On Tue, Jul 17, 2018 at 10:44:07AM +0200, Vlastimil Babka wrote: > On 07/02/2018 06:52 PM, Roman Gushchin wrote: > > On Sat, Jun 30, 2018 at 12:09:27PM +0200, Vlastimil Babka wrote: > >> On 06/29/2018 11:12 PM, Roman Gushchin wrote: > >>>> > >>>> The vmstat counter NR_INDIRECTLY_RECLAIMABLE_BYTES was introduced by commit > >>>> eb59254608bc ("mm: introduce NR_INDIRECTLY_RECLAIMABLE_BYTES") with the goal of > >>>> accounting objects that can be reclaimed, but cannot be allocated via a > >>>> SLAB_RECLAIM_ACCOUNT cache. This is now possible via kmalloc() with > >>>> __GFP_RECLAIMABLE flag, and the dcache external names user is converted. > >>>> > >>>> The counter is however still useful for accounting direct page allocations > >>>> (i.e. not slab) with a shrinker, such as the ION page pool. So keep it, and: > >>> > >>> Btw, it looks like I've another example of usefulness of this counter: > >>> dynamic per-cpu data. > >> > >> Hmm, but are those reclaimable? Most likely not in general? Do you have > >> examples that are? > > > > If these per-cpu data is something like per-cpu refcounters, > > which are using to manage reclaimable objects (e.g. cgroup css objects). > > Of course, they are not always reclaimable, but in certain states. > > BTW, seems you seem interested, could you provide some more formal > review as well? Others too. We don't need to cover all use cases > immediately, when the patchset is apparently stalled due to lack of > review. Thanks! Sure! The patchset looks sane at a first glance, but I need some time to dig deeper. Is v2 the final version? Thanks!