From: Johannes Weiner <hannes@xxxxxxxxxxx> Subject: mm: memcontrol: prepare uncharging for removal of private page type counters The uncharge batching code adds up the anon, file, kmem counts to determine the total number of pages to uncharge and references to drop. But the next patches will remove the anon and file counters. Maintain an aggregate nr_pages in the uncharge_gather struct. Link: http://lkml.kernel.org/r/20200508183105.225460-7-hannes@xxxxxxxxxxx Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Reviewed-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: "Kirill A. Shutemov" <kirill@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Roman Gushchin <guro@xxxxxx> Cc: Shakeel Butt <shakeelb@xxxxxxxxxx> Cc: Balbir Singh <bsingharora@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memcontrol.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) --- a/mm/memcontrol.c~mm-memcontrol-prepare-uncharging-for-removal-of-private-page-type-counters +++ a/mm/memcontrol.c @@ -6666,6 +6666,7 @@ int mem_cgroup_charge(struct page *page, struct uncharge_gather { struct mem_cgroup *memcg; + unsigned long nr_pages; unsigned long pgpgout; unsigned long nr_anon; unsigned long nr_file; @@ -6682,13 +6683,12 @@ static inline void uncharge_gather_clear static void uncharge_batch(const struct uncharge_gather *ug) { - unsigned long nr_pages = ug->nr_anon + ug->nr_file + ug->nr_kmem; unsigned long flags; if (!mem_cgroup_is_root(ug->memcg)) { - page_counter_uncharge(&ug->memcg->memory, nr_pages); + page_counter_uncharge(&ug->memcg->memory, ug->nr_pages); if (do_memsw_account()) - page_counter_uncharge(&ug->memcg->memsw, nr_pages); + page_counter_uncharge(&ug->memcg->memsw, ug->nr_pages); if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && ug->nr_kmem) page_counter_uncharge(&ug->memcg->kmem, ug->nr_kmem); memcg_oom_recover(ug->memcg); @@ -6700,16 +6700,18 @@ static void uncharge_batch(const struct __mod_memcg_state(ug->memcg, MEMCG_RSS_HUGE, -ug->nr_huge); __mod_memcg_state(ug->memcg, NR_SHMEM, -ug->nr_shmem); __count_memcg_events(ug->memcg, PGPGOUT, ug->pgpgout); - __this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, nr_pages); + __this_cpu_add(ug->memcg->vmstats_percpu->nr_page_events, ug->nr_pages); memcg_check_events(ug->memcg, ug->dummy_page); local_irq_restore(flags); if (!mem_cgroup_is_root(ug->memcg)) - css_put_many(&ug->memcg->css, nr_pages); + css_put_many(&ug->memcg->css, ug->nr_pages); } static void uncharge_page(struct page *page, struct uncharge_gather *ug) { + unsigned long nr_pages; + VM_BUG_ON_PAGE(PageLRU(page), page); if (!page->mem_cgroup) @@ -6729,13 +6731,12 @@ static void uncharge_page(struct page *p ug->memcg = page->mem_cgroup; } - if (!PageKmemcg(page)) { - unsigned int nr_pages = 1; + nr_pages = compound_nr(page); + ug->nr_pages += nr_pages; - if (PageTransHuge(page)) { - nr_pages = compound_nr(page); + if (!PageKmemcg(page)) { + if (PageTransHuge(page)) ug->nr_huge += nr_pages; - } if (PageAnon(page)) ug->nr_anon += nr_pages; else { @@ -6745,7 +6746,7 @@ static void uncharge_page(struct page *p } ug->pgpgout++; } else { - ug->nr_kmem += compound_nr(page); + ug->nr_kmem += nr_pages; __ClearPageKmemcg(page); } _
