Re: [RFC PATCH] usb: storage: Add blockbuffer ptr to info struct of sddr09 driver

From: Jake Rice
Date: Fri May 09 2025 - 12:40:52 EST


On Fri, May 9, 2025 at 10:45 AM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Tue, May 06, 2025 at 03:15:31PM -0400, Jake Rice wrote:
> > Hi all,
> >
> > This patch updates the sddr09 driver to allocate a reusable block
> > buffer. Unfortunately, I don't have access to the SDDR-00 hardware
> > (which I know is pretty ancient), so I'm requesting testing from anyone who does.
> > Please let me now if the patch causes any issues or improves performance.
> >
> > Best,
> > Jake
> >
> > ---
> > Currently, upon every write the block buffer is allocated and freed which is
> > computationally expensive. With this implementation, a buffer pointer
> > is added as a member to the info struct and allocated when the card
> > information is read. The buffer is freed during desconstruction if
> > necessary.
>
> As Alan said, this is really slow hardware so I doubt allocating/free
> the buffer will even be noticeable. Why make this change at all if you
> don't have access to the hardware to test it?
>
> thanks,
>
> greg k-h
Alan and Greg,

I apologize, I was learning about the usb subsystem/usb drivers and
saw the TODO for this and figured it was a quick implementation. I
should have waited until I got the hardware before submitting the
change. It won't happen again.

In any case, thank you, I appreciate the feedback. I ordered the
device to test this. If I find a significant performance improvement,
I will re-submit.

Best,
Jake