Re: [PATCH] mm: don't show nr_indirectly_reclaimable in /proc/vmstat

[Matthew Wilcox]

On Fri, Apr 27, 2018 at 11:41:31AM -0700, David Rientjes wrote:
> On Fri, 27 Apr 2018, Vlastimil Babka wrote:
> 
> > It was in the original thread, see e.g.
> > <08524819-14ef-81d0-fa90-d7af13c6b9d5@xxxxxxx>
> > 
> > However it will take some time to get that in mainline, and meanwhile
> > the current implementation does prevent a DOS. So I doubt it can be
> > fully reverted - as a compromise I just didn't want the counter to
> > become ABI. TBH though, other people at LSF/MM didn't seem concerned
> > that /proc/vmstat is an ABI that we can't change (i.e. counters have
> > been presumably removed in the past already).
> > 
> 
> What prevents this from being a simple atomic_t that gets added to in 
> __d_alloc(), subtracted from in __d_free_external_name(), and read in 
> si_mem_available() and __vm_enough_memory()?

I'd think you'd want one atomic_t per NUMA node at least ...