From patchwork Fri Jul 12 14:31:53 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juan Quintela X-Patchwork-Id: 11042359 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 2374F112C for ; Fri, 12 Jul 2019 14:32:27 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1253C28BF4 for ; Fri, 12 Jul 2019 14:32:27 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 065DE28C1C; Fri, 12 Jul 2019 14:32:27 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A2FA528BF4 for ; Fri, 12 Jul 2019 14:32:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727320AbfGLOcZ (ORCPT ); Fri, 12 Jul 2019 10:32:25 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51496 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727253AbfGLOcZ (ORCPT ); Fri, 12 Jul 2019 10:32:25 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 5B44558E33; Fri, 12 Jul 2019 14:32:25 +0000 (UTC) Received: from localhost.localdomain (unknown [10.36.118.16]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4AEF560920; Fri, 12 Jul 2019 14:32:23 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Cc: Laurent Vivier , Richard Henderson , Paolo Bonzini , kvm@vger.kernel.org, "Dr. David Alan Gilbert" , Juan Quintela , Thomas Huth , Wei Yang Subject: [PULL 05/19] migration/xbzrle: update cache and current_data in one place Date: Fri, 12 Jul 2019 16:31:53 +0200 Message-Id: <20190712143207.4214-6-quintela@redhat.com> In-Reply-To: <20190712143207.4214-1-quintela@redhat.com> References: <20190712143207.4214-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Fri, 12 Jul 2019 14:32:25 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Wei Yang 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 Reviewed-by: Juan Quintela Reviewed-by: Dr. David Alan Gilbert Message-Id: <20190610004159.20966-1-richardw.yang@linux.intel.com> Signed-off-by: Juan Quintela --- migration/ram.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 74c9306c78..d3d72b6f4f 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -1585,25 +1585,30 @@ 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); + + /* + * Update the cache contents, so that it corresponds to the data + * sent, in all cases except where we skip the page. + */ + if (!last_stage && encoded_len != 0) { + memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE); + /* + * In the case where we couldn't compress, ensure that the caller + * sends the data from the cache, since the guest might have + * changed the RAM since we copied it. + */ + *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);