Re: [dm-devel] [PATCH v3 04/26] block: Refactor blk_update_request()

[Vivek Goyal <vgoyal redhat com>]

On Mon, Sep 24, 2012 at 03:34:44PM -0700, Kent Overstreet wrote:
> Converts it to use bio_advance(), simplifying it quite a bit in the
> process.
> 
> Note that req_bio_endio() now always calls bio_advance() - which means
> it always loops over the biovec, not just on partial completions. Don't
> expect it to affect performance, but worth noting.
> 
> Tested it by forcing partial updates, and dumping before and after on
> various bio/bvec fields when doing a partial update.

Kent,

In general, have you tested all these changes with FLUSH and DISCARD 
bios/requests. Some of the code paths tend to break down because of these
special bios don't have payload.

Thanks
Vivek