From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934632AbXGXCOo (ORCPT ); Mon, 23 Jul 2007 22:14:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761423AbXGXCMT (ORCPT ); Mon, 23 Jul 2007 22:12:19 -0400 Received: from smtp.ustc.edu.cn ([202.38.64.16]:40699 "HELO ustc.edu.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with SMTP id S1757664AbXGXCMN (ORCPT ); Mon, 23 Jul 2007 22:12:13 -0400 Message-ID: <385243123.51698@ustc.edu.cn> X-EYOUMAIL-SMTPAUTH: wfg@mail.ustc.edu.cn Message-Id: <20070724020042.882116065@mail.ustc.edu.cn> References: <20070724020009.677809022@mail.ustc.edu.cn> User-Agent: quilt/0.45-1 Date: Tue, 24 Jul 2007 10:00:17 +0800 From: Fengguang Wu To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Jens Axboe Subject: [PATCH 08/10] readahead: remove the limit max_sectors_kb imposed on max_readahead_kb Content-Disposition: inline; filename=remove-readahead-size-limit.patch Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Remove the size limit max_sectors_kb imposed on max_readahead_kb. The size restriction is unreasonable. Especially when max_sectors_kb cannot grow larger than max_hw_sectors_kb, which can be rather small for some disk drives. Cc: Jens Axboe Signed-off-by: Fengguang Wu Acked-by: Jens Axboe --- block/ll_rw_blk.c | 9 --------- 1 file changed, 9 deletions(-) --- linux-2.6.22-rc6-mm1.orig/block/ll_rw_blk.c +++ linux-2.6.22-rc6-mm1/block/ll_rw_blk.c @@ -3945,7 +3945,6 @@ queue_max_sectors_store(struct request_q max_hw_sectors_kb = q->max_hw_sectors >> 1, page_kb = 1 << (PAGE_CACHE_SHIFT - 10); ssize_t ret = queue_var_store(&max_sectors_kb, page, count); - int ra_kb; if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb) return -EINVAL; @@ -3954,14 +3953,6 @@ queue_max_sectors_store(struct request_q * values synchronously: */ spin_lock_irq(q->queue_lock); - /* - * Trim readahead window as well, if necessary: - */ - ra_kb = q->backing_dev_info.ra_pages << (PAGE_CACHE_SHIFT - 10); - if (ra_kb > max_sectors_kb) - q->backing_dev_info.ra_pages = - max_sectors_kb >> (PAGE_CACHE_SHIFT - 10); - q->max_sectors = max_sectors_kb << 1; spin_unlock_irq(q->queue_lock); --