On Tue, May 8, 2012 at 12:23 PM, Daniel Vetter <daniel@xxxxxxxx> wrote: > On Tue, May 08, 2012 at 08:25:38AM -0700, Linus Torvalds wrote: >> On Mon, May 7, 2012 at 4:13 PM, Stéphane Marchesin <marcheu@xxxxxxxxxxxx> wrote: >> > >> > In the end, I came up with the ugly workaround of just leaking the >> > offending pages in shmem.c. >> >> Don't leak it. >> >> Instead, add it to some RCU list, and free it using RCU. Or some >> one-second timer or something. >> >> That kind of approach should guarantee that it >> >> (a) gets returned to the system >> >> but >> >> (b) the returning to the system gets delayed sufficiently that if the >> i915 driver is doing lots of allocations it will be getting other >> pages. >> >> Hmm? > > The problem is also that this only affects Sandybdrige gpus, so we'd need > to funnel this down to shmfs somehow ... Rob Clarke from Linaro will be > working on a gemfs to make backing storage allocation more flexible - they > need that to support some arm gpus. That way round we wouldn't need to put > some ugly drm/i915 stuff into core shmfs. Rob? Well, a bit hand-wavey at this point, but the idea is to let the driver have control of the page allocation via 'struct address_space_operations'.. but otherwise work in a similar way as shmfs. Something like get_xip_mem() is almost what we want, except we don't want it to populate the pages, we don't want to force a kernel mapping, and shmem doesn't use it.. I suppose we still need a short term fix for i915, but at least it would only be temporary. BR, -R > -Daniel > -- > Daniel Vetter > Mail: daniel@xxxxxxxx > Mobile: +41 (0)79 365 57 48 > _______________________________________________ > dri-devel mailing list > dri-devel@xxxxxxxxxxxxxxxxxxxxx > http://lists.freedesktop.org/mailman/listinfo/dri-devel _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
