From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50787) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W2lW3-0002k0-Tx for qemu-devel@nongnu.org; Mon, 13 Jan 2014 12:41:41 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1W2lVx-00072R-60 for qemu-devel@nongnu.org; Mon, 13 Jan 2014 12:41:35 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43730) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1W2lVw-00071G-UB for qemu-devel@nongnu.org; Mon, 13 Jan 2014 12:41:29 -0500 From: Juan Quintela Date: Mon, 13 Jan 2014 18:40:21 +0100 Message-Id: <1389634834-24181-37-git-send-email-quintela@redhat.com> In-Reply-To: <1389634834-24181-1-git-send-email-quintela@redhat.com> References: <1389634834-24181-1-git-send-email-quintela@redhat.com> Subject: [Qemu-devel] [PATCH 36/49] 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: anthony@codemonkey.ws This operation is way faster than doing it bit by bit. Signed-off-by: Juan Quintela Reviewed-by: Eric Blake Reviewed-by: Orit Wasserman --- include/exec/memory-internal.h | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/include/exec/memory-internal.h b/include/exec/memory-internal.h index c04a92a..b017c2e 100644 --- a/include/exec/memory-internal.h +++ b/include/exec/memory-internal.h @@ -44,19 +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, -- 1.8.4.2