On Thu, Jan 4, 2024 at 12:04 PM Michal Koutný <mkoutny@xxxxxxxx> wrote: > > On Thu, Jan 04, 2024 at 11:29:43AM -0500, Pasha Tatashin <pasha.tatashin@xxxxxxxxxx> wrote: > > Thank you for taking a look at this. The two patches [1] [2] which add > > GFP_KERNEL_ACCOUNT were sent separate from this series at request of > > reviewers: > > Ah, I didn't catch that. > > Though, I mean the patch 02/10 calls iommu_alloc_pages() with GFP_KERNEL > (and not a passed gfp from iommu_map). > Then patch 09/10 accounts all iommu_alloc_pages() under NR_IOMMU_PAGES. > > I think there is a difference between what's shown NR_IOMMU_PAGES and > what will have __GFP_ACCOUNT because of that. > > I.e. is it the intention that this difference is not subject to > limiting? Yes, we will have a difference between GFP_ACCOUNT and what NR_IOMMU_PAGES shows. GFP_ACCOUNT is set only where it makes sense to charge to user processes, i.e. IOMMU Page Tables, but there more IOMMU shared data that should not really be charged to a specific process. The charged and uncharged data will be visible via /proc/vmstat nr_iommu_pages field. Pasha > > (Note: I'm not familiar with iommu code and moreover I'm only looking at > the two patch sets, not the complete code applied. So you may correct my > reasoning.) > > > Thanks, > Michal
