Commit 49e50d27 authored Jun 03, 2020 by Johannes Weiner Committed by Linus Torvalds Jun 03, 2020

mm: memcontrol: prepare move_account for removal of private page type counters



When memcg uses the generic vmstat counters, it doesn't need to do
anything at charging and uncharging time.  It does, however, need to
migrate counts when pages move to a different cgroup in move_account.

Prepare the move_account function for the arrival of NR_FILE_PAGES,
NR_ANON_MAPPED, NR_ANON_THPS etc.  by having a branch for files and a
branch for anon, which can then divided into sub-branches.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Alex Shi <alex.shi@linux.alibaba.com>
Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Link: http://lkml.kernel.org/r/20200508183105.225460-8-hannes@cmpxchg.org


Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 9f762dbe

mm/memcontrol.c

+13 −12

Original line number	Diff line number	Diff line
		@@ -5434,7 +5434,6 @@ static int mem_cgroup_move_account(struct page *page,
		struct pglist_data *pgdat;
		unsigned int nr_pages = compound ? hpage_nr_pages(page) : 1;
		int ret;
		bool anon;

		VM_BUG_ON(from == to);
		VM_BUG_ON_PAGE(PageLRU(page), page);
		@@ -5452,25 +5451,27 @@ static int mem_cgroup_move_account(struct page *page,
		if (page->mem_cgroup != from)
		goto out_unlock;

		anon = PageAnon(page);

		pgdat = page_pgdat(page);
		from_vec = mem_cgroup_lruvec(from, pgdat);
		to_vec = mem_cgroup_lruvec(to, pgdat);

		lock_page_memcg(page);

		if (!anon && page_mapped(page)) {
		if (!PageAnon(page)) {
		if (page_mapped(page)) {
		__mod_lruvec_state(from_vec, NR_FILE_MAPPED, -nr_pages);
		__mod_lruvec_state(to_vec, NR_FILE_MAPPED, nr_pages);
		}

		if (!anon && PageDirty(page)) {
		if (PageDirty(page)) {
		struct address_space *mapping = page_mapping(page);

		if (mapping_cap_account_dirty(mapping)) {
		__mod_lruvec_state(from_vec, NR_FILE_DIRTY, -nr_pages);
		__mod_lruvec_state(to_vec, NR_FILE_DIRTY, nr_pages);
		__mod_lruvec_state(from_vec, NR_FILE_DIRTY,
		-nr_pages);
		__mod_lruvec_state(to_vec, NR_FILE_DIRTY,
		nr_pages);
		}
		}
		}