From nobody Tue Dec 16 13:01:16 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 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 [208.118.235.17]) by mx.zohomail.com with SMTPS id 1539593374861470.0978331742134; Mon, 15 Oct 2018 01:49:34 -0700 (PDT) Received: from localhost ([::1]:51047 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gByZ8-0005cD-54 for importer@patchew.org; Mon, 15 Oct 2018 04:49:30 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45382) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gByWt-000476-Kf for qemu-devel@nongnu.org; Mon, 15 Oct 2018 04:47:13 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gByWr-000403-Qt for qemu-devel@nongnu.org; Mon, 15 Oct 2018 04:47:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44664) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1gByWq-0003pi-KA for qemu-devel@nongnu.org; Mon, 15 Oct 2018 04:47:09 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0869130001ED; Mon, 15 Oct 2018 08:46:57 +0000 (UTC) Received: from jason-ThinkPad-T430s.redhat.com (ovpn-12-138.pek2.redhat.com [10.72.12.138]) by smtp.corp.redhat.com (Postfix) with ESMTP id C458277707; Mon, 15 Oct 2018 08:46:54 +0000 (UTC) From: Jason Wang To: peter.maydell@linaro.org, qemu-devel@nongnu.org Date: Mon, 15 Oct 2018 16:46:09 +0800 Message-Id: <1539593186-32183-10-git-send-email-jasowang@redhat.com> In-Reply-To: <1539593186-32183-1-git-send-email-jasowang@redhat.com> References: <1539593186-32183-1-git-send-email-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.42]); Mon, 15 Oct 2018 08:46:57 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PULL 09/26] COLO: Flush memory data from ram cache X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jason Wang , zhanghailiang , Li Zhijian , Zhang Chen Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RDMRC_1 RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" From: Zhang Chen During the time of VM's running, PVM may dirty some pages, we will transfer PVM's dirty pages to SVM and store them into SVM's RAM cache at next checkp= oint time. So, the content of SVM's RAM cache will always be same with PVM's mem= ory after checkpoint. Instead of flushing all content of PVM's RAM cache into SVM's MEMORY, we do this in a more efficient way: Only flush any page that dirtied by PVM since last checkpoint. In this way, we can ensure SVM's memory same with PVM's. Besides, we must ensure flush RAM cache before load device state. Signed-off-by: zhanghailiang Signed-off-by: Li Zhijian Reviewed-by: Dr. David Alan Gilbert Signed-off-by: Jason Wang --- migration/ram.c | 37 +++++++++++++++++++++++++++++++++++++ migration/trace-events | 2 ++ 2 files changed, 39 insertions(+) diff --git a/migration/ram.c b/migration/ram.c index 404c8f0..477853d 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -3974,6 +3974,39 @@ static bool postcopy_is_running(void) return ps >=3D POSTCOPY_INCOMING_LISTENING && ps < POSTCOPY_INCOMING_E= ND; } =20 +/* + * Flush content of RAM cache into SVM's memory. + * Only flush the pages that be dirtied by PVM or SVM or both. + */ +static void colo_flush_ram_cache(void) +{ + RAMBlock *block =3D NULL; + void *dst_host; + void *src_host; + unsigned long offset =3D 0; + + trace_colo_flush_ram_cache_begin(ram_state->migration_dirty_pages); + rcu_read_lock(); + block =3D QLIST_FIRST_RCU(&ram_list.blocks); + + while (block) { + offset =3D migration_bitmap_find_dirty(ram_state, block, offset); + + if (offset << TARGET_PAGE_BITS >=3D block->used_length) { + offset =3D 0; + block =3D QLIST_NEXT_RCU(block, next); + } else { + migration_bitmap_clear_dirty(ram_state, block, offset); + dst_host =3D block->host + (offset << TARGET_PAGE_BITS); + src_host =3D block->colo_cache + (offset << TARGET_PAGE_BITS); + memcpy(dst_host, src_host, TARGET_PAGE_SIZE); + } + } + + rcu_read_unlock(); + trace_colo_flush_ram_cache_end(); +} + static int ram_load(QEMUFile *f, void *opaque, int version_id) { int flags =3D 0, ret =3D 0, invalid_flags =3D 0; @@ -4150,6 +4183,10 @@ static int ram_load(QEMUFile *f, void *opaque, int v= ersion_id) ret |=3D wait_for_decompress_done(); rcu_read_unlock(); trace_ram_load_complete(ret, seq_iter); + + if (!ret && migration_incoming_in_colo_state()) { + colo_flush_ram_cache(); + } return ret; } =20 diff --git a/migration/trace-events b/migration/trace-events index fa0ff3f..bd2d0cd 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -102,6 +102,8 @@ ram_dirty_bitmap_sync_start(void) "" ram_dirty_bitmap_sync_wait(void) "" ram_dirty_bitmap_sync_complete(void) "" ram_state_resume_prepare(uint64_t v) "%" PRId64 +colo_flush_ram_cache_begin(uint64_t dirty_pages) "dirty_pages %" PRIu64 +colo_flush_ram_cache_end(void) "" =20 # migration/migration.c await_return_path_close_on_source_close(void) "" --=20 2.5.0