On Mon, Mar 12, 2012 at 11:04:19AM +0800, Shaohua Li wrote:
> max_discard_sectors doesn't equal to max_sectors/max_hw_sectors. Without this,
> discard request merge might be ignored.
>
> Signed-off-by: Shaohua Li <shli@xxxxxxxxxxxx>
> ---
> block/blk-merge.c | 9 +++++++--
> include/linux/blkdev.h | 5 +++++
> 2 files changed, 12 insertions(+), 2 deletions(-)
>
> Index: linux/block/blk-merge.c
> ===================================================================
> --- linux.orig/block/blk-merge.c 2012-03-09 14:05:35.562062857 +0800
> +++ linux/block/blk-merge.c 2012-03-09 14:07:55.432062246 +0800
> @@ -228,13 +228,16 @@ no_merge:
> int ll_back_merge_fn(struct request_queue *q, struct request *req,
> struct bio *bio)
> {
> - unsigned short max_sectors;
> + unsigned int max_sectors;
>
> if (unlikely(req->cmd_type == REQ_TYPE_BLOCK_PC))
> max_sectors = queue_max_hw_sectors(q);
> else
> max_sectors = queue_max_sectors(q);
>
> + if (unlikely(req->cmd_flags & REQ_DISCARD))
> + max_sectors = queue_max_discard_sectors(q);
> +
May be make above check an "else if" condition above instead of starting
another "if" block.
Thanks
Vivek
--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
