From patchwork Thu Apr 1 07:47:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rao, Lei" X-Patchwork-Id: 12177497 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 6F50BC433ED for ; Thu, 1 Apr 2021 08:17:54 +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 BE59E61005 for ; Thu, 1 Apr 2021 08:17:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BE59E61005 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49466 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lRsWW-0003dC-Lo for qemu-devel@archiver.kernel.org; Thu, 01 Apr 2021 04:17:52 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34532) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lRsPz-0002dy-Ed for qemu-devel@nongnu.org; Thu, 01 Apr 2021 04:11:07 -0400 Received: from mga03.intel.com ([134.134.136.65]:13082) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lRsPx-00067j-HS for qemu-devel@nongnu.org; Thu, 01 Apr 2021 04:11:07 -0400 IronPort-SDR: yTabyjwHcxaD2qAc3XlCiWmxFBJEpGumf22cir5xCh+syofNmZ53RisH91w0YHVuLZgUA9qQkZ EkjDB+XflfEg== X-IronPort-AV: E=McAfee;i="6000,8403,9940"; a="192205138" X-IronPort-AV: E=Sophos;i="5.81,296,1610438400"; d="scan'208";a="192205138" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Apr 2021 01:11:03 -0700 IronPort-SDR: IodgwkLvwJE3FolasFpBHw8FIelyNgL8NL7YJCTBdNDmU6ltd1wHAcTBWzon6GyoZ7ujnQS9+5 fKTRkEIV4fWw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.81,296,1610438400"; d="scan'208";a="439119214" Received: from unknown (HELO localhost.localdomain.bj.intel.com) ([10.240.192.103]) by fmsmga004.fm.intel.com with ESMTP; 01 Apr 2021 01:11:00 -0700 From: leirao To: chen.zhang@intel.com, lizhijian@cn.fujitsu.com, jasowang@redhat.com, quintela@redhat.com, dgilbert@redhat.com, pbonzini@redhat.com, lukasstraub2@web.de Subject: [PATCH v5 08/10] Reduce the PVM stop time during Checkpoint Date: Thu, 1 Apr 2021 15:47:27 +0800 Message-Id: <1617263249-54501-9-git-send-email-lei.rao@intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1617263249-54501-1-git-send-email-lei.rao@intel.com> References: <1617263249-54501-1-git-send-email-lei.rao@intel.com> Received-SPF: pass client-ip=134.134.136.65; envelope-from=lei.rao@intel.com; helo=mga03.intel.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, 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: "Rao, Lei" , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: "Rao, Lei" When flushing memory from ram cache to ram during every checkpoint on secondary VM, we can copy continuous chunks of memory instead of 4096 bytes per time to reduce the time of VM stop during checkpoint. Signed-off-by: Lei Rao Reviewed-by: Dr. David Alan Gilbert --- migration/ram.c | 48 +++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 45 insertions(+), 3 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index c69a8e0..317fa4e 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -822,6 +822,41 @@ unsigned long migration_bitmap_find_dirty(RAMState *rs, RAMBlock *rb, return next; } +/* + * colo_bitmap_find_diry:find contiguous dirty pages from start + * + * Returns the page offset within memory region of the start of the contiguout + * dirty page + * + * @rs: current RAM state + * @rb: RAMBlock where to search for dirty pages + * @start: page where we start the search + * @num: the number of contiguous dirty pages + */ +static inline +unsigned long colo_bitmap_find_dirty(RAMState *rs, RAMBlock *rb, + unsigned long start, unsigned long *num) +{ + unsigned long size = rb->used_length >> TARGET_PAGE_BITS; + unsigned long *bitmap = rb->bmap; + unsigned long first, next; + + *num = 0; + + if (ramblock_is_ignored(rb)) { + return size; + } + + first = find_next_bit(bitmap, size, start); + if (first >= size) { + return first; + } + next = find_next_zero_bit(bitmap, size, first + 1); + assert(next >= first); + *num = next - first; + return first; +} + static inline bool migration_bitmap_clear_dirty(RAMState *rs, RAMBlock *rb, unsigned long page) @@ -3679,19 +3714,26 @@ void colo_flush_ram_cache(void) block = QLIST_FIRST_RCU(&ram_list.blocks); while (block) { - offset = migration_bitmap_find_dirty(ram_state, block, offset); + unsigned long num = 0; + offset = colo_bitmap_find_dirty(ram_state, block, offset, &num); if (((ram_addr_t)offset) << TARGET_PAGE_BITS >= block->used_length) { offset = 0; + num = 0; block = QLIST_NEXT_RCU(block, next); } else { - migration_bitmap_clear_dirty(ram_state, block, offset); + unsigned long i = 0; + + for (i = 0; i < num; i++) { + migration_bitmap_clear_dirty(ram_state, block, offset + i); + } dst_host = block->host + (((ram_addr_t)offset) << TARGET_PAGE_BITS); src_host = block->colo_cache + (((ram_addr_t)offset) << TARGET_PAGE_BITS); - memcpy(dst_host, src_host, TARGET_PAGE_SIZE); + memcpy(dst_host, src_host, TARGET_PAGE_SIZE * num); + offset += num; } } }