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 lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4257DF589CF for ; Thu, 23 Apr 2026 13:11:10 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wFtor-0007sm-Kk; Thu, 23 Apr 2026 09:10:15 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wFtok-0007lZ-NV for qemu-devel@nongnu.org; Thu, 23 Apr 2026 09:10:07 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wFtoh-0000sx-U3 for qemu-devel@nongnu.org; Thu, 23 Apr 2026 09:10:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1776949801; 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: in-reply-to:in-reply-to:references:references; bh=Yrt2d1UQo/uEdzcrW8OrSRjEvCxJaOzjH26WIm+POgg=; b=gTPX0VfYwaEDWJDHQ6mWwSofVL72s82NNIcpBhbgwVsNeOsZSoABSwZv2C/d9R0YrfZj5S efXRFjd0hqmKZzZv0OOgOb5B+ENPeah5z4ZWwUg94FMAWNW+/9gpg465mggaYStKl8G0Hi iOJt40nyIlvLI8+SjV7/PBFeqauUT7Q= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-287-1J4vL3i2PR-OU2ExcLP58g-1; Thu, 23 Apr 2026 09:09:57 -0400 X-MC-Unique: 1J4vL3i2PR-OU2ExcLP58g-1 X-Mimecast-MFC-AGG-ID: 1J4vL3i2PR-OU2ExcLP58g_1776949796 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 18CAD19560AA; Thu, 23 Apr 2026 13:09:56 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.44.22.30]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 85008180045E; Thu, 23 Apr 2026 13:09:55 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 34D0D21E6A28; Thu, 23 Apr 2026 15:09:53 +0200 (CEST) From: Markus Armbruster To: Zhang Chen Cc: qemu-devel , "Dr . David Alan Gilbert" , Eric Blake , "Michael S . Tsirkin" , Stefan Hajnoczi Subject: Re: [PATCH V6 13/14] qapi: examine IOThread attachment status via query-iothreads In-Reply-To: <20260410150457.85190-14-zhangckid@gmail.com> (Zhang Chen's message of "Fri, 10 Apr 2026 23:04:56 +0800") References: <20260410150457.85190-1-zhangckid@gmail.com> <20260410150457.85190-14-zhangckid@gmail.com> Date: Thu, 23 Apr 2026 15:09:53 +0200 Message-ID: <87340lomam.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 12 X-Spam_score: 1.2 X-Spam_bar: + X-Spam_report: (1.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Zhang Chen writes: > Extend the 'IOThreadInfo' structure to include attachment metrics. > This allows users to monitor the associated devices by identify them > by their QOM paths. > > New fields added to IOThreadInfo: > - @holders: IoThreadHolder(QOM path or block node name) of the devices > currently associated with this iothread. See "I'm confused" below. > > These fields are also exposed via the Human Monitor Interface (HMP) > command 'info iothreads' to assist with manual debugging and > performance tuning. > > Signed-off-by: Zhang Chen [...] > diff --git a/qapi/misc.json b/qapi/misc.json > index d65d8012b2..e173d54a5e 100644 > --- a/qapi/misc.json > +++ b/qapi/misc.json > @@ -94,7 +94,8 @@ > # @IoThreadHolderKind: > # > # @block-node: Block node name. > -# @qom-object: Standard QOM path. > +# > +# @qom-object: QOM path. > # > # Since: 11.0 > ## Squash this into PATCH 02, please. > @@ -104,7 +105,7 @@ > ## > # @IoThreadHolder: > # > -# @type: Current IoThread holder type support QOM path and Block node. > +# @type: Current IoThread holder type support QOM path and block node. This, too. > # > # Since: 11.0 > ## > @@ -124,6 +125,13 @@ > # > # @thread-id: ID of the underlying host thread > # > +# @holders: IoThreadHolder(QOM path or block node name) of the devices Space before ( > +# currently associated with this iothread. Users can pre-allocate I'm confused. What is holding what? A QOM object / block node / monitor holding an I/O thread? > +# multiple iothread objects to serve as a persistent thread pool. > +# When a device is hot-unplugged, it is detached from its > +# iothread, but the iothread remains available, allowing future > +# hot-plugged devices to attach to it. > +# > # @poll-max-ns: maximum polling time in ns, 0 means polling is > # disabled (since 2.9) > # > @@ -141,6 +149,7 @@ > { 'struct': 'IOThreadInfo', > 'data': {'id': 'str', > 'thread-id': 'int', > + 'holders': ['IoThreadHolder'], > 'poll-max-ns': 'int', > 'poll-grow': 'int', > 'poll-shrink': 'int', > @@ -166,6 +175,8 @@ > # { > # "id":"iothread0", > # "thread-id":3134, > +# "holders":["/machine/peripheral/blk1/virtio-backend", > +# "/machine/peripheral/blk0/virtio-backend"], > # "poll-max-ns":32768, > # "poll-grow":0, > # "poll-shrink":0, > @@ -174,6 +185,7 @@ > # { > # "id":"iothread1", > # "thread-id":3135, > +# "holders":["/machine/peripheral/blk2/virtio-backend"], > # "poll-max-ns":32768, > # "poll-grow":0, > # "poll-shrink":0,