From patchwork Wed Jan 30 10:35:54 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Orit Wasserman X-Patchwork-Id: 216821 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 6DDD72C0095 for ; Wed, 30 Jan 2013 21:35:21 +1100 (EST) Received: from localhost ([::1]:60397 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1U0V0h-00052b-C2 for incoming@patchwork.ozlabs.org; Wed, 30 Jan 2013 05:35:19 -0500 Received: from eggs.gnu.org ([208.118.235.92]:43838) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1U0V0N-0004tW-6H for qemu-devel@nongnu.org; Wed, 30 Jan 2013 05:35:00 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1U0V0L-0006FW-BC for qemu-devel@nongnu.org; Wed, 30 Jan 2013 05:34:59 -0500 Received: from mx1.redhat.com ([209.132.183.28]:54215) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1U0V0L-0006FK-0e for qemu-devel@nongnu.org; Wed, 30 Jan 2013 05:34:57 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r0UAYuro009384 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 30 Jan 2013 05:34:56 -0500 Received: from dhcp-1-120.tlv.redhat.com (vpn-200-67.tlv.redhat.com [10.35.200.67]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r0UAYiS3022984; Wed, 30 Jan 2013 05:34:51 -0500 From: Orit Wasserman To: qemu-devel@nongnu.org Date: Wed, 30 Jan 2013 12:35:54 +0200 Message-Id: <1359542158-30060-2-git-send-email-owasserm@redhat.com> In-Reply-To: <1359542158-30060-1-git-send-email-owasserm@redhat.com> References: <1359542158-30060-1-git-send-email-owasserm@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: aliguori@us.ibm.com, quintela@redhat.com, lcapitulino@redhat.com, Orit Wasserman , pbonzini@redhat.com Subject: [Qemu-devel] [PATCH 1/5] Move XBZRLE encoding code to a separate file to allow testing X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Signed-off-by: Orit Wasserman --- Makefile.objs | 2 +- savevm.c | 159 ----------------------------------------------------- xbzrle.c | 173 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 174 insertions(+), 160 deletions(-) create mode 100644 xbzrle.c diff --git a/Makefile.objs b/Makefile.objs index 68eb0ce..21e9c91 100644 --- a/Makefile.objs +++ b/Makefile.objs @@ -59,7 +59,7 @@ common-obj-$(CONFIG_LINUX) += fsdev/ common-obj-y += migration.o migration-tcp.o common-obj-y += qemu-char.o #aio.o common-obj-y += block-migration.o -common-obj-y += page_cache.o +common-obj-y += page_cache.o xbzrle.o common-obj-$(CONFIG_POSIX) += migration-exec.o migration-unix.o migration-fd.o diff --git a/savevm.c b/savevm.c index 304d1ef..b947e6a 100644 --- a/savevm.c +++ b/savevm.c @@ -2388,162 +2388,3 @@ void vmstate_register_ram_global(MemoryRegion *mr) { vmstate_register_ram(mr, NULL); } - -/* - page = zrun nzrun - | zrun nzrun page - - zrun = length - - nzrun = length byte... - - length = uleb128 encoded integer - */ -int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t *new_buf, int slen, - uint8_t *dst, int dlen) -{ - uint32_t zrun_len = 0, nzrun_len = 0; - int d = 0, i = 0; - long res, xor; - uint8_t *nzrun_start = NULL; - - g_assert(!(((uintptr_t)old_buf | (uintptr_t)new_buf | slen) % - sizeof(long))); - - while (i < slen) { - /* overflow */ - if (d + 2 > dlen) { - return -1; - } - - /* not aligned to sizeof(long) */ - res = (slen - i) % sizeof(long); - while (res && old_buf[i] == new_buf[i]) { - zrun_len++; - i++; - res--; - } - - /* word at a time for speed */ - if (!res) { - while (i < slen && - (*(long *)(old_buf + i)) == (*(long *)(new_buf + i))) { - i += sizeof(long); - zrun_len += sizeof(long); - } - - /* go over the rest */ - while (i < slen && old_buf[i] == new_buf[i]) { - zrun_len++; - i++; - } - } - - /* buffer unchanged */ - if (zrun_len == slen) { - return 0; - } - - /* skip last zero run */ - if (i == slen) { - return d; - } - - d += uleb128_encode_small(dst + d, zrun_len); - - zrun_len = 0; - nzrun_start = new_buf + i; - - /* overflow */ - if (d + 2 > dlen) { - return -1; - } - /* not aligned to sizeof(long) */ - res = (slen - i) % sizeof(long); - while (res && old_buf[i] != new_buf[i]) { - i++; - nzrun_len++; - res--; - } - - /* word at a time for speed, use of 32-bit long okay */ - if (!res) { - /* truncation to 32-bit long okay */ - long mask = (long)0x0101010101010101ULL; - while (i < slen) { - xor = *(long *)(old_buf + i) ^ *(long *)(new_buf + i); - if ((xor - mask) & ~xor & (mask << 7)) { - /* found the end of an nzrun within the current long */ - while (old_buf[i] != new_buf[i]) { - nzrun_len++; - i++; - } - break; - } else { - i += sizeof(long); - nzrun_len += sizeof(long); - } - } - } - - d += uleb128_encode_small(dst + d, nzrun_len); - /* overflow */ - if (d + nzrun_len > dlen) { - return -1; - } - memcpy(dst + d, nzrun_start, nzrun_len); - d += nzrun_len; - nzrun_len = 0; - } - - return d; -} - -int xbzrle_decode_buffer(uint8_t *src, int slen, uint8_t *dst, int dlen) -{ - int i = 0, d = 0; - int ret; - uint32_t count = 0; - - while (i < slen) { - - /* zrun */ - if ((slen - i) < 2) { - return -1; - } - - ret = uleb128_decode_small(src + i, &count); - if (ret < 0 || (i && !count)) { - return -1; - } - i += ret; - d += count; - - /* overflow */ - if (d > dlen) { - return -1; - } - - /* nzrun */ - if ((slen - i) < 2) { - return -1; - } - - ret = uleb128_decode_small(src + i, &count); - if (ret < 0 || !count) { - return -1; - } - i += ret; - - /* overflow */ - if (d + count > dlen || i + count > slen) { - return -1; - } - - memcpy(dst + d, src + i, count); - d += count; - i += count; - } - - return d; -} diff --git a/xbzrle.c b/xbzrle.c new file mode 100644 index 0000000..9dffa9d --- /dev/null +++ b/xbzrle.c @@ -0,0 +1,173 @@ +/* + * Xor Based Zero Run Length Encoding + * + * Copyright 2012 Red Hat, Inc. and/or its affiliates + * + * Authors: + * Orit Wasserman + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ +#include "qemu-common.h" +#include "include/migration/migration.h" + +/* + page = zrun nzrun + | zrun nzrun page + + zrun = length + + nzrun = length byte... + + length = uleb128 encoded integer + */ +int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t *new_buf, int slen, + uint8_t *dst, int dlen) +{ + uint32_t zrun_len = 0, nzrun_len = 0; + int d = 0, i = 0; + long res, xor; + uint8_t *nzrun_start = NULL; + + g_assert(!(((uintptr_t)old_buf | (uintptr_t)new_buf | slen) % + sizeof(long))); + + while (i < slen) { + /* overflow */ + if (d + 2 > dlen) { + return -1; + } + + /* not aligned to sizeof(long) */ + res = (slen - i) % sizeof(long); + while (res && old_buf[i] == new_buf[i]) { + zrun_len++; + i++; + res--; + } + + /* word at a time for speed */ + if (!res) { + while (i < slen && + (*(long *)(old_buf + i)) == (*(long *)(new_buf + i))) { + i += sizeof(long); + zrun_len += sizeof(long); + } + + /* go over the rest */ + while (i < slen && old_buf[i] == new_buf[i]) { + zrun_len++; + i++; + } + } + + /* buffer unchanged */ + if (zrun_len == slen) { + return 0; + } + + /* skip last zero run */ + if (i == slen) { + return d; + } + + d += uleb128_encode_small(dst + d, zrun_len); + + zrun_len = 0; + nzrun_start = new_buf + i; + + /* overflow */ + if (d + 2 > dlen) { + return -1; + } + /* not aligned to sizeof(long) */ + res = (slen - i) % sizeof(long); + while (res && old_buf[i] != new_buf[i]) { + i++; + nzrun_len++; + res--; + } + + /* word at a time for speed, use of 32-bit long okay */ + if (!res) { + /* truncation to 32-bit long okay */ + long mask = (long)0x0101010101010101ULL; + while (i < slen) { + xor = *(long *)(old_buf + i) ^ *(long *)(new_buf + i); + if ((xor - mask) & ~xor & (mask << 7)) { + /* found the end of an nzrun within the current long */ + while (old_buf[i] != new_buf[i]) { + nzrun_len++; + i++; + } + break; + } else { + i += sizeof(long); + nzrun_len += sizeof(long); + } + } + } + + d += uleb128_encode_small(dst + d, nzrun_len); + /* overflow */ + if (d + nzrun_len > dlen) { + return -1; + } + memcpy(dst + d, nzrun_start, nzrun_len); + d += nzrun_len; + nzrun_len = 0; + } + + return d; +} + +int xbzrle_decode_buffer(uint8_t *src, int slen, uint8_t *dst, int dlen) +{ + int i = 0, d = 0; + int ret; + uint32_t count = 0; + + while (i < slen) { + + /* zrun */ + if ((slen - i) < 2) { + return -1; + } + + ret = uleb128_decode_small(src + i, &count); + if (ret < 0 || (i && !count)) { + return -1; + } + i += ret; + d += count; + + /* overflow */ + if (d > dlen) { + return -1; + } + + /* nzrun */ + if ((slen - i) < 2) { + return -1; + } + + ret = uleb128_decode_small(src + i, &count); + if (ret < 0 || !count) { + return -1; + } + i += ret; + + /* overflow */ + if (d + count > dlen || i + count > slen) { + return -1; + } + + memcpy(dst + d, src + i, count); + d += count; + i += count; + } + + return d; +}