From: Fengguang Wu Date: Tue, 16 Oct 2007 08:24:36 +0000 (-0700) Subject: readahead: remove the limit max_sectors_kb imposed on max_readahead_kb X-Git-Tag: v2.6.24-rc1~1230 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f2e189827a914b66e435e68b1c9e37775cb995ed;p=linux-2.6 readahead: remove the limit max_sectors_kb imposed on max_readahead_kb 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 Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index d875673e76..a83823fcd7 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -3928,7 +3928,6 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count) 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; @@ -3937,14 +3936,6 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count) * 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);