lkml.org 
[lkml]   [2016]   [Mar]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH 1/3] pfn_t: Change the encoding
From
On Fri, Mar 11, 2016 at 1:13 PM, Matthew Wilcox
<matthew.r.wilcox@intel.com> wrote:
> By moving the flag bits to the bottom, we encourage commonality
> between SGs with pages and those using pfn_t. We can also then insert
> a pfn_t into a radix tree, as it uses the same two bits for indirect &
> exceptional indicators.

It's not immediately clear to me what we gain with SG entry
commonality. The down side is that we lose the property that
pfn_to_pfn_t() is a nop. This was Dave's suggestion so that the
nominal case did not change the binary layout of a typical pfn.

Can we just bit swizzle a pfn_t on insertion/retrieval from the radix?

\
 
 \ /
  Last update: 2016-03-11 23:21    [W:0.071 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site