Signed-off-by: Wu Fengguang --- block/blk-core.c | 3 +-- fs/fuse/inode.c | 2 +- include/linux/mm.h | 3 +++ mm/backing-dev.c | 2 +- 4 files changed, 6 insertions(+), 4 deletions(-) --- linux.orig/block/blk-core.c 2010-01-30 17:38:48.000000000 +0800 +++ linux/block/blk-core.c 2010-01-30 18:10:01.000000000 +0800 @@ -498,8 +498,7 @@ struct request_queue *blk_alloc_queue_no q->backing_dev_info.unplug_io_fn = blk_backing_dev_unplug; q->backing_dev_info.unplug_io_data = q; - q->backing_dev_info.ra_pages = - (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE; + q->backing_dev_info.ra_pages = MAX_READAHEAD_PAGES; q->backing_dev_info.state = 0; q->backing_dev_info.capabilities = BDI_CAP_MAP_COPY; q->backing_dev_info.name = "block"; --- linux.orig/fs/fuse/inode.c 2010-01-30 17:38:48.000000000 +0800 +++ linux/fs/fuse/inode.c 2010-01-30 18:10:01.000000000 +0800 @@ -870,7 +870,7 @@ static int fuse_bdi_init(struct fuse_con int err; fc->bdi.name = "fuse"; - fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE; + fc->bdi.ra_pages = MAX_READAHEAD_PAGES; fc->bdi.unplug_io_fn = default_unplug_io_fn; /* fuse does it's own writeback accounting */ fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB; --- linux.orig/include/linux/mm.h 2010-01-30 18:09:58.000000000 +0800 +++ linux/include/linux/mm.h 2010-01-30 18:10:01.000000000 +0800 @@ -1187,6 +1187,9 @@ void task_dirty_inc(struct task_struct * #define VM_MAX_READAHEAD 512 /* kbytes */ #define VM_MIN_READAHEAD 32 /* kbytes (includes current page) */ +#define MAX_READAHEAD_PAGES (VM_MAX_READAHEAD*1024 / PAGE_CACHE_SIZE) +#define MIN_READAHEAD_PAGES DIV_ROUND_UP(VM_MIN_READAHEAD*1024, PAGE_CACHE_SIZE) + int force_page_cache_readahead(struct address_space *mapping, struct file *filp, pgoff_t offset, unsigned long nr_to_read); --- linux.orig/mm/backing-dev.c 2010-01-30 17:38:48.000000000 +0800 +++ linux/mm/backing-dev.c 2010-01-30 18:10:01.000000000 +0800 @@ -18,7 +18,7 @@ EXPORT_SYMBOL(default_unplug_io_fn); struct backing_dev_info default_backing_dev_info = { .name = "default", - .ra_pages = VM_MAX_READAHEAD * 1024 / PAGE_CACHE_SIZE, + .ra_pages = MAX_READAHEAD_PAGES, .state = 0, .capabilities = BDI_CAP_MAP_COPY, .unplug_io_fn = default_unplug_io_fn, -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/