Messages in this thread | | | Date | Wed, 26 Mar 2008 06:29:11 +0100 | From | Ingo Molnar <> | Subject | Re: [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
| |