From nobody Tue Feb 10 01:30:38 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1646926880176929.6494456104296; Thu, 10 Mar 2022 07:41:20 -0800 (PST) Received: from localhost ([::1]:56636 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nSKuk-0006ok-Vh for importer@patchew.org; Thu, 10 Mar 2022 10:41:18 -0500 Received: from eggs.gnu.org ([209.51.188.92]:36148) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nSKox-0003em-HA for qemu-devel@nongnu.org; Thu, 10 Mar 2022 10:35:21 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:37884) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nSKow-0004Ik-0A for qemu-devel@nongnu.org; Thu, 10 Mar 2022 10:35:19 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-509-UBYx1s-oPmieMmpqzYijZg-1; Thu, 10 Mar 2022 10:35:16 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 07C0D800D55; Thu, 10 Mar 2022 15:35:15 +0000 (UTC) Received: from secure.mitica (unknown [10.39.192.52]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1B5507DE43; Thu, 10 Mar 2022 15:35:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646926517; 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=Hy/jvMR/NmIxqgxWeXXMojUMtHbV0sZkV4HPX2gHOmg=; b=DnkTlyoLiPziU+SuHozpLnHm6BlMhrTefcgcJcidQQxxw8kfHpTk4jZGeVS9JwmGodG4Vp rGXGJZhlpohqmTbWp76+wu9iTyVC4kcYEg4wn1L7FNd6zX+SFp7BN703tbKVZSbVD36Tbn ivYAJ532KAFxe/0jQrw1eVj7LlHiD8s= X-MC-Unique: UBYx1s-oPmieMmpqzYijZg-1 From: Juan Quintela To: qemu-devel@nongnu.org Subject: [PATCH v5 7/8] multifd: Zero pages transmission Date: Thu, 10 Mar 2022 16:34:53 +0100 Message-Id: <20220310153454.3929-8-quintela@redhat.com> In-Reply-To: <20220310153454.3929-1-quintela@redhat.com> References: <20220310153454.3929-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=quintela@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=quintela@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, 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_H5=0.001, RCVD_IN_MSPIKE_WL=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: , Cc: Eduardo Habkost , Juan Quintela , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Peter Xu , "Dr. David Alan Gilbert" , Yanan Wang , Leonardo Bras Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1646926881198100001 Content-Type: text/plain; charset="utf-8" This implements the zero page dection and handling. Signed-off-by: Juan Quintela --- Add comment for offset (dave) Use local variables for offset/block to have shorter lines --- migration/multifd.h | 5 +++++ migration/multifd.c | 42 ++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 45 insertions(+), 2 deletions(-) diff --git a/migration/multifd.h b/migration/multifd.h index 06c52081ab..e84ce0ebcd 100644 --- a/migration/multifd.h +++ b/migration/multifd.h @@ -54,6 +54,11 @@ typedef struct { uint32_t unused32[1]; /* Reserved for future use */ uint64_t unused64[3]; /* Reserved for future use */ char ramblock[256]; + /* + * This array contains the pointers to: + * - normal pages (initial normal_pages entries) + * - zero pages (following zero_pages entries) + */ uint64_t offset[]; } __attribute__((packed)) MultiFDPacket_t; =20 diff --git a/migration/multifd.c b/migration/multifd.c index 41769ff99f..1d7b6ffe24 100644 --- a/migration/multifd.c +++ b/migration/multifd.c @@ -11,6 +11,7 @@ */ =20 #include "qemu/osdep.h" +#include "qemu/cutils.h" #include "qemu/rcu.h" #include "exec/target_page.h" #include "sysemu/sysemu.h" @@ -277,6 +278,12 @@ static void multifd_send_fill_packet(MultiFDSendParams= *p) =20 packet->offset[i] =3D cpu_to_be64(temp); } + for (i =3D 0; i < p->zero_num; i++) { + /* there are architectures where ram_addr_t is 32 bit */ + uint64_t temp =3D p->zero[i]; + + packet->offset[p->normal_num + i] =3D cpu_to_be64(temp); + } } =20 static int multifd_recv_unfill_packet(MultiFDRecvParams *p, Error **errp) @@ -362,6 +369,18 @@ static int multifd_recv_unfill_packet(MultiFDRecvParam= s *p, Error **errp) p->normal[i] =3D offset; } =20 + for (i =3D 0; i < p->zero_num; i++) { + uint64_t offset =3D be64_to_cpu(packet->offset[p->normal_num + i]); + + if (offset > (block->used_length - page_size)) { + error_setg(errp, "multifd: offset too long %" PRIu64 + " (max " RAM_ADDR_FMT ")", + offset, block->used_length); + return -1; + } + p->zero[i] =3D offset; + } + return 0; } =20 @@ -624,6 +643,8 @@ static void *multifd_send_thread(void *opaque) { MultiFDSendParams *p =3D opaque; Error *local_err =3D NULL; + /* qemu older than 7.0 don't understand zero page on multifd channel */ + bool use_zero_page =3D migrate_use_multifd_zero_page(); int ret =3D 0; =20 trace_multifd_send_thread_start(p->id); @@ -645,6 +666,7 @@ static void *multifd_send_thread(void *opaque) qemu_mutex_lock(&p->mutex); =20 if (p->pending_job) { + RAMBlock *rb =3D p->pages->block; uint64_t packet_num =3D p->packet_num; uint32_t flags =3D p->flags; p->iovs_num =3D 1; @@ -652,8 +674,17 @@ static void *multifd_send_thread(void *opaque) p->zero_num =3D 0; =20 for (int i =3D 0; i < p->pages->num; i++) { - p->normal[p->normal_num] =3D p->pages->offset[i]; - p->normal_num++; + uint64_t offset =3D p->pages->offset[i]; + size_t page_size =3D qemu_target_page_size(); + if (use_zero_page && + buffer_is_zero(rb->host + offset, page_size)) { + p->zero[p->zero_num] =3D offset; + p->zero_num++; + ram_release_page(rb->idstr, offset); + } else { + p->normal[p->normal_num] =3D offset; + p->normal_num++; + } } =20 if (p->normal_num) { @@ -1117,6 +1148,13 @@ static void *multifd_recv_thread(void *opaque) } } =20 + for (int i =3D 0; i < p->zero_num; i++) { + void *page =3D p->host + p->zero[i]; + if (!buffer_is_zero(page, qemu_target_page_size())) { + memset(page, 0, qemu_target_page_size()); + } + } + if (flags & MULTIFD_FLAG_SYNC) { qemu_sem_post(&multifd_recv_state->sem_sync); qemu_sem_wait(&p->sem_sync); --=20 2.34.1