From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36112) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Ve2nd-0002As-1o for qemu-devel@nongnu.org; Wed, 06 Nov 2013 08:05:38 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Ve2nX-0004xS-14 for qemu-devel@nongnu.org; Wed, 06 Nov 2013 08:05:32 -0500 Received: from mx1.redhat.com ([209.132.183.28]:23771) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Ve2nW-0004xE-OW for qemu-devel@nongnu.org; Wed, 06 Nov 2013 08:05:26 -0500 From: Juan Quintela Date: Wed, 6 Nov 2013 14:04:35 +0100 Message-Id: <1383743088-8139-27-git-send-email-quintela@redhat.com> In-Reply-To: <1383743088-8139-1-git-send-email-quintela@redhat.com> References: <1383743088-8139-1-git-send-email-quintela@redhat.com> Subject: [Qemu-devel] [PATCH 26/39] memory: use find_next_bit() to find dirty bits List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: chegu_vinod@hp.com This operation is way faster than 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, -- 1.8.3.1