return PAGEREF_RECLAIM;
if (referenced_ptes) {
- if (PageAnon(page))
+ if (PageSwapBacked(page))
return PAGEREF_ACTIVATE;
/*
* All mapped pages start out with page table
u64 fraction[2], denominator;
enum lru_list l;
int noswap = 0;
- int force_scan = 0;
+ bool force_scan = false;
+ unsigned long nr_force_scan[2];
-
- anon = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_ANON) +
- zone_nr_lru_pages(zone, sc, LRU_INACTIVE_ANON);
- file = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_FILE) +
- zone_nr_lru_pages(zone, sc, LRU_INACTIVE_FILE);
-
- if (((anon + file) >> priority) < SWAP_CLUSTER_MAX) {
- /* kswapd does zone balancing and need to scan this zone */
- if (scanning_global_lru(sc) && current_is_kswapd())
- force_scan = 1;
- /* memcg may have small limit and need to avoid priority drop */
- if (!scanning_global_lru(sc))
- force_scan = 1;
- }
+ /* kswapd does zone balancing and needs to scan this zone */
+ if (scanning_global_lru(sc) && current_is_kswapd())
+ force_scan = true;
+ /* memcg may have small limit and need to avoid priority drop */
+ if (!scanning_global_lru(sc))
+ force_scan = true;
/* If we have no swap space, do not bother scanning anon pages. */
if (!sc->may_swap || (nr_swap_pages <= 0)) {
fraction[0] = 0;
fraction[1] = 1;
denominator = 1;
+ nr_force_scan[0] = 0;
+ nr_force_scan[1] = SWAP_CLUSTER_MAX;
goto out;
}
+ anon = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_ANON) +
+ zone_nr_lru_pages(zone, sc, LRU_INACTIVE_ANON);
+ file = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_FILE) +
+ zone_nr_lru_pages(zone, sc, LRU_INACTIVE_FILE);
+
if (scanning_global_lru(sc)) {
free = zone_page_state(zone, NR_FREE_PAGES);
/* If we have very few page cache pages,
fraction[0] = 1;
fraction[1] = 0;
denominator = 1;
+ nr_force_scan[0] = SWAP_CLUSTER_MAX;
+ nr_force_scan[1] = 0;
goto out;
}
}
fraction[0] = ap;
fraction[1] = fp;
denominator = ap + fp + 1;
+ if (force_scan) {
+ unsigned long scan = SWAP_CLUSTER_MAX;
+ nr_force_scan[0] = div64_u64(scan * ap, denominator);
+ nr_force_scan[1] = div64_u64(scan * fp, denominator);
+ }
out:
for_each_evictable_lru(l) {
int file = is_file_lru(l);
* memcg, priority drop can cause big latency. So, it's better
* to scan small amount. See may_noscan above.
*/
- if (!scan && force_scan) {
- if (file)
- scan = SWAP_CLUSTER_MAX;
- else if (!noswap)
- scan = SWAP_CLUSTER_MAX;
- }
+ if (!scan && force_scan)
+ scan = nr_force_scan[file];
nr[l] = scan;
}
}
for (i = 0; i <= classzone_idx; i++)
present_pages += pgdat->node_zones[i].present_pages;
- return balanced_pages > (present_pages >> 2);
+ /* A special case here: if zone has no page, we think it's balanced */
+ return balanced_pages >= (present_pages >> 2);
}
/* is kswapd sleeping prematurely? */
high_wmark_pages(zone), 0, 0)) {
end_zone = i;
break;
+ } else {
+ /* If balanced, clear the congested flag */
+ zone_clear_flag(zone, ZONE_CONGESTED);
}
}
if (i < 0)
* them before going back to sleep.
*/
set_pgdat_percpu_threshold(pgdat, calculate_normal_threshold);
- schedule();
+
+ if (!kthread_should_stop())
+ schedule();
+
set_pgdat_percpu_threshold(pgdat, calculate_pressure_threshold);
} else {
if (remaining)
}
/*
- * Called by memory hotplug when all memory in a node is offlined.
+ * Called by memory hotplug when all memory in a node is offlined. Caller must
+ * hold lock_memory_hotplug().
*/
void kswapd_stop(int nid)
{
struct task_struct *kswapd = NODE_DATA(nid)->kswapd;
- if (kswapd)
+ if (kswapd) {
kthread_stop(kswapd);
+ NODE_DATA(nid)->kswapd = NULL;
+ }
}
static int __init kswapd_init(void)