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 9FA65CCFA04 for ; Tue, 4 Nov 2025 11:14:50 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vGEzI-00022W-4m; Tue, 04 Nov 2025 06:14:08 -0500 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 1vGEzD-00021a-NO for qemu-devel@nongnu.org; Tue, 04 Nov 2025 06:14:04 -0500 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 1vGEzC-0008Nj-Dm for qemu-devel@nongnu.org; Tue, 04 Nov 2025 06:14:03 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1762254841; 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=W9QV/8EEPBIg/49QVHWGfkIBpSQSAvXNW36V51zOGrI=; b=fzQ1x4Hxbam0EOFAZA6zK8eqdrk64+nwkE9uZGLxi90K5z95QSs1hir0FALFfPUmIS98Cu 9Yz14+kQesyQHXeapsvZHJ6QQEAAnT6k2sIyN/iv/FmlMpZvOxg8Xm1bU6rUQ2o7zXt6jy ZqcgWhTGtlN26N0UuLbQ9VqrU1Qbt+Q= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-61-u-Vjw3WNNtabi57BXQETAw-1; Tue, 04 Nov 2025 06:13:58 -0500 X-MC-Unique: u-Vjw3WNNtabi57BXQETAw-1 X-Mimecast-MFC-AGG-ID: u-Vjw3WNNtabi57BXQETAw_1762254837 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-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1F8DB1808981; Tue, 4 Nov 2025 11:13:57 +0000 (UTC) Received: from redhat.com (unknown [10.45.226.47]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 76D8918004D4; Tue, 4 Nov 2025 11:13:55 +0000 (UTC) Date: Tue, 4 Nov 2025 12:13:52 +0100 From: Kevin Wolf To: Eric Blake Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, berrange@redhat.com Subject: Re: [PATCH 2/8] qio: Minor optimization when callback function is unchanged Message-ID: References: <20251103202849.3687643-10-eblake@redhat.com> <20251103202849.3687643-12-eblake@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251103202849.3687643-12-eblake@redhat.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 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: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 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_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=unavailable 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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Am 03.11.2025 um 21:10 hat Eric Blake geschrieben: > In qemu-nbd and other NBD server setups where parallel clients are > supported, it is common that the caller will re-register the same > callback function as long as it has not reached its limit on > simultaneous clients. In that case, there is no need to tear down and > reinstall GSource watches in the GMainContext. > > Signed-off-by: Eric Blake > --- > io/net-listener.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/io/net-listener.c b/io/net-listener.c > index 0adbc409cf2..e89286ea63c 100644 > --- a/io/net-listener.c > +++ b/io/net-listener.c > @@ -147,6 +147,10 @@ void qio_net_listener_set_client_func_full(QIONetListener *listener, > { > size_t i; > > + if (listener->io_func == func && listener->io_data == data) { > + return; > + } Wouldn't a change of listener->io_notify also be significant? Kevin