From patchwork Mon Mar 1 08:21:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunkun Jiang X-Patchwork-Id: 12108969 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED60DC433E0 for ; Mon, 1 Mar 2021 08:23:50 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 4FCF464DD3 for ; Mon, 1 Mar 2021 08:23:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4FCF464DD3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:55470 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lGdqG-0002pm-Ce for qemu-devel@archiver.kernel.org; Mon, 01 Mar 2021 03:23:48 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:42842) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lGdok-0001ZY-RZ for qemu-devel@nongnu.org; Mon, 01 Mar 2021 03:22:14 -0500 Received: from szxga05-in.huawei.com ([45.249.212.191]:2945) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lGdog-0005W8-Aa for qemu-devel@nongnu.org; Mon, 01 Mar 2021 03:22:14 -0500 Received: from DGGEMS405-HUB.china.huawei.com (unknown [172.30.72.58]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4DptV269NNzMgSn; Mon, 1 Mar 2021 16:19:54 +0800 (CST) Received: from DESKTOP-6NKE0BC.china.huawei.com (10.174.185.210) by DGGEMS405-HUB.china.huawei.com (10.3.19.205) with Microsoft SMTP Server id 14.3.498.0; Mon, 1 Mar 2021 16:21:54 +0800 From: Kunkun Jiang To: David Edmondson , Juan Quintela , "Dr . David Alan Gilbert" , "open list:All patches CC here" Subject: [PATCH v2 1/3] migration/ram: Modify the code comment of ram_save_host_page() Date: Mon, 1 Mar 2021 16:21:30 +0800 Message-ID: <20210301082132.1107-2-jiangkunkun@huawei.com> X-Mailer: git-send-email 2.26.2.windows.1 In-Reply-To: <20210301082132.1107-1-jiangkunkun@huawei.com> References: <20210301082132.1107-1-jiangkunkun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.185.210] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.191; envelope-from=jiangkunkun@huawei.com; helo=szxga05-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Zenghui Yu , wanghaibin.wang@huawei.com, Keqian Zhu Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The ram_save_host_page() has been modified several times since its birth. But the comment hasn't been modified as it should be. It'd better to modify the comment to explain ram_save_host_page() more clearly. Signed-off-by: Keqian Zhu Signed-off-by: Kunkun Jiang --- migration/ram.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 72143da0ac..24967cb970 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1970,15 +1970,13 @@ static int ram_save_target_page(RAMState *rs, PageSearchStatus *pss, } /** - * ram_save_host_page: save a whole host page + * ram_save_host_page: save a whole host page or the rest of a RAMBlock * - * Starting at *offset send pages up to the end of the current host - * page. It's valid for the initial offset to point into the middle of - * a host page in which case the remainder of the hostpage is sent. - * Only dirty target pages are sent. Note that the host page size may - * be a huge page for this block. - * The saving stops at the boundary of the used_length of the block - * if the RAMBlock isn't a multiple of the host page size. + * Send dirty pages between pss->page and either the end of that page + * or the used_length of the RAMBlock, whichever is smaller. + * + * Note that if the host page is a huge page, pss->page may be in the + * middle of that page. * * Returns the number of pages written or negative on error * From patchwork Mon Mar 1 08:21:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunkun Jiang X-Patchwork-Id: 12108971 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3D3BC433E6 for ; Mon, 1 Mar 2021 08:23:50 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 3E3BA601FB for ; Mon, 1 Mar 2021 08:23:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3E3BA601FB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:55578 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lGdqH-0002sL-AD for qemu-devel@archiver.kernel.org; Mon, 01 Mar 2021 03:23:49 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:42840) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lGdok-0001ZE-0Z for qemu-devel@nongnu.org; Mon, 01 Mar 2021 03:22:14 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:3053) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lGdog-0005Xz-F6 for qemu-devel@nongnu.org; Mon, 01 Mar 2021 03:22:13 -0500 Received: from DGGEMS405-HUB.china.huawei.com (unknown [172.30.72.58]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4DptW10gDVzjSlX; Mon, 1 Mar 2021 16:20:45 +0800 (CST) Received: from DESKTOP-6NKE0BC.china.huawei.com (10.174.185.210) by DGGEMS405-HUB.china.huawei.com (10.3.19.205) with Microsoft SMTP Server id 14.3.498.0; Mon, 1 Mar 2021 16:21:57 +0800 From: Kunkun Jiang To: David Edmondson , Juan Quintela , "Dr . David Alan Gilbert" , "open list:All patches CC here" Subject: [PATCH v2 2/3] migration/ram: Modify ram_save_host_page() to match the comment Date: Mon, 1 Mar 2021 16:21:31 +0800 Message-ID: <20210301082132.1107-3-jiangkunkun@huawei.com> X-Mailer: git-send-email 2.26.2.windows.1 In-Reply-To: <20210301082132.1107-1-jiangkunkun@huawei.com> References: <20210301082132.1107-1-jiangkunkun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.185.210] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.32; envelope-from=jiangkunkun@huawei.com; helo=szxga06-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Zenghui Yu , wanghaibin.wang@huawei.com, Keqian Zhu Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" According to the comment, when the host page is a huge page, the migration_rate_limit() should be executed. If not, this function can be omitted to save time. Signed-off-by: Keqian Zhu Signed-off-by: Kunkun Jiang Reviewed-by: David Edmondson --- migration/ram.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/migration/ram.c b/migration/ram.c index 24967cb970..3a9115b6dc 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -2014,7 +2014,9 @@ static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss, pages += tmppages; pss->page++; /* Allow rate limiting to happen in the middle of huge pages */ - migration_rate_limit(); + if (pagesize_bits > 1) { + migration_rate_limit(); + } } while ((pss->page & (pagesize_bits - 1)) && offset_in_ramblock(pss->block, ((ram_addr_t)pss->page) << TARGET_PAGE_BITS)); From patchwork Mon Mar 1 08:21:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunkun Jiang X-Patchwork-Id: 12108973 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 96473C433E0 for ; Mon, 1 Mar 2021 08:24:21 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 30EF0601FB for ; Mon, 1 Mar 2021 08:24:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 30EF0601FB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57640 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lGdqm-0003jb-9T for qemu-devel@archiver.kernel.org; Mon, 01 Mar 2021 03:24:20 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:42804) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lGdoi-0001YZ-NL for qemu-devel@nongnu.org; Mon, 01 Mar 2021 03:22:13 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:3052) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lGdof-0005Xy-Oo for qemu-devel@nongnu.org; Mon, 01 Mar 2021 03:22:12 -0500 Received: from DGGEMS405-HUB.china.huawei.com (unknown [172.30.72.58]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4DptW10QlzzjSlK; Mon, 1 Mar 2021 16:20:45 +0800 (CST) Received: from DESKTOP-6NKE0BC.china.huawei.com (10.174.185.210) by DGGEMS405-HUB.china.huawei.com (10.3.19.205) with Microsoft SMTP Server id 14.3.498.0; Mon, 1 Mar 2021 16:21:59 +0800 From: Kunkun Jiang To: David Edmondson , Juan Quintela , "Dr . David Alan Gilbert" , "open list:All patches CC here" Subject: [PATCH v2 3/3] migration/ram: Optimize ram_save_host_page() Date: Mon, 1 Mar 2021 16:21:32 +0800 Message-ID: <20210301082132.1107-4-jiangkunkun@huawei.com> X-Mailer: git-send-email 2.26.2.windows.1 In-Reply-To: <20210301082132.1107-1-jiangkunkun@huawei.com> References: <20210301082132.1107-1-jiangkunkun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.185.210] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.32; envelope-from=jiangkunkun@huawei.com; helo=szxga06-in.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Zenghui Yu , wanghaibin.wang@huawei.com, Keqian Zhu Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Starting from pss->page, ram_save_host_page() will check every page and send the dirty pages up to the end of the current host page or the boundary of used_length of the block. If the host page size is a huge page, the step "check" will take a lot of time. This will improve performance to use migration_bitmap_find_dirty(). Signed-off-by: Keqian Zhu Signed-off-by: Kunkun Jiang --- migration/ram.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 3a9115b6dc..a1374db356 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1991,6 +1991,8 @@ static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss, int tmppages, pages = 0; size_t pagesize_bits = qemu_ram_pagesize(pss->block) >> TARGET_PAGE_BITS; + unsigned long hostpage_boundary = + QEMU_ALIGN_UP(pss->page + 1, pagesize_bits); unsigned long start_page = pss->page; int res; @@ -2002,7 +2004,7 @@ static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss, do { /* Check the pages is dirty and if it is send it */ if (!migration_bitmap_clear_dirty(rs, pss->block, pss->page)) { - pss->page++; + pss->page = migration_bitmap_find_dirty(rs, pss->block, pss->page); continue; } @@ -2012,16 +2014,16 @@ static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss, } pages += tmppages; - pss->page++; + pss->page = migration_bitmap_find_dirty(rs, pss->block, pss->page); /* Allow rate limiting to happen in the middle of huge pages */ if (pagesize_bits > 1) { migration_rate_limit(); } - } while ((pss->page & (pagesize_bits - 1)) && + } while ((pss->page < hostpage_boundary) && offset_in_ramblock(pss->block, ((ram_addr_t)pss->page) << TARGET_PAGE_BITS)); - /* The offset we leave with is the last one we looked at */ - pss->page--; + /* The offset we leave with is the min boundary of host page and block */ + pss->page = MIN(pss->page, hostpage_boundary) - 1; res = ram_save_release_protection(rs, pss, start_page); return (res < 0 ? res : pages);