From nobody Thu Nov 6 20:30:26 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.zoho.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; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1487735103000463.6148623324508; Tue, 21 Feb 2017 19:45:03 -0800 (PST) Received: from localhost ([::1]:49643 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cgNrP-0005rU-HB for importer@patchew.org; Tue, 21 Feb 2017 22:44:59 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42569) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cgNpN-0004i2-If for qemu-devel@nongnu.org; Tue, 21 Feb 2017 22:42:55 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cgNpJ-0002tT-EW for qemu-devel@nongnu.org; Tue, 21 Feb 2017 22:42:53 -0500 Received: from [45.249.212.189] (port=2400 helo=dggrg03-dlp.huawei.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.71) (envelope-from ) id 1cgNpI-0002pi-Qj for qemu-devel@nongnu.org; Tue, 21 Feb 2017 22:42:49 -0500 Received: from 172.30.72.53 (EHLO DGGEMM403-HUB.china.huawei.com) ([172.30.72.53]) by dggrg03-dlp.huawei.com (MOS 4.4.6-GA FastPath queued) with ESMTP id AIX52743; Wed, 22 Feb 2017 11:42:43 +0800 (CST) Received: from DGGEML401-HUB.china.huawei.com (10.3.17.32) by DGGEMM403-HUB.china.huawei.com (10.3.20.211) with Microsoft SMTP Server (TLS) id 14.3.301.0; Wed, 22 Feb 2017 11:42:40 +0800 Received: from localhost (10.177.24.212) by DGGEML401-HUB.china.huawei.com (10.3.17.32) with Microsoft SMTP Server id 14.3.301.0; Wed, 22 Feb 2017 11:42:31 +0800 From: zhanghailiang To: , , Date: Wed, 22 Feb 2017 11:42:10 +0800 Message-ID: <1487734936-43472-10-git-send-email-zhang.zhanghailiang@huawei.com> X-Mailer: git-send-email 2.7.2.windows.1 In-Reply-To: <1487734936-43472-1-git-send-email-zhang.zhanghailiang@huawei.com> References: <1487734936-43472-1-git-send-email-zhang.zhanghailiang@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.177.24.212] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.58AD08B3.00B6, ss=1, re=0.000, recu=0.000, reip=0.000, cl=1, cld=1, fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 284190f6ab331e9f6d011a955b26e4a0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.4.x-2.6.x [generic] [fuzzy] X-Received-From: 45.249.212.189 Subject: [Qemu-devel] [PATCH 09/15] COLO: Flush PVM's cached RAM into SVM's memory 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: xiecl.fnst@cn.fujitsu.com, zhanghailiang , lizhijian@cn.fujitsu.com, Juan Quintela Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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. Cc: Juan Quintela Signed-off-by: zhanghailiang Signed-off-by: Li Zhijian Reviewed-by: Dr. David Alan Gilbert --- include/migration/migration.h | 1 + migration/ram.c | 41 +++++++++++++++++++++++++++++++++++++++= ++ migration/trace-events | 2 ++ 3 files changed, 44 insertions(+) diff --git a/include/migration/migration.h b/include/migration/migration.h index 93c6148..ba5b97b 100644 --- a/include/migration/migration.h +++ b/include/migration/migration.h @@ -383,4 +383,5 @@ PostcopyState postcopy_state_set(PostcopyState new_stat= e); /* ram cache */ int colo_init_ram_cache(void); void colo_release_ram_cache(void); +void colo_flush_ram_cache(void); #endif diff --git a/migration/ram.c b/migration/ram.c index ed3b606..3f57fe0 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -2540,6 +2540,7 @@ static int ram_load(QEMUFile *f, void *opaque, int ve= rsion_id) * be atomic */ bool postcopy_running =3D postcopy_state_get() >=3D POSTCOPY_INCOMING_= LISTENING; + bool need_flush =3D false; =20 seq_iter++; =20 @@ -2574,6 +2575,7 @@ static int ram_load(QEMUFile *f, void *opaque, int ve= rsion_id) /* After going into COLO, we should load the Page into colo_ca= che */ if (ram_cache_enable) { host =3D colo_cache_from_block_offset(block, addr); + need_flush =3D true; } else { host =3D host_from_ram_block_offset(block, addr); } @@ -2668,6 +2670,10 @@ static int ram_load(QEMUFile *f, void *opaque, int v= ersion_id) wait_for_decompress_done(); rcu_read_unlock(); trace_ram_load_complete(ret, seq_iter); + + if (!ret && ram_cache_enable && need_flush) { + colo_flush_ram_cache(); + } return ret; } =20 @@ -2738,6 +2744,41 @@ void colo_release_ram_cache(void) rcu_read_unlock(); } =20 +/* + * Flush content of RAM cache into SVM's memory. + * Only flush the pages that be dirtied by PVM or SVM or both. + */ +void colo_flush_ram_cache(void) +{ + RAMBlock *block =3D NULL; + void *dst_host; + void *src_host; + ram_addr_t offset =3D 0; + + trace_colo_flush_ram_cache_begin(migration_dirty_pages); + rcu_read_lock(); + block =3D QLIST_FIRST_RCU(&ram_list.blocks); + + while (block) { + ram_addr_t ram_addr_abs; + offset =3D migration_bitmap_find_dirty(block, offset, &ram_addr_ab= s); + migration_bitmap_clear_dirty(ram_addr_abs); + + if (offset >=3D block->used_length) { + offset =3D 0; + block =3D QLIST_NEXT_RCU(block, next); + } else { + dst_host =3D block->host + offset; + src_host =3D block->colo_cache + offset; + memcpy(dst_host, src_host, TARGET_PAGE_SIZE); + } + } + + rcu_read_unlock(); + trace_colo_flush_ram_cache_end(); + assert(migration_dirty_pages =3D=3D 0); +} + static SaveVMHandlers savevm_ram_handlers =3D { .save_live_setup =3D ram_save_setup, .save_live_iterate =3D ram_save_iterate, diff --git a/migration/trace-events b/migration/trace-events index fa660e3..5d4cf80 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -71,6 +71,8 @@ migration_throttle(void) "" ram_load_postcopy_loop(uint64_t addr, int flags) "@%" PRIx64 " %x" ram_postcopy_send_discard_bitmap(void) "" ram_save_queue_pages(const char *rbname, size_t start, size_t len) "%s: st= art: %zx len: %zx" +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 1.8.3.1