On Wed 22-06-16 19:57:17, Tetsuo Handa wrote: > Michal Hocko wrote: [...] > > That being said I guess the patch to try_to_freeze_tasks after > > oom_killer_disable should be simple enough to go for now and stable > > trees and we can come up with something less hackish later. I do not > > like the fact that oom_killer_disable doesn't act as a full "barrier" > > anymore. > > > > What do you think? > > I'm OK with calling try_to_freeze_tasks(true) again for Linux 4.6 and 4.7 > kernels.
OK, I will resend the patch CC Rafael and stable. > But if free memory is little such that oom_killer_disable() can not expect > TIF_MEMDIE > threads to clear TIF_MEMDIE by themselves (and therefore has to depend on the > OOM > reaper to clear TIF_MEMDIE on behalf of them after the OOM reaper reaped some > memory), > subsequent operations would be as well blocked waiting for an operation which > cannot > make any forward progress because it cannot proceed with an allocation. Then, > oom_killer_disable() returns false after some timeout (i.e. "do not try to > suspend > when the system is almost OOM") will be a safer reaction. Yes that is exactly what I meant by "oom_killer_disable has to give up" alternative. pm suspend already has a notion of timeout for back off and oom_killer_disable can use wait_even_timeout. But let's do that separately. -- Michal Hocko SUSE Labs
