vmscan: Use an indexed array for LRU variables
Currently we are defining explicit variables for the inactive and active
list. An indexed array can be more generic and avoid repeating similar
code in several places in the reclaim code.
We are saving a few bytes in terms of code size:
Before:
text data bss dec hex filename
4097753 573120 4092484 8763357 85b7dd vmlinux
After:
text data bss dec hex filename
4097729 573120 4092484 8763333 85b7c5 vmlinux
Having an easy way to add new lru lists may ease future work on the
reclaim code.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Christoph Lameter <cl@linux-foundation.org>
Signed-off-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/mm/vmscan.c b/mm/vmscan.c
index 1fd4912..46fdaa5 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -819,10 +819,10 @@
int active)
{
if (active)
- return isolate_lru_pages(nr, &z->active_list, dst,
+ return isolate_lru_pages(nr, &z->lru[LRU_ACTIVE].list, dst,
scanned, order, mode);
else
- return isolate_lru_pages(nr, &z->inactive_list, dst,
+ return isolate_lru_pages(nr, &z->lru[LRU_INACTIVE].list, dst,
scanned, order, mode);
}
@@ -973,10 +973,7 @@
VM_BUG_ON(PageLRU(page));
SetPageLRU(page);
list_del(&page->lru);
- if (PageActive(page))
- add_page_to_active_list(zone, page);
- else
- add_page_to_inactive_list(zone, page);
+ add_page_to_lru_list(zone, page, page_lru(page));
if (!pagevec_add(&pvec, page)) {
spin_unlock_irq(&zone->lru_lock);
__pagevec_release(&pvec);
@@ -1144,8 +1141,8 @@
int pgdeactivate = 0;
unsigned long pgscanned;
LIST_HEAD(l_hold); /* The pages which were snipped off */
- LIST_HEAD(l_inactive); /* Pages to go onto the inactive_list */
- LIST_HEAD(l_active); /* Pages to go onto the active_list */
+ LIST_HEAD(l_active);
+ LIST_HEAD(l_inactive);
struct page *page;
struct pagevec pvec;
int reclaim_mapped = 0;
@@ -1194,7 +1191,7 @@
VM_BUG_ON(!PageActive(page));
ClearPageActive(page);
- list_move(&page->lru, &zone->inactive_list);
+ list_move(&page->lru, &zone->lru[LRU_INACTIVE].list);
mem_cgroup_move_lists(page, false);
pgmoved++;
if (!pagevec_add(&pvec, page)) {
@@ -1224,7 +1221,7 @@
SetPageLRU(page);
VM_BUG_ON(!PageActive(page));
- list_move(&page->lru, &zone->active_list);
+ list_move(&page->lru, &zone->lru[LRU_ACTIVE].list);
mem_cgroup_move_lists(page, true);
pgmoved++;
if (!pagevec_add(&pvec, page)) {
@@ -1244,65 +1241,64 @@
pagevec_release(&pvec);
}
+static unsigned long shrink_list(enum lru_list l, unsigned long nr_to_scan,
+ struct zone *zone, struct scan_control *sc, int priority)
+{
+ if (l == LRU_ACTIVE) {
+ shrink_active_list(nr_to_scan, zone, sc, priority);
+ return 0;
+ }
+ return shrink_inactive_list(nr_to_scan, zone, sc);
+}
+
/*
* This is a basic per-zone page freer. Used by both kswapd and direct reclaim.
*/
static unsigned long shrink_zone(int priority, struct zone *zone,
struct scan_control *sc)
{
- unsigned long nr_active;
- unsigned long nr_inactive;
+ unsigned long nr[NR_LRU_LISTS];
unsigned long nr_to_scan;
unsigned long nr_reclaimed = 0;
+ enum lru_list l;
if (scan_global_lru(sc)) {
/*
* Add one to nr_to_scan just to make sure that the kernel
* will slowly sift through the active list.
*/
- zone->nr_scan_active +=
- (zone_page_state(zone, NR_ACTIVE) >> priority) + 1;
- nr_active = zone->nr_scan_active;
- zone->nr_scan_inactive +=
- (zone_page_state(zone, NR_INACTIVE) >> priority) + 1;
- nr_inactive = zone->nr_scan_inactive;
- if (nr_inactive >= sc->swap_cluster_max)
- zone->nr_scan_inactive = 0;
- else
- nr_inactive = 0;
-
- if (nr_active >= sc->swap_cluster_max)
- zone->nr_scan_active = 0;
- else
- nr_active = 0;
+ for_each_lru(l) {
+ zone->lru[l].nr_scan += (zone_page_state(zone,
+ NR_LRU_BASE + l) >> priority) + 1;
+ nr[l] = zone->lru[l].nr_scan;
+ if (nr[l] >= sc->swap_cluster_max)
+ zone->lru[l].nr_scan = 0;
+ else
+ nr[l] = 0;
+ }
} else {
/*
* This reclaim occurs not because zone memory shortage but
* because memory controller hits its limit.
* Then, don't modify zone reclaim related data.
*/
- nr_active = mem_cgroup_calc_reclaim_active(sc->mem_cgroup,
- zone, priority);
+ nr[LRU_ACTIVE] = mem_cgroup_calc_reclaim(sc->mem_cgroup,
+ zone, priority, LRU_ACTIVE);
- nr_inactive = mem_cgroup_calc_reclaim_inactive(sc->mem_cgroup,
- zone, priority);
+ nr[LRU_INACTIVE] = mem_cgroup_calc_reclaim(sc->mem_cgroup,
+ zone, priority, LRU_INACTIVE);
}
-
- while (nr_active || nr_inactive) {
- if (nr_active) {
- nr_to_scan = min(nr_active,
+ while (nr[LRU_ACTIVE] || nr[LRU_INACTIVE]) {
+ for_each_lru(l) {
+ if (nr[l]) {
+ nr_to_scan = min(nr[l],
(unsigned long)sc->swap_cluster_max);
- nr_active -= nr_to_scan;
- shrink_active_list(nr_to_scan, zone, sc, priority);
- }
+ nr[l] -= nr_to_scan;
- if (nr_inactive) {
- nr_to_scan = min(nr_inactive,
- (unsigned long)sc->swap_cluster_max);
- nr_inactive -= nr_to_scan;
- nr_reclaimed += shrink_inactive_list(nr_to_scan, zone,
- sc);
+ nr_reclaimed += shrink_list(l, nr_to_scan,
+ zone, sc, priority);
+ }
}
}
@@ -1819,6 +1815,7 @@
{
struct zone *zone;
unsigned long nr_to_scan, ret = 0;
+ enum lru_list l;
for_each_zone(zone) {
@@ -1828,27 +1825,24 @@
if (zone_is_all_unreclaimable(zone) && prio != DEF_PRIORITY)
continue;
- /* For pass = 0 we don't shrink the active list */
- if (pass > 0) {
- zone->nr_scan_active +=
- (zone_page_state(zone, NR_ACTIVE) >> prio) + 1;
- if (zone->nr_scan_active >= nr_pages || pass > 3) {
- zone->nr_scan_active = 0;
- nr_to_scan = min(nr_pages,
- zone_page_state(zone, NR_ACTIVE));
- shrink_active_list(nr_to_scan, zone, sc, prio);
- }
- }
+ for_each_lru(l) {
+ /* For pass = 0 we don't shrink the active list */
+ if (pass == 0 && l == LRU_ACTIVE)
+ continue;
- zone->nr_scan_inactive +=
- (zone_page_state(zone, NR_INACTIVE) >> prio) + 1;
- if (zone->nr_scan_inactive >= nr_pages || pass > 3) {
- zone->nr_scan_inactive = 0;
- nr_to_scan = min(nr_pages,
- zone_page_state(zone, NR_INACTIVE));
- ret += shrink_inactive_list(nr_to_scan, zone, sc);
- if (ret >= nr_pages)
- return ret;
+ zone->lru[l].nr_scan +=
+ (zone_page_state(zone, NR_LRU_BASE + l)
+ >> prio) + 1;
+ if (zone->lru[l].nr_scan >= nr_pages || pass > 3) {
+ zone->lru[l].nr_scan = 0;
+ nr_to_scan = min(nr_pages,
+ zone_page_state(zone,
+ NR_LRU_BASE + l));
+ ret += shrink_list(l, nr_to_scan, zone,
+ sc, prio);
+ if (ret >= nr_pages)
+ return ret;
+ }
}
}