Re: [PATCH v2] xhci: Allocate the td array and urb_priv together.

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On Wed, Jan 08, 2014 at 03:29:31PM +0000, David Laight wrote:
> > From: 'David Cohen'
> ...
> > I actually don't know what's the regular range of 'td_cnt'. But what got my
> > attention was this comment from patch description:
> > 
> > "The only possible downside is for isochronous tranfers with 64 td
> > when the allocate is 8+4096 bytes (on 64bit systems) so requires
> > an additional page."
> 
> I wrote that just in case anyone knew that 64 td would be common.
> I suspect the typical number is much lower.

Ah :) That clears things up. Your patch won't influence kmalloc >
PAGE_SIZE in general. Although leaving the pointers in a different
struct preserves the possibility to call kmalloc multiple times when
xhci_td's allocation requires more than PAGE_SIZE.

But again, I'm not sure how often this happens, so I have not much
arguments in favor or against it.

Br, David Cohen

> 
> 	David
> 
> 
> 
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