Re: [PATCH] null_blk: Register as a LightNVM device

[Jens Axboe]

On 11/12/2015 08:58 AM, Christoph Hellwig wrote:
> On Thu, Nov 12, 2015 at 08:54:48AM -0700, Jens Axboe wrote:
> > > 300 lines of boilerplate for just setting up a few request_queues seem
> > > wrong, can you show the actual patch you measured?
> >
> > I just took it from Matias' last posting:
> >
> > http://marc.info/?l=linux-kernel&m=144605858228534&w=2
>
> Well, that one has all these crazy completion methods which
> are of no use for a blk-mq driver, so it should really be
> compared without those.

So we can cut it down a bit, it's still going to be the same boilerplate 
code that null_blk has, even with just mq completions. If it ended up 
rewriting null_blk to be something else entirely or full of ifdef 
sprinkles, I'd agree. But for adding a hundred lines of code to be able 
to test lightnvm perf, I think it's  a no-brainer to just add it to 
null_blk and not have a separate module.

--
Jens Axboe

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/