Re: [PATCH v3 4/5] net: hpe: Add GXP UMAC Driver

[Hawkins, Nick]

Hi Andrew,

> > + length = 1514;
> > + }
> > +
> > + memset(pframe, 0, UMAC_MAX_FRAME_SIZE);
> > + memcpy(pframe, skb->data, length);


> Is this cached or uncached memory? uncached is expansive so you want
> to avoid touching it twice. Depending on how busy your cache is,
> touching it twice might cause it to expelled from L1 on the first
> write, so you could be writing to L2 twice for no reason. Do the math
> and calculate the tail space you need to zero.

> I would also suggest you look at the page pool code and use that for
> all you buffer handling. It is likely to be more efficient than what
> you have here.

Would this be the #include <linux/dmapool.h> library?

Thank you for the assistance,

-Nick Hawkins