From patchwork Wed Oct 9 11:28:48 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juan Quintela X-Patchwork-Id: 281841 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 7557B2C00CA for ; Wed, 9 Oct 2013 22:40:02 +1100 (EST) Received: from localhost ([::1]:41332 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VTs7U-0002TL-Ei for incoming@patchwork.ozlabs.org; Wed, 09 Oct 2013 07:40:00 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42145) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VTrxN-0005dg-Eg for qemu-devel@nongnu.org; Wed, 09 Oct 2013 07:29:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VTrxH-0001Jy-An for qemu-devel@nongnu.org; Wed, 09 Oct 2013 07:29:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:25248) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VTrxH-0001Jp-2f for qemu-devel@nongnu.org; Wed, 09 Oct 2013 07:29:27 -0400 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r99BTP0q011389 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 9 Oct 2013 07:29:25 -0400 Received: from trasno.mitica (ovpn-113-116.phx2.redhat.com [10.3.113.116]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r99BSoPm015327; Wed, 9 Oct 2013 07:29:24 -0400 From: Juan Quintela To: qemu-devel@nongnu.org Date: Wed, 9 Oct 2013 13:28:48 +0200 Message-Id: <1381318130-10620-27-git-send-email-quintela@redhat.com> In-Reply-To: <1381318130-10620-1-git-send-email-quintela@redhat.com> References: <1381318130-10620-1-git-send-email-quintela@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.25 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: chegu_vinod@hp.com Subject: [Qemu-devel] [PATCH 26/28] memory: use find_next_bit() to find dirty bits 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 This operation is way faster that doing it bit by bit. Signed-off-by: Juan Quintela --- include/exec/memory-internal.h | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/include/exec/memory-internal.h b/include/exec/memory-internal.h index 0c1dbfa..5a5bc0d 100644 --- a/include/exec/memory-internal.h +++ b/include/exec/memory-internal.h @@ -44,18 +44,15 @@ static inline bool cpu_physical_memory_get_dirty(ram_addr_t start, ram_addr_t length, unsigned client) { - ram_addr_t addr, end; + unsigned long end, page, next; assert(client < DIRTY_MEMORY_NUM); - end = TARGET_PAGE_ALIGN(start + length); - start &= TARGET_PAGE_MASK; - for (addr = start; addr < end; addr += TARGET_PAGE_SIZE) { - if (test_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client])) { - return true; - } - } - return false; + end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS; + page = start >> TARGET_PAGE_BITS; + next = find_next_bit(ram_list.dirty_memory[client], end, page); + + return next < end; } static inline bool cpu_physical_memory_get_dirty_flag(ram_addr_t addr,