From patchwork Fri Feb 2 10:28:46 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Xu X-Patchwork-Id: 1894487 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=H0EyJ/1L; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4TRBtR0d9jz23g7 for ; Fri, 2 Feb 2024 21:32:47 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rVqoa-0000Cb-4q; Fri, 02 Feb 2024 05:30:32 -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 1rVqoV-0008Rc-BR for qemu-devel@nongnu.org; Fri, 02 Feb 2024 05:30:28 -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 1rVqoT-0001vG-R9 for qemu-devel@nongnu.org; Fri, 02 Feb 2024 05:30:27 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1706869824; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gQpm8kWXL8qqmYDuhCIkxNF1j+AUaRZ6kwdr9T8tKKM=; b=H0EyJ/1LWCfVUQJq0JF12PeI1xiU44UT2iL4J0tXHTVDlFpufjIiuzfy5A9bc1Ry/NS50B xDw+lkak4WQ5PYppYl94uIHS8/CBGGDT2O6I1C8B01piXLZWN8o0+f87gbZv1rJt0uL6Lg GWR+66vmG0FTOgkdp5C9Et4y9DKQQVc= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-655-vvlK9RwjOOCMi0KHr1PBxQ-1; Fri, 02 Feb 2024 05:30:20 -0500 X-MC-Unique: vvlK9RwjOOCMi0KHr1PBxQ-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id 2B3BF3C0009A; Fri, 2 Feb 2024 10:30:20 +0000 (UTC) Received: from x1n.redhat.com (unknown [10.72.116.87]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4241D40C9444; Fri, 2 Feb 2024 10:30:15 +0000 (UTC) From: peterx@redhat.com To: qemu-devel@nongnu.org Cc: Hao Xiang , Bryan Zhang , Fabiano Rosas , peterx@redhat.com, Avihai Horon , Yuan Liu , Prasad Pandit Subject: [PATCH v2 12/23] migration/multifd: multifd_send_prepare_header() Date: Fri, 2 Feb 2024 18:28:46 +0800 Message-ID: <20240202102857.110210-13-peterx@redhat.com> In-Reply-To: <20240202102857.110210-1-peterx@redhat.com> References: <20240202102857.110210-1-peterx@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.2 Received-SPF: pass client-ip=170.10.129.124; envelope-from=peterx@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -33 X-Spam_score: -3.4 X-Spam_bar: --- X-Spam_report: (-3.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.292, 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_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Peter Xu Introduce a helper multifd_send_prepare_header() to setup the header packet for multifd sender. It's fine to setup the IOV[0] _before_ send_prepare() because the packet buffer is already ready, even if the content is to be filled in. With this helper, we can already slightly clean up the zero copy path. Note that I explicitly put it into multifd.h, because I want it inlined directly into multifd*.c where necessary later. Reviewed-by: Fabiano Rosas Signed-off-by: Peter Xu --- migration/multifd.h | 8 ++++++++ migration/multifd.c | 16 ++++++++-------- 2 files changed, 16 insertions(+), 8 deletions(-) diff --git a/migration/multifd.h b/migration/multifd.h index 2e4ad0dc56..4ec005f53f 100644 --- a/migration/multifd.h +++ b/migration/multifd.h @@ -209,5 +209,13 @@ typedef struct { void multifd_register_ops(int method, MultiFDMethods *ops); +static inline void multifd_send_prepare_header(MultiFDSendParams *p) +{ + p->iov[0].iov_len = p->packet_len; + p->iov[0].iov_base = p->packet; + p->iovs_num++; +} + + #endif diff --git a/migration/multifd.c b/migration/multifd.c index 44163e4e28..cd4467aff4 100644 --- a/migration/multifd.c +++ b/migration/multifd.c @@ -712,10 +712,14 @@ static void *multifd_send_thread(void *opaque) if (qatomic_read(&p->pending_job)) { MultiFDPages_t *pages = p->pages; - if (use_zero_copy_send) { - p->iovs_num = 0; - } else { - p->iovs_num = 1; + p->iovs_num = 0; + + if (!use_zero_copy_send) { + /* + * Only !zerocopy needs the header in IOV; zerocopy will + * send it separately. + */ + multifd_send_prepare_header(p); } assert(pages->num); @@ -735,10 +739,6 @@ static void *multifd_send_thread(void *opaque) if (ret != 0) { break; } - } else { - /* Send header using the same writev call */ - p->iov[0].iov_len = p->packet_len; - p->iov[0].iov_base = p->packet; } ret = qio_channel_writev_full_all(p->c, p->iov, p->iovs_num, NULL,