On Thu, 2006-10-05 at 17:52 +0200, Thomas Hellström wrote: > Ben, > > I've implemented a version of the drm_mm code that unmaps ptes using > unmap_mapping_range, and remaps IO space using io_remap_pfn_range() for > a single page in nopage. This has the side effect that I need to double > check in nopage() after taking the object mutex that the pte in question > hasn't been populated by a racing nopage, which means I have to include > some page table walking code. I can see no obvious performance drops > from populating one pte at a time. > > This makes the need for an io-page aware nopage() or an > io_remap_pfn_range() that doesn't BUG on populated page tables quite > obvious. > > What is the status of the NOPAGE_RETRY mechanism in 2.6.19?
Patch just got in -mm, the return code changed to NOPAGE_REFAULT. It might still make it into 2.6.19. Regarding the change to io_remap_pfn_range(), I'm tempted to just provide a single routine to put in a single PTE that also does the double check of pte-present. I'll cook up something today hopefully as I want to experiment doing the exact same thing for SPE mappings on cell. Cheers, Ben. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV -- _______________________________________________ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
