Jerome Glisse wrote: > On Wed, 2009-07-22 at 10:27 +0200, Thomas Hellström wrote: > >> Jerome Glisse wrote: >> >>> On Thu, 2009-06-25 at 17:53 +0200, Thomas Hellström wrote: >>> >>> >>>> Jerome Glisse skrev: >>>> >>>> >>>>> Hi, >>>>> >>>>> Thomas i attach a reworked page pool allocator based on Dave works, >>>>> this one should be ok with ttm cache status tracking. It definitely >>>>> helps on AGP system, now the bottleneck is in mesa vertex's dma >>>>> allocation. >>>>> >>>>> Cheers, >>>>> Jerome >>>>> >>>>> >>>>> >>>> Hi, Jerome! >>>> In general it looks very good. Some things that need fixing: >>>> >>>> 1) We must have a way to hand back pages. I still not quite understand >>>> how the shrink callbacks work and whether they are applicable. Another >>>> scheme would be to free, say 1MB when we have at least 2MB available. >>>> >>>> 2) We should avoid including AGP headers if AGP is not configured. >>>> Either reimplement unmap_page_from_agp or map_page_into_agp or move them >>>> out from the AGP headers. We've hade complaints before from people with >>>> AGP free systems that the code doesn't compile. >>>> >>>> 3) Since we're allocating (and freeing) in batches we should use the >>>> set_pages_array() interface to avoid a global tlb flush per page. >>>> >>>> 4) We could now skip the ttm_tt_populate() in ttm_tt_set_caching, since >>>> it will always allocate cached pages and then transition them. >>>> >>>> >>>> >>> Okay 4) is bad, what happens (my brain is a bit meltdown so i might be >>> wrong) : >>> 1 - bo get allocated tt->state = unpopulated >>> 2 - bo is mapped few page are faulted tt->state = unpopulated >>> 3 - bo is cache transitioned but tt->state == unpopulated but >>> they are page which have been touch by the cpu so we need >>> to clflush them and transition them, >>> >> Right. >> >> >>> this never happen if >>> we don't call ttm_tt_populate and proceed with the remaining >>> of the cache transitioning functions >>> >>> >> Why can't we just skip ttm_tt_populate and proceed with the remaining of >> the cache transitioning functions? Then all pages currently allocated to >> the TTM will be transitioned. >> >> > > Because not all tt->pages entry have valid page some are null and thus > we have to go through the whole table and transition page per page. I > did that and quick benchmark showed that it's faster to fully populate > and fully transition. > > OK. That's probably sufficient for now.
/Thomas > Cheers, > Jerome > > ------------------------------------------------------------------------------ -- _______________________________________________ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
