From patchwork Tue Mar 16 12:57:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunkun Jiang X-Patchwork-Id: 12142157 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,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 42654C433E0 for ; Tue, 16 Mar 2021 12:59:34 +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 9062A65053 for ; Tue, 16 Mar 2021 12:59:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9062A65053 Authentication-Results: mail.kernel.org; dmarc=fail (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]:45860 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lM9IK-0000S4-N8 for qemu-devel@archiver.kernel.org; Tue, 16 Mar 2021 08:59:32 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:49474) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lM9HC-0007rS-SD for qemu-devel@nongnu.org; Tue, 16 Mar 2021 08:58:22 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:4302) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lM9HA-000170-V1 for qemu-devel@nongnu.org; Tue, 16 Mar 2021 08:58:22 -0400 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4F0CvW6r3xzmXly; Tue, 16 Mar 2021 20:55:51 +0800 (CST) Received: from DESKTOP-6NKE0BC.china.huawei.com (10.174.185.210) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.498.0; Tue, 16 Mar 2021 20:58:04 +0800 From: Kunkun Jiang To: David Edmondson , Peter Xu , Juan Quintela , "Dr . David Alan Gilbert" , Andrey Gruzdev , =?utf-8?q?C=C3=A9dric_Le_Goa?= =?utf-8?q?ter?= , Alexey Romko , "open list:All patches CC here" Subject: [PATCH v4 1/2] migration/ram: Reduce unnecessary rate limiting Date: Tue, 16 Mar 2021 20:57:15 +0800 Message-ID: <20210316125716.1243-2-jiangkunkun@huawei.com> X-Mailer: git-send-email 2.26.2.windows.1 In-Reply-To: <20210316125716.1243-1-jiangkunkun@huawei.com> References: <20210316125716.1243-1-jiangkunkun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.185.210] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.190; envelope-from=jiangkunkun@huawei.com; helo=szxga04-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=0.001, 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" When the host page is a huge page and something is sent in the current iteration, migration_rate_limit() should be executed. If not, it can be omitted. Signed-off-by: Keqian Zhu Signed-off-by: Kunkun Jiang Reviewed-by: David Edmondson --- migration/ram.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 72143da0ac..3eb5b0d7a7 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -2015,8 +2015,13 @@ 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(); + /* + * Allow rate limiting to happen in the middle of huge pages if + * something is sent in the current iteration. + */ + if (pagesize_bits > 1 && tmppages > 0) { + 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 Mar 16 12:57:16 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kunkun Jiang X-Patchwork-Id: 12142191 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,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 32036C433E0 for ; Tue, 16 Mar 2021 13:02:48 +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 A02C86505C for ; Tue, 16 Mar 2021 13:02:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A02C86505C Authentication-Results: mail.kernel.org; dmarc=fail (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]:49696 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lM9LP-0002HK-8d for qemu-devel@archiver.kernel.org; Tue, 16 Mar 2021 09:02:46 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:49464) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lM9HB-0007px-Kr for qemu-devel@nongnu.org; Tue, 16 Mar 2021 08:58:21 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:4303) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lM9H8-000171-L7 for qemu-devel@nongnu.org; Tue, 16 Mar 2021 08:58:21 -0400 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.60]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4F0CvX02jFzmYB0; Tue, 16 Mar 2021 20:55:52 +0800 (CST) Received: from DESKTOP-6NKE0BC.china.huawei.com (10.174.185.210) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.498.0; Tue, 16 Mar 2021 20:58:07 +0800 From: Kunkun Jiang To: David Edmondson , Peter Xu , Juan Quintela , "Dr . David Alan Gilbert" , Andrey Gruzdev , =?utf-8?q?C=C3=A9dric_Le_Goa?= =?utf-8?q?ter?= , Alexey Romko , "open list:All patches CC here" Subject: [PATCH v4 2/2] migration/ram: Optimize ram_save_host_page() Date: Tue, 16 Mar 2021 20:57:16 +0800 Message-ID: <20210316125716.1243-3-jiangkunkun@huawei.com> X-Mailer: git-send-email 2.26.2.windows.1 In-Reply-To: <20210316125716.1243-1-jiangkunkun@huawei.com> References: <20210316125716.1243-1-jiangkunkun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.174.185.210] X-CFilter-Loop: Reflected Received-SPF: pass client-ip=45.249.212.190; envelope-from=jiangkunkun@huawei.com; helo=szxga04-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=0.001, 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. It will improve performance to use migration_bitmap_find_dirty(). Tested on Kunpeng 920; VM parameters: 1U 4G (page size 1G) The time of ram_save_host_page() in the last round of ram saving: before optimize: 9250us after optimize: 34us Signed-off-by: Keqian Zhu Signed-off-by: Kunkun Jiang Reviewed-by: Peter Xu --- migration/ram.c | 39 +++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 20 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 3eb5b0d7a7..1d9c24aa85 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1993,6 +1993,8 @@ 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; @@ -2003,30 +2005,27 @@ 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; - } - - tmppages = ram_save_target_page(rs, pss, last_stage); - if (tmppages < 0) { - return tmppages; - } + if (migration_bitmap_clear_dirty(rs, pss->block, pss->page)) { + tmppages = ram_save_target_page(rs, pss, last_stage); + if (tmppages < 0) { + return tmppages; + } - pages += tmppages; - pss->page++; - /* - * Allow rate limiting to happen in the middle of huge pages if - * something is sent in the current iteration. - */ - if (pagesize_bits > 1 && tmppages > 0) { - migration_rate_limit(); + pages += tmppages; + /* + * Allow rate limiting to happen in the middle of huge pages if + * something is sent in the current iteration. + */ + if (pagesize_bits > 1 && tmppages > 0) { + migration_rate_limit(); + } } - } while ((pss->page & (pagesize_bits - 1)) && + 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);