mm: introduce page_lru_base_type()
Instead of abusing page_is_file_cache() for LRU list index arithmetic, add
another helper with a more appropriate name and convert the non-boolean
users of page_is_file_cache() accordingly.
This new helper gives the LRU base type a page is supposed to live on,
inactive anon or inactive file.
[hugh.dickins@tiscali.co.uk: convert del_page_from_lru() also]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h
index 7fbb972..99977ff 100644
--- a/include/linux/mm_inline.h
+++ b/include/linux/mm_inline.h
@@ -39,21 +39,36 @@
mem_cgroup_del_lru_list(page, l);
}
+/**
+ * page_lru_base_type - which LRU list type should a page be on?
+ * @page: the page to test
+ *
+ * Used for LRU list index arithmetic.
+ *
+ * Returns the base LRU type - file or anon - @page should be on.
+ */
+static inline enum lru_list page_lru_base_type(struct page *page)
+{
+ if (page_is_file_cache(page))
+ return LRU_INACTIVE_FILE;
+ return LRU_INACTIVE_ANON;
+}
+
static inline void
del_page_from_lru(struct zone *zone, struct page *page)
{
- enum lru_list l = LRU_BASE;
+ enum lru_list l;
list_del(&page->lru);
if (PageUnevictable(page)) {
__ClearPageUnevictable(page);
l = LRU_UNEVICTABLE;
} else {
+ l = page_lru_base_type(page);
if (PageActive(page)) {
__ClearPageActive(page);
l += LRU_ACTIVE;
}
- l += page_is_file_cache(page);
}
__dec_zone_state(zone, NR_LRU_BASE + l);
mem_cgroup_del_lru_list(page, l);
@@ -68,14 +83,14 @@
*/
static inline enum lru_list page_lru(struct page *page)
{
- enum lru_list lru = LRU_BASE;
+ enum lru_list lru;
if (PageUnevictable(page))
lru = LRU_UNEVICTABLE;
else {
+ lru = page_lru_base_type(page);
if (PageActive(page))
lru += LRU_ACTIVE;
- lru += page_is_file_cache(page);
}
return lru;
diff --git a/mm/swap.c b/mm/swap.c
index cb29ae5..168d53e 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -118,7 +118,7 @@
spin_lock(&zone->lru_lock);
}
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
- int lru = page_is_file_cache(page);
+ int lru = page_lru_base_type(page);
list_move_tail(&page->lru, &zone->lru[lru].list);
pgmoved++;
}
@@ -181,7 +181,7 @@
spin_lock_irq(&zone->lru_lock);
if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) {
int file = page_is_file_cache(page);
- int lru = LRU_BASE + file;
+ int lru = page_lru_base_type(page);
del_page_from_lru_list(zone, page, lru);
SetPageActive(page);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index cad5d52..30e56ee 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -531,7 +531,7 @@
* unevictable page on [in]active list.
* We know how to handle that.
*/
- lru = active + page_is_file_cache(page);
+ lru = active + page_lru_base_type(page);
lru_cache_add_lru(page, lru);
} else {
/*
@@ -986,7 +986,7 @@
struct page *page;
list_for_each_entry(page, page_list, lru) {
- lru = page_is_file_cache(page);
+ lru = page_lru_base_type(page);
if (PageActive(page)) {
lru += LRU_ACTIVE;
ClearPageActive(page);
@@ -2652,7 +2652,7 @@
retry:
ClearPageUnevictable(page);
if (page_evictable(page, NULL)) {
- enum lru_list l = LRU_INACTIVE_ANON + page_is_file_cache(page);
+ enum lru_list l = page_lru_base_type(page);
__dec_zone_state(zone, NR_UNEVICTABLE);
list_move(&page->lru, &zone->lru[l].list);