, poll-grow, poll-shrink are properties of IOThread objects. > > They can already be modified at runtime using: > >=20 > > $ qemu -object iothread,id=3Diothread1 > > (qemu) qom-set /objects/iothread1 poll-max-ns 100000 > >=20 > > I think there is no need for a patch. > >=20 > > Stefan > >=20 >=20 > Thanks for your review. I have considered using the `qom-set` command to = modify > IOThread object's properties, however, this command is not friendly to pr= imary > users. The help info for this command is only: >=20 > qom-set path property value -- set QOM property >=20 > It's almost impossible to get the correct `path` parameter for primary us= er. Is this just a matter of documenting how to do it? It sounds like there's no need for a new QMP command though; if you want an easier HMP command I'd probably still take it (because HMP is ok at having things for convenience) - but not if it turns out that just adding a paragraph of documentation is enough. Dave > This patch provides a more convenient and easy-use hmp&qmp interface to m= odify > these IOThread properties. I think this patch still has a little value. >=20 > And I can implement this patch compactly by reusing your code. >=20 > Waiting for your reply. >=20 -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK