lkml.org 
[lkml]   [2008]   [Mar]   [26]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
DateWed, 26 Mar 2008 06:29:11 +0100
FromIngo Molnar <>
SubjectRe: [Bug 10328] New: [regression] performance drop for glx
* Suresh Siddha <suresh.b.siddha@intel.com> wrote:

> fb drivers are using ioremap()/ioremap_nocache(), followed by mtrr_add 
> with WC attribute. Recent changes in page attribute code made both 
> ioremap()/ioremap_nocache() mappings as UC (instead of previous UC-). 
> This breaks the graphics performance, as the effective memory type is 
> UC instead of expected WC.
> 
> The correct way to fix this is to add ioremap_wc() (which uses UC- in 
> the absence of PAT kernel support and WC with PAT) and change all the 
> fb drivers to use this new ioremap_wc() API.
> 
> We can take this correct and longer route for post 2.6.25. For now, 
> revert back to the UC- behavior for ioremap/ioremap_nocache.

thanks Suresh, applied.

	Ingo


\
 
 \ /
  Last update: 2008-03-26 06:33    [from the cache]
©2003-2008