On 2/6/20 2:31 PM, Mike Kravetz wrote: > On 2/3/20 3:22 PM, Mina Almasry wrote: >> Support MAP_NORESERVE accounting as part of the new counter. >> >> For each hugepage allocation, at allocation time we check if there is >> a reservation for this allocation or not. If there is a reservation for >> this allocation, then this allocation was charged at reservation time, >> and we don't re-account it. If there is no reserevation for this >> allocation, we charge the appropriate hugetlb_cgroup. >> >> The hugetlb_cgroup to uncharge for this allocation is stored in >> page[3].private. We use new APIs added in an earlier patch to set this >> pointer. > > Ah! That reminded me to look at the migration code. Turns out that none > of the existing cgroup information (page[2]) is being migrated today. That > is a bug. :( I'll confirm and fix in a patch separate from this series. > We will need to make sure that new information added by this series in page[3] > is also migrated. That would be in an earlier patch where the use of the > field is introduced. My appologies! cgroup information is migrated and you took care of it for new reservation information in patch 2. Please disregard that statement. -- Mike Kravetz