Re: [PATCH v3] block: trace completion of all bios.

From: Christoph Hellwig
Date: Mon Mar 27 2017 - 13:15:11 EST


On Mon, Mar 27, 2017 at 08:49:57PM +1100, NeilBrown wrote:
> On Mon, Mar 27 2017, Christoph Hellwig wrote:
>
> > I don't really like the flag at all. I'd much prefer a __bio_endio
> > with a 'bool trace' flag. Also please remove the manual tracing in
> > dm.Ä. Once that is done I suspect we can also remove the
> > block_bio_complete export.
>
> Can you say why you don't like it?

It uses up a precious bit in the bio for something that should be state
that can be determined in the caller at compile time.