aboutsummaryrefslogtreecommitdiffstats
path: root/mm/vmscan.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/vmscan.c')
-rw-r--r--mm/vmscan.c151
1 files changed, 97 insertions, 54 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c
index c52b23552659..49f15ef0a99a 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1138,7 +1138,7 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file)
* @mz: The mem_cgroup_zone to pull pages from.
* @dst: The temp list to put pages on to.
* @nr_scanned: The number of pages that were scanned.
- * @order: The caller's attempted allocation order
+ * @sc: The scan_control struct for this reclaim session
* @mode: One of the LRU isolation modes
* @active: True [1] if isolating active pages
* @file: True [1] if isolating file [!anon] pages
@@ -1147,8 +1147,8 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode, int file)
*/
static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
struct mem_cgroup_zone *mz, struct list_head *dst,
- unsigned long *nr_scanned, int order, isolate_mode_t mode,
- int active, int file)
+ unsigned long *nr_scanned, struct scan_control *sc,
+ isolate_mode_t mode, int active, int file)
{
struct lruvec *lruvec;
struct list_head *src;
@@ -1194,7 +1194,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
BUG();
}
- if (!order)
+ if (!sc->order || !(sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM))
continue;
/*
@@ -1208,8 +1208,8 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
*/
zone_id = page_zone_id(page);
page_pfn = page_to_pfn(page);
- pfn = page_pfn & ~((1 << order) - 1);
- end_pfn = pfn + (1 << order);
+ pfn = page_pfn & ~((1 << sc->order) - 1);
+ end_pfn = pfn + (1 << sc->order);
for (; pfn < end_pfn; pfn++) {
struct page *cursor_page;
@@ -1275,7 +1275,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
*nr_scanned = scan;
- trace_mm_vmscan_lru_isolate(order,
+ trace_mm_vmscan_lru_isolate(sc->order,
nr_to_scan, scan,
nr_taken,
nr_lumpy_taken, nr_lumpy_dirty, nr_lumpy_failed,
@@ -1413,7 +1413,6 @@ update_isolated_counts(struct mem_cgroup_zone *mz,
unsigned long *nr_anon,
unsigned long *nr_file)
{
- struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(mz);
struct zone *zone = mz->zone;
unsigned int count[NR_LRU_LISTS] = { 0, };
unsigned long nr_active = 0;
@@ -1434,6 +1433,7 @@ update_isolated_counts(struct mem_cgroup_zone *mz,
count[lru] += numpages;
}
+ preempt_disable();
__count_vm_events(PGDEACTIVATE, nr_active);
__mod_zone_page_state(zone, NR_ACTIVE_FILE,
@@ -1448,8 +1448,9 @@ update_isolated_counts(struct mem_cgroup_zone *mz,
*nr_anon = count[LRU_ACTIVE_ANON] + count[LRU_INACTIVE_ANON];
*nr_file = count[LRU_ACTIVE_FILE] + count[LRU_INACTIVE_FILE];
- reclaim_stat->recent_scanned[0] += *nr_anon;
- reclaim_stat->recent_scanned[1] += *nr_file;
+ __mod_zone_page_state(zone, NR_ISOLATED_ANON, *nr_anon);
+ __mod_zone_page_state(zone, NR_ISOLATED_FILE, *nr_file);
+ preempt_enable();
}
/*
@@ -1509,8 +1510,9 @@ shrink_inactive_list(unsigned long nr_to_scan, struct mem_cgroup_zone *mz,
unsigned long nr_file;
unsigned long nr_dirty = 0;
unsigned long nr_writeback = 0;
- isolate_mode_t reclaim_mode = ISOLATE_INACTIVE;
+ isolate_mode_t isolate_mode = ISOLATE_INACTIVE;
struct zone *zone = mz->zone;
+ struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(mz);
while (unlikely(too_many_isolated(zone, file, sc))) {
congestion_wait(BLK_RW_ASYNC, HZ/10);
@@ -1522,20 +1524,19 @@ shrink_inactive_list(unsigned long nr_to_scan, struct mem_cgroup_zone *mz,
set_reclaim_mode(priority, sc, false);
if (sc->reclaim_mode & RECLAIM_MODE_LUMPYRECLAIM)
- reclaim_mode |= ISOLATE_ACTIVE;
+ isolate_mode |= ISOLATE_ACTIVE;
lru_add_drain();
if (!sc->may_unmap)
- reclaim_mode |= ISOLATE_UNMAPPED;
+ isolate_mode |= ISOLATE_UNMAPPED;
if (!sc->may_writepage)
- reclaim_mode |= ISOLATE_CLEAN;
+ isolate_mode |= ISOLATE_CLEAN;
spin_lock_irq(&zone->lru_lock);
- nr_taken = isolate_lru_pages(nr_to_scan, mz, &page_list,
- &nr_scanned, sc->order,
- reclaim_mode, 0, file);
+ nr_taken = isolate_lru_pages(nr_to_scan, mz, &page_list, &nr_scanned,
+ sc, isolate_mode, 0, file);
if (global_reclaim(sc)) {
zone->pages_scanned += nr_scanned;
if (current_is_kswapd())
@@ -1545,19 +1546,13 @@ shrink_inactive_list(unsigned long nr_to_scan, struct mem_cgroup_zone *mz,
__count_zone_vm_events(PGSCAN_DIRECT, zone,
nr_scanned);
}
+ spin_unlock_irq(&zone->lru_lock);
- if (nr_taken == 0) {
- spin_unlock_irq(&zone->lru_lock);
+ if (nr_taken == 0)
return 0;
- }
update_isolated_counts(mz, &page_list, &nr_anon, &nr_file);
- __mod_zone_page_state(zone, NR_ISOLATED_ANON, nr_anon);
- __mod_zone_page_state(zone, NR_ISOLATED_FILE, nr_file);
-
- spin_unlock_irq(&zone->lru_lock);
-
nr_reclaimed = shrink_page_list(&page_list, mz, sc, priority,
&nr_dirty, &nr_writeback);
@@ -1570,6 +1565,9 @@ shrink_inactive_list(unsigned long nr_to_scan, struct mem_cgroup_zone *mz,
spin_lock_irq(&zone->lru_lock);
+ reclaim_stat->recent_scanned[0] += nr_anon;
+ reclaim_stat->recent_scanned[1] += nr_file;
+
if (current_is_kswapd())
__count_vm_events(KSWAPD_STEAL, nr_reclaimed);
__count_zone_vm_events(PGSTEAL, zone, nr_reclaimed);
@@ -1643,18 +1641,6 @@ static void move_active_pages_to_lru(struct zone *zone,
unsigned long pgmoved = 0;
struct page *page;
- if (buffer_heads_over_limit) {
- spin_unlock_irq(&zone->lru_lock);
- list_for_each_entry(page, list, lru) {
- if (page_has_private(page) && trylock_page(page)) {
- if (page_has_private(page))
- try_to_release_page(page, 0);
- unlock_page(page);
- }
- }
- spin_lock_irq(&zone->lru_lock);
- }
-
while (!list_empty(list)) {
struct lruvec *lruvec;
@@ -1699,21 +1685,22 @@ static void shrink_active_list(unsigned long nr_to_scan,
struct page *page;
struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(mz);
unsigned long nr_rotated = 0;
- isolate_mode_t reclaim_mode = ISOLATE_ACTIVE;
+ isolate_mode_t isolate_mode = ISOLATE_ACTIVE;
struct zone *zone = mz->zone;
lru_add_drain();
+ reset_reclaim_mode(sc);
+
if (!sc->may_unmap)
- reclaim_mode |= ISOLATE_UNMAPPED;
+ isolate_mode |= ISOLATE_UNMAPPED;
if (!sc->may_writepage)
- reclaim_mode |= ISOLATE_CLEAN;
+ isolate_mode |= ISOLATE_CLEAN;
spin_lock_irq(&zone->lru_lock);
- nr_taken = isolate_lru_pages(nr_to_scan, mz, &l_hold,
- &nr_scanned, sc->order,
- reclaim_mode, 1, file);
+ nr_taken = isolate_lru_pages(nr_to_scan, mz, &l_hold, &nr_scanned, sc,
+ isolate_mode, 1, file);
if (global_reclaim(sc))
zone->pages_scanned += nr_scanned;
@@ -1737,6 +1724,14 @@ static void shrink_active_list(unsigned long nr_to_scan,
continue;
}
+ if (unlikely(buffer_heads_over_limit)) {
+ if (page_has_private(page) && trylock_page(page)) {
+ if (page_has_private(page))
+ try_to_release_page(page, 0);
+ unlock_page(page);
+ }
+ }
+
if (page_referenced(page, 0, mz->mem_cgroup, &vm_flags)) {
nr_rotated += hpage_nr_pages(page);
/*
@@ -2112,7 +2107,12 @@ restart:
* with multiple processes reclaiming pages, the total
* freeing target can get unreasonably large.
*/
- if (nr_reclaimed >= nr_to_reclaim && priority < DEF_PRIORITY)
+ if (nr_reclaimed >= nr_to_reclaim)
+ nr_to_reclaim = 0;
+ else
+ nr_to_reclaim -= nr_reclaimed;
+
+ if (!nr_to_reclaim && priority < DEF_PRIORITY)
break;
}
blk_finish_plug(&plug);
@@ -2195,7 +2195,7 @@ static inline bool compaction_ready(struct zone *zone, struct scan_control *sc)
* If compaction is deferred, reclaim up to a point where
* compaction will have a chance of success when re-enabled
*/
- if (compaction_deferred(zone))
+ if (compaction_deferred(zone, sc->order))
return watermark_ok;
/* If compaction is not ready to start, keep reclaiming */
@@ -2235,6 +2235,14 @@ static bool shrink_zones(int priority, struct zonelist *zonelist,
unsigned long nr_soft_scanned;
bool aborted_reclaim = false;
+ /*
+ * If the number of buffer_heads in the machine exceeds the maximum
+ * allowed level, force direct reclaim to scan the highmem zone as
+ * highmem pages could be pinning lowmem pages storing buffer_heads
+ */
+ if (buffer_heads_over_limit)
+ sc->gfp_mask |= __GFP_HIGHMEM;
+
for_each_zone_zonelist_nodemask(zone, z, zonelist,
gfp_zone(sc->gfp_mask), sc->nodemask) {
if (!populated_zone(zone))
@@ -2255,8 +2263,8 @@ static bool shrink_zones(int priority, struct zonelist *zonelist,
* Even though compaction is invoked for any
* non-zero order, only frequent costly order
* reclamation is disruptive enough to become a
- * noticable problem, like transparent huge page
- * allocations.
+ * noticeable problem, like transparent huge
+ * page allocations.
*/
if (compaction_ready(zone, sc)) {
aborted_reclaim = true;
@@ -2337,7 +2345,6 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
unsigned long writeback_threshold;
bool aborted_reclaim;
- get_mems_allowed();
delayacct_freepages_start();
if (global_reclaim(sc))
@@ -2401,7 +2408,6 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
out:
delayacct_freepages_end();
- put_mems_allowed();
if (sc->nr_reclaimed)
return sc->nr_reclaimed;
@@ -2724,6 +2730,17 @@ loop_again:
*/
age_active_anon(zone, &sc, priority);
+ /*
+ * If the number of buffer_heads in the machine
+ * exceeds the maximum allowed level and this node
+ * has a highmem zone, force kswapd to reclaim from
+ * it to relieve lowmem pressure.
+ */
+ if (buffer_heads_over_limit && is_highmem_idx(i)) {
+ end_zone = i;
+ break;
+ }
+
if (!zone_watermark_ok_safe(zone, order,
high_wmark_pages(zone), 0, 0)) {
end_zone = i;
@@ -2753,7 +2770,7 @@ loop_again:
*/
for (i = 0; i <= end_zone; i++) {
struct zone *zone = pgdat->node_zones + i;
- int nr_slab;
+ int nr_slab, testorder;
unsigned long balance_gap;
if (!populated_zone(zone))
@@ -2786,7 +2803,21 @@ loop_again:
(zone->present_pages +
KSWAPD_ZONE_BALANCE_GAP_RATIO-1) /
KSWAPD_ZONE_BALANCE_GAP_RATIO);
- if (!zone_watermark_ok_safe(zone, order,
+ /*
+ * Kswapd reclaims only single pages with compaction
+ * enabled. Trying too hard to reclaim until contiguous
+ * free pages have become available can hurt performance
+ * by evicting too much useful data from memory.
+ * Do not reclaim more than needed for compaction.
+ */
+ testorder = order;
+ if (COMPACTION_BUILD && order &&
+ compaction_suitable(zone, order) !=
+ COMPACT_SKIPPED)
+ testorder = 0;
+
+ if ((buffer_heads_over_limit && is_highmem_idx(i)) ||
+ !zone_watermark_ok_safe(zone, order,
high_wmark_pages(zone) + balance_gap,
end_zone, 0)) {
shrink_zone(priority, zone, &sc);
@@ -2815,7 +2846,7 @@ loop_again:
continue;
}
- if (!zone_watermark_ok_safe(zone, order,
+ if (!zone_watermark_ok_safe(zone, testorder,
high_wmark_pages(zone), end_zone, 0)) {
all_zones_ok = 0;
/*
@@ -2903,6 +2934,8 @@ out:
* and it is potentially going to sleep here.
*/
if (order) {
+ int zones_need_compaction = 1;
+
for (i = 0; i <= end_zone; i++) {
struct zone *zone = pgdat->node_zones + i;
@@ -2912,6 +2945,10 @@ out:
if (zone->all_unreclaimable && priority != DEF_PRIORITY)
continue;
+ /* Would compaction fail due to lack of free memory? */
+ if (compaction_suitable(zone, order) == COMPACT_SKIPPED)
+ goto loop_again;
+
/* Confirm the zone is balanced for order-0 */
if (!zone_watermark_ok(zone, 0,
high_wmark_pages(zone), 0, 0)) {
@@ -2919,11 +2956,17 @@ out:
goto loop_again;
}
+ /* Check if the memory needs to be defragmented. */
+ if (zone_watermark_ok(zone, order,
+ low_wmark_pages(zone), *classzone_idx, 0))
+ zones_need_compaction = 0;
+
/* If balanced, clear the congested flag */
zone_clear_flag(zone, ZONE_CONGESTED);
- if (i <= *classzone_idx)
- balanced += zone->present_pages;
}
+
+ if (zones_need_compaction)
+ compact_pgdat(pgdat, order);
}
/*
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.