The patch titled
Subject: mm: memcontrol: replace the loop with a list_for_each_entry()
has been added to the -mm tree. Its filename is
mm-memcontrol-replace-the-loop-with-a-list_for_each_entry.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-memcontrol-replace-the-loop-with-a-list_for_each_entry.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-memcontrol-replace-the-loop-with-a-list_for_each_entry.patch
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------------------------------------------------------
From: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Subject: mm: memcontrol: replace the loop with a list_for_each_entry()
The rule of list walk has gone since:
commit a9d5adeeb4b2 ("mm/memcontrol: allow to uncharge page without using page->lru field")
So remove the strange comment and replace the loop with a
list_for_each_entry().
There is only one caller of the uncharge_list(). So just fold it into
mem_cgroup_uncharge_list() and remove it.
Link: https://lkml.kernel.org/r/20210204163055.56080-1-songmuchun@xxxxxxxxxxxxx
Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Acked-by: Roman Gushchin <guro@xxxxxx>
Reviewed-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/memcontrol.c | 35 ++++++++---------------------------
1 file changed, 8 insertions(+), 27 deletions(-)
--- a/mm/memcontrol.c~mm-memcontrol-replace-the-loop-with-a-list_for_each_entry
+++ a/mm/memcontrol.c
@@ -6862,31 +6862,6 @@ static void uncharge_page(struct page *p
css_put(&ug->memcg->css);
}
-static void uncharge_list(struct list_head *page_list)
-{
- struct uncharge_gather ug;
- struct list_head *next;
-
- uncharge_gather_clear(&ug);
-
- /*
- * Note that the list can be a single page->lru; hence the
- * do-while loop instead of a simple list_for_each_entry().
- */
- next = page_list->next;
- do {
- struct page *page;
-
- page = list_entry(next, struct page, lru);
- next = page->lru.next;
-
- uncharge_page(page, &ug);
- } while (next != page_list);
-
- if (ug.memcg)
- uncharge_batch(&ug);
-}
-
/**
* mem_cgroup_uncharge - uncharge a page
* @page: page to uncharge
@@ -6918,11 +6893,17 @@ void mem_cgroup_uncharge(struct page *pa
*/
void mem_cgroup_uncharge_list(struct list_head *page_list)
{
+ struct uncharge_gather ug;
+ struct page *page;
+
if (mem_cgroup_disabled())
return;
- if (!list_empty(page_list))
- uncharge_list(page_list);
+ uncharge_gather_clear(&ug);
+ list_for_each_entry(page, page_list, lru)
+ uncharge_page(page, &ug);
+ if (ug.memcg)
+ uncharge_batch(&ug);
}
/**
_
Patches currently in -mm which might be from songmuchun@xxxxxxxxxxxxx are
mm-hugetlbfs-fix-cannot-migrate-the-fallocated-hugetlb-page.patch
mm-hugetlb-fix-a-race-between-freeing-and-dissolving-the-page.patch
mm-hugetlb-fix-a-race-between-isolating-and-freeing-page.patch
mm-hugetlb-remove-vm_bug_on_page-from-page_huge_active.patch
mm-migrate-do-not-migrate-hugetlb-page-whose-refcount-is-one.patch
mm-hugetlb-fix-missing-put_page-in-gather_surplus_pages.patch
mm-memcontrol-optimize-per-lruvec-stats-counter-memory-usage.patch
mm-memcontrol-fix-nr_anon_thps-accounting-in-charge-moving.patch
mm-memcontrol-convert-nr_anon_thps-account-to-pages.patch
mm-memcontrol-convert-nr_file_thps-account-to-pages.patch
mm-memcontrol-convert-nr_shmem_thps-account-to-pages.patch
mm-memcontrol-convert-nr_shmem_pmdmapped-account-to-pages.patch
mm-memcontrol-convert-nr_file_pmdmapped-account-to-pages.patch
mm-memcontrol-make-the-slab-calculation-consistent.patch
mm-memcontrol-replace-the-loop-with-a-list_for_each_entry.patch
hugetlb-convert-page_huge_active-hpagemigratable-flag-fix.patch
