-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 09/26/2014 08:28 AM, Rob Clark wrote: > On Fri, Sep 26, 2014 at 6:45 AM, Thomas Hellstrom > <thellstrom@xxxxxxxxxx> wrote: >> On 09/26/2014 12:40 PM, Chuck Ebbert wrote: >>> On Fri, 26 Sep 2014 09:15:57 +0200 Thomas Hellstrom >>> <thellstrom@xxxxxxxxxx> wrote: >>> >>>> On 09/26/2014 01:52 AM, Peter Hurley wrote: >>>>> On 09/25/2014 03:35 PM, Chuck Ebbert wrote: >>>>>> There are six ttm patches queued for 3.16.4: >>>>>> >>>>>> drm-ttm-choose-a-pool-to-shrink-correctly-in-ttm_dma_pool_shrink_scan.patch >>>>>> >>>>>> drm-ttm-fix-handling-of-ttm_pl_flag_topdown-v2.patch >>>>>> drm-ttm-fix-possible-division-by-0-in-ttm_dma_pool_shrink_scan.patch >>>>>> >>>>>> drm-ttm-fix-possible-stack-overflow-by-recursive-shrinker-calls.patch >>>>>> drm-ttm-pass-gfp-flags-in-order-to-avoid-deadlock.patch >>>>>> drm-ttm-use-mutex_trylock-to-avoid-deadlock-inside-shrinker-functions.patch >>>>> >>>>>> Thanks for info, Chuck. >>>>> >>>>> Unfortunately, none of these fix TTM dma allocation doing >>>>> CMA dma allocation, which is the root problem. >>>>> >>>>> Regards, Peter Hurley >>>> The problem is not really in TTM but in CMA, There was a guy >>>> offering to fix this in the CMA code but I guess he didn't >>>> probably because he didn't receive any feedback. >>>> >>> Yeah, the "solution" to this problem seems to be "don't enable >>> CMA on x86". Maybe it should even be disabled in the config >>> system. >> Or, as previously suggested, don't use CMA for order 0 (single >> page) allocations.... > > On devices that actually need CMA pools to arrange for memory to be > in certain ranges, I think you probably do want to have order 0 > pages come from the CMA pool. > > Seems like disabling CMA on x86 (where it should be unneeded) is > the better way, IMO CMA has its uses on x86. For example, CMA is used to allocate 1GB huge pages. There may also be people with devices that do not scatter-gather, and need a large physically contiguous buffer, though there should be relatively few of those on x86. I suspect it makes most sense to do DMA allocations up to PAGE_ORDER through the normal allocator on x86, and only invoking CMA for larger allocations. - -- All rights reversed -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJUJV6lAAoJEM553pKExN6DjrQH/1N19Hp5FrJr+a3GpQDh6ouc YSBChxe+wG1h3OmcFGAG69tOK9XPw0oaV77ohwLxnvSv6BQZyi2CUIJvUdgSaOOx 8XYnn8VIIlMn4IKYmraAhSWT/gm3FkyDW7tckEdLV0NsrKeUcavCRHcLXxh41OBw XJboZyS3XvwF+scAwjHpWPxby1Byi0lZJizTAzI3xdlyVaM5Lio1xLvOW2MHY7dR h/ai8mfAAdQvnaHsFLoypBM/xYJqaUVU8IyCzhOeO86dUMy2xhD4vm/f9vSLuOju 4VYf7POuziNo1q2vJ8YcrThsAjB0Oiu9B5nDar471G3l1xN1zHQVw/RAnpNF9Kk= =iZlM -----END PGP SIGNATURE----- _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
