Messages in this thread | | | Subject | Re: TTM page pool allocator | From | Michel Dänzer <> | Date | Wed, 22 Jul 2009 15:16:47 +0200 |
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On Tue, 2009-07-21 at 21:22 +0200, Jerome Glisse wrote: > On Tue, 2009-07-21 at 20:00 +0200, Jerome Glisse wrote: > > On Tue, 2009-07-21 at 19:34 +0200, Jerome Glisse wrote: > > > On Thu, 2009-06-25 at 17:53 +0200, Thomas Hellström wrote: > > > > > > > > 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, this never happen if > > > we don't call ttm_tt_populate and proceed with the remaining > > > of the cache transitioning functions > > > > > > As a workaround i will try to go through the pages tables and > > > transition existing pages. Do you have any idea for a better > > > plan ? > > > > > > Cheers, > > > Jerome > > > > My workaround ruin the whole idea of pool allocation what happens > > is that most bo get cache transition page per page. My thinking > > is that we should do the following: > > - is there is a least one page allocated then fully populate > > the object and do cache transition on all the pages. > > - otherwise update caching_state and leaves object unpopulated > > > > This needs that we some how reflect the fact that there is at least > > one page allocated, i am thinking to adding a new state for that : > > ttm_partialy_populated > > > > Thomas what do you think about that ? > > > > Cheers, > > Jerome > > Attached updated patch it doesn't introduce ttm_partialy_populated > but keep the populate call in cache transition. So far it seems to > work properly on AGP platform
Yeah, this one works for me as well.
> and helps quite a lot with performances.
Can't say I've noticed that however. How did you measure?
-- Earthling Michel Dänzer | http://www.vmware.com Libre software enthusiast | Debian, X and DRI developer -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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