On 2018-03-26 04:36 PM, Lucas Stach wrote: > Am Dienstag, den 30.01.2018, 11:28 +0100 schrieb Michal Hocko: >> On Tue 30-01-18 10:29:10, Michel Dänzer wrote: >>> On 2018-01-24 12:50 PM, Michal Hocko wrote: >>>> On Wed 24-01-18 12:23:10, Michel Dänzer wrote: >>>>> On 2018-01-24 12:01 PM, Michal Hocko wrote: >>>>>> On Wed 24-01-18 11:27:15, Michel Dänzer wrote: >>>> >>>> [...] >>>>>>> 2. If the OOM killer kills a process which is sharing BOs >>>>>>> with another >>>>>>> process, this should result in the other process dropping >>>>>>> its references >>>>>>> to the BOs as well, at which point the memory is released. >>>>>> >>>>>> OK. How exactly are those BOs mapped to the userspace? >>>>> >>>>> I'm not sure what you're asking. Userspace mostly uses a GEM >>>>> handle to >>>>> refer to a BO. There can also be userspace CPU mappings of the >>>>> BO's >>>>> memory, but userspace doesn't need CPU mappings for all BOs and >>>>> only >>>>> creates them as needed. >>>> >>>> OK, I guess you have to bear with me some more. This whole stack >>>> is a >>>> complete uknonwn. I am mostly after finding a boundary where you >>>> can >>>> charge the allocated memory to the process so that the oom killer >>>> can >>>> consider it. Is there anything like that? Except for the proposed >>>> file >>>> handle hack? >>> >>> How about the other way around: what APIs can we use to charge / >>> "uncharge" memory to a process? If we have those, we can experiment >>> with >>> different places to call them. >> >> add_mm_counter() and I would add a new counter e.g. MM_KERNEL_PAGES. > > So is anyone still working on this? This is hurting us bad enough that > I don't want to keep this topic rotting for another year. > > If no one is currently working on this I would volunteer to give the > simple "just account private, non-shared buffers in process RSS" a > spin. Sounds good. FWIW, I think shared buffers can also be easily handled by accounting them in each process which has a reference. But that's more of a detail, shouldn't make a big difference overall either way. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer
