[PATCH 03/11] mm: don't pass "enum lru_list" to lru list addition functions

Yu Zhao
2020-12-07T22:11:04Z

The "enum lru_list" parameter to add_page_to_lru_list() and
add_page_to_lru_list_tail() is redundant in the sense that it can
be extracted from the "struct page" parameter by page_lru().

A caveat is that we need to make sure PageActive() or
PageUnevictable() is correctly set or cleared before calling
these two functions. And they are indeed.

Signed-off-by: Yu Zhao <yuzhao@google.com>
---
include/linux/mm_inline.h | 8 ++++++--
mm/swap.c | 15 +++++++--------
mm/vmscan.c | 6 ++----
3 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h
index 2889741f450a..130ba3201d3f 100644
--- a/include/linux/mm_inline.h
+++ b/include/linux/mm_inline.h
@@ -106,15 +106,19 @@ static __always_inline enum lru_list page_lru(struct page *page)
}

static __always_inline void add_page_to_lru_list(struct page *page,
- struct lruvec *lruvec, enum lru_list lru)
+ struct lruvec *lruvec)
{
+ enum lru_list lru = page_lru(page);
+
update_lru_size(lruvec, lru, page_zonenum(page), thp_nr_pages(page));
list_add(&page->lru, &lruvec->lists[lru]);
}

static __always_inline void add_page_to_lru_list_tail(struct page *page,
- struct lruvec *lruvec, enum lru_list lru)
+ struct lruvec *lruvec)
{
+ enum lru_list lru = page_lru(page);
+
update_lru_size(lruvec, lru, page_zonenum(page), thp_nr_pages(page));
list_add_tail(&page->lru, &lruvec->lists[lru]);
}
diff --git a/mm/swap.c b/mm/swap.c
index 5022dfe388ad..136acabbfab5 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -231,7 +231,7 @@ static void pagevec_move_tail_fn(struct page *page, struct lruvec *lruvec)
if (!PageUnevictable(page)) {
del_page_from_lru_list(page, lruvec, page_lru(page));
ClearPageActive(page);
- add_page_to_lru_list_tail(page, lruvec, page_lru(page));
+ add_page_to_lru_list_tail(page, lruvec);
__count_vm_events(PGROTATED, thp_nr_pages(page));
}
}
@@ -313,8 +313,7 @@ static void __activate_page(struct page *page, struct lruvec *lruvec)

del_page_from_lru_list(page, lruvec, lru);
SetPageActive(page);
- lru += LRU_ACTIVE;
- add_page_to_lru_list(page, lruvec, lru);
+ add_page_to_lru_list(page, lruvec);
trace_mm_lru_activate(page);

__count_vm_events(PGACTIVATE, nr_pages);
@@ -543,14 +542,14 @@ static void lru_deactivate_file_fn(struct page *page, struct lruvec *lruvec)
* It can make readahead confusing. But race window
* is _really_ small and it's non-critical problem.
*/
- add_page_to_lru_list(page, lruvec, lru);
+ add_page_to_lru_list(page, lruvec);
SetPageReclaim(page);
} else {
/*
* The page's writeback ends up during pagevec
* We moves tha page into tail of inactive.
*/
- add_page_to_lru_list_tail(page, lruvec, lru);
+ add_page_to_lru_list_tail(page, lruvec);
__count_vm_events(PGROTATED, nr_pages);
}

@@ -570,7 +569,7 @@ static void lru_deactivate_fn(struct page *page, struct lruvec *lruvec)
del_page_from_lru_list(page, lruvec, lru + LRU_ACTIVE);
ClearPageActive(page);
ClearPageReferenced(page);
- add_page_to_lru_list(page, lruvec, lru);
+ add_page_to_lru_list(page, lruvec);

__count_vm_events(PGDEACTIVATE, nr_pages);
__count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE,
@@ -595,7 +594,7 @@ static void lru_lazyfree_fn(struct page *page, struct lruvec *lruvec)
* anonymous pages
*/
ClearPageSwapBacked(page);
- add_page_to_lru_list(page, lruvec, LRU_INACTIVE_FILE);
+ add_page_to_lru_list(page, lruvec);

__count_vm_events(PGLAZYFREE, nr_pages);
__count_memcg_events(lruvec_memcg(lruvec), PGLAZYFREE,
@@ -1005,7 +1004,7 @@ static void __pagevec_lru_add_fn(struct page *page, struct lruvec *lruvec)
__count_vm_events(UNEVICTABLE_PGCULLED, nr_pages);
}

- add_page_to_lru_list(page, lruvec, lru);
+ add_page_to_lru_list(page, lruvec);
trace_mm_lru_insertion(page, lru);
}

diff --git a/mm/vmscan.c b/mm/vmscan.c
index a174594e40f8..8fc8f2c9d7ec 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1865,7 +1865,7 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
* inhibits memcg migration).
*/
VM_BUG_ON_PAGE(!lruvec_holds_page_lru_lock(page, lruvec), page);
- add_page_to_lru_list(page, lruvec, page_lru(page));
+ add_page_to_lru_list(page, lruvec);
nr_pages = thp_nr_pages(page);
nr_moved += nr_pages;
if (PageActive(page))
@@ -4280,12 +4280,10 @@ void check_move_unevictable_pages(struct pagevec *pvec)

lruvec = relock_page_lruvec_irq(page, lruvec);
if (page_evictable(page) && PageUnevictable(page)) {
- enum lru_list lru = page_lru_base_type(page);
-
VM_BUG_ON_PAGE(PageActive(page), page);
ClearPageUnevictable(page);
del_page_from_lru_list(page, lruvec, LRU_UNEVICTABLE);
- add_page_to_lru_list(page, lruvec, lru);
+ add_page_to_lru_list(page, lruvec);
pgrescued += nr_pages;
}
SetPageLRU(page);
--
2.29.2.576.ga3fc446d84-goog