On Tue 14-11-17 14:28:11, David Rientjes wrote: [...] > > /proc/meminfo is paved with mistakes throughout the history. It pretends > > to give a good picture of the memory usage, yet we have many pointless > > entries while large consumers are not reflected at all in many case. > > > > Hugetlb data with that great details shouldn't have been exported in the > > first place when they reflect only one specific hugepage size. I would > > argue that if somebody went down to configure non-default hugetlb page > > sizes then checking for the sysfs stats would be an immediate place to > > look at. Anyway I can see that the cumulative information might be > > helpful for those who do not own the machine but merely debug an issue > > which is the primary usacase for the file. > > > > I agree in principle, but I think it's inevitable on projects that span > decades and accumulate features that evolve over time.
Yes, this is acceptable in earlier stages but I believe we have reached a mature state where we shouldn't repeat those mistakes. [...] > > > if (!hugepages_supported()) > > > return; > > > seq_printf(m, > > > @@ -2987,6 +2989,11 @@ void hugetlb_report_meminfo(struct seq_file *m) > > > h->resv_huge_pages, > > > h->surplus_huge_pages, > > > 1UL << (huge_page_order(h) + PAGE_SHIFT - 10)); > > > + > > > + for_each_hstate(h) > > > + total += (PAGE_SIZE << huge_page_order(h)) * h->nr_huge_pages; > > > > Please keep the total calculation consistent with what we have there > > already. > > > > Yeah, and I'm not sure if your comment eludes to this being racy, but it > would be better to store the default size for default_hstate during the > iteration to total the size for all hstates. I just meant to have the code consistent. I do not prefer one or other option. -- Michal Hocko SUSE Labs
