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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id B53EEFCD0B4 for ; Wed, 18 Mar 2026 06:10:20 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1w2k66-00085E-R0; Wed, 18 Mar 2026 02:09:38 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1w2k65-00084i-0V for qemu-devel@nongnu.org; Wed, 18 Mar 2026 02:09:37 -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 1w2k63-0005eU-0U for qemu-devel@nongnu.org; Wed, 18 Mar 2026 02:09:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1773814173; 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=B7d/4IIKOs5x4vpYZz2T+iMjWHF8DJu3oifTs2yhIaU=; b=ZEQNpa2Q/gquA4/35/EtnHnwz6YhY/usztH1JqCUCzvFz+7bSw7HlTXck3O41GhsxZsVHF lQlp1ZmiuNHVYyIfRG7BS5kS3oQmdgtTg9XPvLWbzcScFpr+8V6MSSiL4Aztiql/4wFMVB NIT0d/EYlS28okPT5fNL/44OjO50Roo= 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-271-1-K00ulWNz6Q35p80ou8ew-1; Wed, 18 Mar 2026 02:09:29 -0400 X-MC-Unique: 1-K00ulWNz6Q35p80ou8ew-1 X-Mimecast-MFC-AGG-ID: 1-K00ulWNz6Q35p80ou8ew_1773814168 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (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 79F461956048; Wed, 18 Mar 2026 06:09:28 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.45.242.6]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id E8DC019560AB; Wed, 18 Mar 2026 06:09:27 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 9F21921E6937; Wed, 18 Mar 2026 07:09:25 +0100 (CET) From: Markus Armbruster To: Zhang Chen Cc: qemu-devel , "Dr . David Alan Gilbert" , Eric Blake , "Michael S . Tsirkin" , Stefan Hajnoczi Subject: Re: [PATCH V5 13/13] qapi: examine IOThread attachment status via query-iothreads In-Reply-To: <20260305142459.52559-14-zhangckid@gmail.com> (Zhang Chen's message of "Thu, 5 Mar 2026 22:24:59 +0800") References: <20260305142459.52559-1-zhangckid@gmail.com> <20260305142459.52559-14-zhangckid@gmail.com> Date: Wed, 18 Mar 2026 07:09:25 +0100 Message-ID: <87o6klfz3e.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 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: -3 X-Spam_score: -0.4 X-Spam_bar: / X-Spam_report: (-0.4 / 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_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.819, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.903, 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: A string containing of QOM paths for the attached devices. > > 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 1f5062df2a..a381074c04 100644 > --- a/qapi/misc.json > +++ b/qapi/misc.json > @@ -76,6 +76,15 @@ > # > # @thread-id: ID of the underlying host thread > # > +# @holders: The parameter is an array of QOM paths indicating how many > +# active devices are currently associated with this iothread > +# (e.g. virtio-blk). In hotplug scenarios, users can > +# pre-allocate multiple iothread objects to serve as a persistent > +# thread pool. When a device is hot-unplugged, the corresponding > +# IOThread is released but remains available, allowing subsequent > +# hot-plugged devices to attach to and reuse the existing thread. > +# Returns empty if no devices are attached. (since 11.0) Let me try to polish this a bit: # @holders: QOM paths of the devices currently associated with this # iothread. Users can pre-allocate 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) > # > @@ -93,6 +102,7 @@ > { 'struct': 'IOThreadInfo', > 'data': {'id': 'str', > 'thread-id': 'int', > + 'holders': ['str'], > 'poll-max-ns': 'int', > 'poll-grow': 'int', > 'poll-shrink': 'int', > @@ -118,6 +128,8 @@ > # { > # "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, > @@ -126,6 +138,7 @@ > # { > # "id":"iothread1", > # "thread-id":3135, > +# "holders":["/machine/peripheral/blk2/virtio-backend"], > # "poll-max-ns":32768, > # "poll-grow":0, > # "poll-shrink":0, With a bit of doc polish: Acked-by: Markus Armbruster