From patchwork Thu Jun 6 01:31:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wei Yang X-Patchwork-Id: 10978191 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 86E051398 for ; Thu, 6 Jun 2019 01:34:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 71741286F3 for ; Thu, 6 Jun 2019 01:34:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 62ED728725; Thu, 6 Jun 2019 01:34:50 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id DABD8286F3 for ; Thu, 6 Jun 2019 01:34:49 +0000 (UTC) Received: from localhost ([127.0.0.1]:52642 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hYhIn-0007hk-5B for patchwork-qemu-devel@patchwork.kernel.org; Wed, 05 Jun 2019 21:34:49 -0400 Received: from eggs.gnu.org ([209.51.188.92]:40307) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hYhGK-0006Dm-Fr for qemu-devel@nongnu.org; Wed, 05 Jun 2019 21:32:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hYhGJ-0001kv-1Y for qemu-devel@nongnu.org; Wed, 05 Jun 2019 21:32:16 -0400 Received: from mga14.intel.com ([192.55.52.115]:32558) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hYhGI-0001j2-Pu for qemu-devel@nongnu.org; Wed, 05 Jun 2019 21:32:14 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Jun 2019 18:32:11 -0700 X-ExtLoop1: 1 Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by FMSMGA003.fm.intel.com with ESMTP; 05 Jun 2019 18:32:10 -0700 From: Wei Yang To: qemu-devel@nongnu.org Date: Thu, 6 Jun 2019 09:31:37 +0800 Message-Id: <20190606013138.13312-2-richardw.yang@linux.intel.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190606013138.13312-1-richardw.yang@linux.intel.com> References: <20190606013138.13312-1-richardw.yang@linux.intel.com> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 192.55.52.115 Subject: [Qemu-devel] [PATCH 1/2] migration/xbzrle: update cache and current_data in one place 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: Wei Yang , dgilbert@redhat.com, quintela@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP When we are not in the last_stage, we need to update the cache if page is not the same. Currently this procedure is scattered in two places and mixed with encoding status check. This patch extract this general step out to make the code a little bit easy to read. Signed-off-by: Wei Yang --- migration/ram.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index e9b40d636d..878cd8de7a 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1594,25 +1594,24 @@ static int save_xbzrle_page(RAMState *rs, uint8_t **current_data, encoded_len = xbzrle_encode_buffer(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE, XBZRLE.encoded_buf, TARGET_PAGE_SIZE); + + /* + * we need to update the data in the cache, in order to get the same data + */ + if (!last_stage && encoded_len != 0) { + memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE); + *current_data = prev_cached_page; + } + if (encoded_len == 0) { trace_save_xbzrle_page_skipping(); return 0; } else if (encoded_len == -1) { trace_save_xbzrle_page_overflow(); xbzrle_counters.overflow++; - /* update data in the cache */ - if (!last_stage) { - memcpy(prev_cached_page, *current_data, TARGET_PAGE_SIZE); - *current_data = prev_cached_page; - } return -1; } - /* we need to update the data in the cache, in order to get the same data */ - if (!last_stage) { - memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE); - } - /* Send XBZRLE based compressed page */ bytes_xbzrle = save_page_header(rs, rs->f, block, offset | RAM_SAVE_FLAG_XBZRLE);