From patchwork Tue Feb 23 02:16:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunkun Jiang X-Patchwork-Id: 12099747 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 4C4E2C433E0 for ; Tue, 23 Feb 2021 02:21:39 +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 C344064E25 for ; Tue, 23 Feb 2021 02:21:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C344064E25 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]:52406 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lENKT-0004pi-UK for qemu-devel@archiver.kernel.org; Mon, 22 Feb 2021 21:21:37 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:51994) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lENGt-0001ul-Ob for qemu-devel@nongnu.org; Mon, 22 Feb 2021 21:17:55 -0500 Received: from szxga05-in.huawei.com ([45.249.212.191]:3484) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lENGs-0006Um-15 for qemu-devel@nongnu.org; Mon, 22 Feb 2021 21:17:55 -0500 Received: from DGGEMS410-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4Dl2j20fP0zjRL8; Tue, 23 Feb 2021 10:16:06 +0800 (CST) Received: from DESKTOP-6NKE0BC.china.huawei.com (10.174.185.210) by DGGEMS410-HUB.china.huawei.com (10.3.19.210) with Microsoft SMTP Server id 14.3.498.0; Tue, 23 Feb 2021 10:17:29 +0800 From: Kunkun Jiang To: Juan Quintela , "Dr . David Alan Gilbert" , "open list:All patches CC here" Subject: [PATCH 1/3] migration/ram: Modify the code comment of ram_save_host_page() Date: Tue, 23 Feb 2021 10:16:43 +0800 Message-ID: <20210223021646.500-2-jiangkunkun@huawei.com> X-Mailer: git-send-email 2.26.2.windows.1 In-Reply-To: <20210223021646.500-1-jiangkunkun@huawei.com> References: <20210223021646.500-1-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 | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 72143da0ac..fc49c3f898 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1970,15 +1970,16 @@ 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 block * - * 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. + * Starting at pss->page send pages up to the end of the current host + * page or the boundary of used_length of the block (if the RAMBlock + * isn't a multiple of the host page size). The min one is selected. + * Only dirty target pages are sent. + * + * Note that the host page size may be a huge page for this block, 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. * * Returns the number of pages written or negative on error * From patchwork Tue Feb 23 02:16:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunkun Jiang X-Patchwork-Id: 12099729 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 EF072C433E0 for ; Tue, 23 Feb 2021 02:21:36 +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 55CF36146D for ; Tue, 23 Feb 2021 02:21:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 55CF36146D 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]:52248 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lENKR-0004gI-99 for qemu-devel@archiver.kernel.org; Mon, 22 Feb 2021 21:21:35 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:51982) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lENGr-0001r4-QR for qemu-devel@nongnu.org; Mon, 22 Feb 2021 21:17:53 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:2653) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lENGo-0006Wu-SN for qemu-devel@nongnu.org; Mon, 22 Feb 2021 21:17:53 -0500 Received: from DGGEMS410-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4Dl2j735qTz7pKx; Tue, 23 Feb 2021 10:16:11 +0800 (CST) Received: from DESKTOP-6NKE0BC.china.huawei.com (10.174.185.210) by DGGEMS410-HUB.china.huawei.com (10.3.19.210) with Microsoft SMTP Server id 14.3.498.0; Tue, 23 Feb 2021 10:17:34 +0800 From: Kunkun Jiang To: Juan Quintela , "Dr . David Alan Gilbert" , "open list:All patches CC here" Subject: [PATCH 2/3] migration/ram: Modify ram_save_host_page() to match the comment Date: Tue, 23 Feb 2021 10:16:44 +0800 Message-ID: <20210223021646.500-3-jiangkunkun@huawei.com> X-Mailer: git-send-email 2.26.2.windows.1 In-Reply-To: <20210223021646.500-1-jiangkunkun@huawei.com> References: <20210223021646.500-1-jiangkunkun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.185.210] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.35; envelope-from=jiangkunkun@huawei.com; helo=szxga07-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_H4=0.001, RCVD_IN_MSPIKE_WL=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" 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 --- migration/ram.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/migration/ram.c b/migration/ram.c index fc49c3f898..c7e18dc2fc 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -2017,7 +2017,9 @@ 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 Tue Feb 23 02:16:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunkun Jiang X-Patchwork-Id: 12099727 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 303F5C433E6 for ; Tue, 23 Feb 2021 02:18:56 +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 82DD064E00 for ; Tue, 23 Feb 2021 02:18:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 82DD064E00 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]:48024 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lENHq-0002jm-9q for qemu-devel@archiver.kernel.org; Mon, 22 Feb 2021 21:18:54 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:51980) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lENGq-0001pq-OP for qemu-devel@nongnu.org; Mon, 22 Feb 2021 21:17:52 -0500 Received: from szxga07-in.huawei.com ([45.249.212.35]:2652) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lENGo-0006Wv-JO for qemu-devel@nongnu.org; Mon, 22 Feb 2021 21:17:52 -0500 Received: from DGGEMS410-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4Dl2j72t3qz7nm3; Tue, 23 Feb 2021 10:16:11 +0800 (CST) Received: from DESKTOP-6NKE0BC.china.huawei.com (10.174.185.210) by DGGEMS410-HUB.china.huawei.com (10.3.19.210) with Microsoft SMTP Server id 14.3.498.0; Tue, 23 Feb 2021 10:17:39 +0800 From: Kunkun Jiang To: Juan Quintela , "Dr . David Alan Gilbert" , "open list:All patches CC here" Subject: [PATCH 3/3] migration/ram: Optimize ram_save_host_page() Date: Tue, 23 Feb 2021 10:16:45 +0800 Message-ID: <20210223021646.500-4-jiangkunkun@huawei.com> X-Mailer: git-send-email 2.26.2.windows.1 In-Reply-To: <20210223021646.500-1-jiangkunkun@huawei.com> References: <20210223021646.500-1-jiangkunkun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.185.210] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.35; envelope-from=jiangkunkun@huawei.com; helo=szxga07-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_H4=0.001, RCVD_IN_MSPIKE_WL=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" 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 | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index c7e18dc2fc..c7a2350198 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1994,6 +1994,8 @@ 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; @@ -2005,8 +2007,7 @@ 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++; - continue; + goto find_next; } tmppages = ram_save_target_page(rs, pss, last_stage); @@ -2015,16 +2016,17 @@ 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 */ if (pagesize_bits > 1) { migration_rate_limit(); } - } while ((pss->page & (pagesize_bits - 1)) && +find_next: + pss->page = migration_bitmap_find_dirty(rs, pss->block, pss->page); + } 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);