diff options
author | Muchun Song <songmuchun@bytedance.com> | 2021-02-24 12:03:23 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-24 13:38:29 -0800 |
commit | 69473e5de87389be6c0fa4a5d574a50c8f904fb3 (patch) | |
tree | f03dc051fe9d9d90f2a058312f245d49b7d1bde4 /mm/rmap.c | |
parent | b0ba3bff3e7bb6b58bb248bdd2f3d8ad52fd10c3 (diff) | |
download | linux-69473e5de87389be6c0fa4a5d574a50c8f904fb3.tar.bz2 |
mm: memcontrol: convert NR_ANON_THPS account to pages
Currently we use struct per_cpu_nodestat to cache the vmstat counters,
which leads to inaccurate statistics especially THP vmstat counters. In
the systems with hundreds of processors it can be GBs of memory. For
example, for a 96 CPUs system, the threshold is the maximum number of 125.
And the per cpu counters can cache 23.4375 GB in total.
The THP page is already a form of batched addition (it will add 512 worth
of memory in one go) so skipping the batching seems like sensible.
Although every THP stats update overflows the per-cpu counter, resorting
to atomic global updates. But it can make the statistics more accuracy
for the THP vmstat counters.
So we convert the NR_ANON_THPS account to pages. This patch is consistent
with 8f182270dfec ("mm/swap.c: flush lru pvecs on compound page arrival").
Doing this also can make the unit of vmstat counters more unified.
Finally, the unit of the vmstat counters are pages, kB and bytes. The
B/KB suffix can tell us that the unit is bytes or kB. The rest which is
without suffix are pages.
Link: https://lkml.kernel.org/r/20201228164110.2838-3-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rafael. J. Wysocki <rafael@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pankaj Gupta <pankaj.gupta@cloud.ionos.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/rmap.c')
-rw-r--r-- | mm/rmap.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index 08c56aaf72eb..c4d5c63cfd29 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1144,7 +1144,7 @@ void do_page_add_anon_rmap(struct page *page, * disabled. */ if (compound) - __inc_lruvec_page_state(page, NR_ANON_THPS); + __mod_lruvec_page_state(page, NR_ANON_THPS, nr); __mod_lruvec_page_state(page, NR_ANON_MAPPED, nr); } @@ -1186,7 +1186,7 @@ void page_add_new_anon_rmap(struct page *page, if (hpage_pincount_available(page)) atomic_set(compound_pincount_ptr(page), 0); - __inc_lruvec_page_state(page, NR_ANON_THPS); + __mod_lruvec_page_state(page, NR_ANON_THPS, nr); } else { /* Anon THP always mapped first with PMD */ VM_BUG_ON_PAGE(PageTransCompound(page), page); @@ -1292,7 +1292,7 @@ static void page_remove_anon_compound_rmap(struct page *page) if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) return; - __dec_lruvec_page_state(page, NR_ANON_THPS); + __mod_lruvec_page_state(page, NR_ANON_THPS, -thp_nr_pages(page)); if (TestClearPageDoubleMap(page)) { /* |