#define SHRINK_BATCH 128
-static unsigned long
-shrink_slab_node(struct shrink_control *shrinkctl, struct shrinker *shrinker,
- unsigned long nr_pages_scanned, unsigned long lru_pages)
+static unsigned long shrink_slabs(struct shrink_control *shrinkctl,
+ struct shrinker *shrinker,
+ unsigned long nr_scanned,
+ unsigned long nr_eligible)
{
unsigned long freed = 0;
unsigned long long delta;
nr = atomic_long_xchg(&shrinker->nr_deferred[nid], 0);
total_scan = nr;
- delta = (4 * nr_pages_scanned) / shrinker->seeks;
+ delta = (4 * nr_scanned) / shrinker->seeks;
delta *= freeable;
- do_div(delta, lru_pages + 1);
+ do_div(delta, nr_eligible + 1);
total_scan += delta;
if (total_scan < 0) {
pr_err("shrink_slab: %pF negative objects to delete nr=%ld\n",
total_scan = freeable * 2;
trace_mm_shrink_slab_start(shrinker, shrinkctl, nr,
- nr_pages_scanned, lru_pages,
- freeable, delta, total_scan);
+ nr_scanned, nr_eligible,
+ freeable, delta, total_scan);
/*
* Normally, we should not scan less than batch_size objects in one
return freed;
}
-/*
- * Call the shrink functions to age shrinkable caches
- *
- * Here we assume it costs one seek to replace a lru page and that it also
- * takes a seek to recreate a cache object. With this in mind we age equal
- * percentages of the lru and ageable caches. This should balance the seeks
- * generated by these structures.
+/**
+ * shrink_node_slabs - shrink slab caches of a given node
+ * @gfp_mask: allocation context
+ * @nid: node whose slab caches to target
+ * @nr_scanned: pressure numerator
+ * @nr_eligible: pressure denominator
*
- * If the vm encountered mapped pages on the LRU it increase the pressure on
- * slab to avoid swapping.
+ * Call the shrink functions to age shrinkable caches.
*
- * We do weird things to avoid (scanned*seeks*entries) overflowing 32 bits.
+ * @nid is passed along to shrinkers with SHRINKER_NUMA_AWARE set,
+ * unaware shrinkers will receive a node id of 0 instead.
*
- * `lru_pages' represents the number of on-LRU pages in all the zones which
- * are eligible for the caller's allocation attempt. It is used for balancing
- * slab reclaim versus page reclaim.
+ * @nr_scanned and @nr_eligible form a ratio that indicate how much of
+ * the available objects should be scanned. Page reclaim for example
+ * passes the number of pages scanned and the number of pages on the
+ * LRU lists that it considered on @nid, plus a bias in @nr_scanned
+ * when it encountered mapped pages. The ratio is further biased by
+ * the ->seeks setting of the shrink function, which indicates the
+ * cost to recreate an object relative to that of an LRU page.
*
- * Returns the number of slab objects which we shrunk.
+ * Returns the number of reclaimed slab objects.
*/
-unsigned long shrink_slab(struct shrink_control *shrinkctl,
- unsigned long nr_pages_scanned,
- unsigned long lru_pages)
+unsigned long shrink_node_slabs(gfp_t gfp_mask, int nid,
+ unsigned long nr_scanned,
+ unsigned long nr_eligible)
{
struct shrinker *shrinker;
unsigned long freed = 0;
- if (nr_pages_scanned == 0)
- nr_pages_scanned = SWAP_CLUSTER_MAX;
+ if (nr_scanned == 0)
+ nr_scanned = SWAP_CLUSTER_MAX;
if (!down_read_trylock(&shrinker_rwsem)) {
/*
}
list_for_each_entry(shrinker, &shrinker_list, list) {
- if (!(shrinker->flags & SHRINKER_NUMA_AWARE)) {
- shrinkctl->nid = 0;
- freed += shrink_slab_node(shrinkctl, shrinker,
- nr_pages_scanned, lru_pages);
- continue;
- }
+ struct shrink_control sc = {
+ .gfp_mask = gfp_mask,
+ .nid = nid,
+ };
- for_each_node_mask(shrinkctl->nid, shrinkctl->nodes_to_scan) {
- if (node_online(shrinkctl->nid))
- freed += shrink_slab_node(shrinkctl, shrinker,
- nr_pages_scanned, lru_pages);
+ if (!(shrinker->flags & SHRINKER_NUMA_AWARE))
+ sc.nid = 0;
- }
+ freed += shrink_slabs(&sc, shrinker, nr_scanned, nr_eligible);
}
+
up_read(&shrinker_rwsem);
out:
cond_resched();
* nr[2] = file inactive pages to scan; nr[3] = file active pages to scan
*/
static void get_scan_count(struct lruvec *lruvec, int swappiness,
- struct scan_control *sc, unsigned long *nr)
+ struct scan_control *sc, unsigned long *nr,
+ unsigned long *lru_pages)
{
struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat;
u64 fraction[2];
some_scanned = false;
/* Only use force_scan on second pass. */
for (pass = 0; !some_scanned && pass < 2; pass++) {
+ *lru_pages = 0;
for_each_evictable_lru(lru) {
int file = is_file_lru(lru);
unsigned long size;
case SCAN_FILE:
case SCAN_ANON:
/* Scan one type exclusively */
- if ((scan_balance == SCAN_FILE) != file)
+ if ((scan_balance == SCAN_FILE) != file) {
+ size = 0;
scan = 0;
+ }
break;
default:
/* Look ma, no brain */
BUG();
}
+
+ *lru_pages += size;
nr[lru] = scan;
+
/*
* Skip the second pass and don't force_scan,
* if we found something to scan.
* This is a basic per-zone page freer. Used by both kswapd and direct reclaim.
*/
static void shrink_lruvec(struct lruvec *lruvec, int swappiness,
- struct scan_control *sc)
+ struct scan_control *sc, unsigned long *lru_pages)
{
unsigned long nr[NR_LRU_LISTS];
unsigned long targets[NR_LRU_LISTS];
struct blk_plug plug;
bool scan_adjusted;
- get_scan_count(lruvec, swappiness, sc, nr);
+ get_scan_count(lruvec, swappiness, sc, nr, lru_pages);
/* Record the original scan target for proportional adjustments later */
memcpy(targets, nr, sizeof(nr));
}
}
-static bool shrink_zone(struct zone *zone, struct scan_control *sc)
+static bool shrink_zone(struct zone *zone, struct scan_control *sc,
+ bool is_classzone)
{
unsigned long nr_reclaimed, nr_scanned;
bool reclaimable = false;
.zone = zone,
.priority = sc->priority,
};
+ unsigned long zone_lru_pages = 0;
struct mem_cgroup *memcg;
nr_reclaimed = sc->nr_reclaimed;
memcg = mem_cgroup_iter(root, NULL, &reclaim);
do {
+ unsigned long lru_pages;
struct lruvec *lruvec;
int swappiness;
lruvec = mem_cgroup_zone_lruvec(zone, memcg);
swappiness = mem_cgroup_swappiness(memcg);
- shrink_lruvec(lruvec, swappiness, sc);
+ shrink_lruvec(lruvec, swappiness, sc, &lru_pages);
+ zone_lru_pages += lru_pages;
/*
* Direct reclaim and kswapd have to scan all memory
memcg = mem_cgroup_iter(root, memcg, &reclaim);
} while (memcg);
+ /*
+ * Shrink the slab caches in the same proportion that
+ * the eligible LRU pages were scanned.
+ */
+ if (global_reclaim(sc) && is_classzone) {
+ struct reclaim_state *reclaim_state;
+
+ shrink_node_slabs(sc->gfp_mask, zone_to_nid(zone),
+ sc->nr_scanned - nr_scanned,
+ zone_lru_pages);
+
+ reclaim_state = current->reclaim_state;
+ if (reclaim_state) {
+ sc->nr_reclaimed +=
+ reclaim_state->reclaimed_slab;
+ reclaim_state->reclaimed_slab = 0;
+ }
+ }
+
vmpressure(sc->gfp_mask, sc->target_mem_cgroup,
sc->nr_scanned - nr_scanned,
sc->nr_reclaimed - nr_reclaimed);
struct zone *zone;
unsigned long nr_soft_reclaimed;
unsigned long nr_soft_scanned;
- unsigned long lru_pages = 0;
- struct reclaim_state *reclaim_state = current->reclaim_state;
gfp_t orig_mask;
- struct shrink_control shrink = {
- .gfp_mask = sc->gfp_mask,
- };
enum zone_type requested_highidx = gfp_zone(sc->gfp_mask);
bool reclaimable = false;
if (buffer_heads_over_limit)
sc->gfp_mask |= __GFP_HIGHMEM;
- nodes_clear(shrink.nodes_to_scan);
-
for_each_zone_zonelist_nodemask(zone, z, zonelist,
- gfp_zone(sc->gfp_mask), sc->nodemask) {
+ requested_highidx, sc->nodemask) {
+ enum zone_type classzone_idx;
+
if (!populated_zone(zone))
continue;
+
+ classzone_idx = requested_highidx;
+ while (!populated_zone(zone->zone_pgdat->node_zones +
+ classzone_idx))
+ classzone_idx--;
+
/*
* Take care memory controller reclaiming has small influence
* to global LRU.
GFP_KERNEL | __GFP_HARDWALL))
continue;
- lru_pages += zone_reclaimable_pages(zone);
- node_set(zone_to_nid(zone), shrink.nodes_to_scan);
-
if (sc->priority != DEF_PRIORITY &&
!zone_reclaimable(zone))
continue; /* Let kswapd poll it */
/* need some check for avoid more shrink_zone() */
}
- if (shrink_zone(zone, sc))
+ if (shrink_zone(zone, sc, zone_idx(zone) == classzone_idx))
reclaimable = true;
if (global_reclaim(sc) &&
reclaimable = true;
}
- /*
- * Don't shrink slabs when reclaiming memory from over limit cgroups
- * but do shrink slab at least once when aborting reclaim for
- * compaction to avoid unevenly scanning file/anon LRU pages over slab
- * pages.
- */
- if (global_reclaim(sc)) {
- shrink_slab(&shrink, sc->nr_scanned, lru_pages);
- if (reclaim_state) {
- sc->nr_reclaimed += reclaim_state->reclaimed_slab;
- reclaim_state->reclaimed_slab = 0;
- }
- }
-
/*
* Restore to original mask to avoid the impact on the caller if we
* promoted it to __GFP_HIGHMEM.
};
struct lruvec *lruvec = mem_cgroup_zone_lruvec(zone, memcg);
int swappiness = mem_cgroup_swappiness(memcg);
+ unsigned long lru_pages;
sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
(GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK);
* will pick up pages from other mem cgroup's as well. We hack
* the priority and make it zero.
*/
- shrink_lruvec(lruvec, swappiness, &sc);
+ shrink_lruvec(lruvec, swappiness, &sc, &lru_pages);
trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed);
static bool kswapd_shrink_zone(struct zone *zone,
int classzone_idx,
struct scan_control *sc,
- unsigned long lru_pages,
unsigned long *nr_attempted)
{
int testorder = sc->order;
unsigned long balance_gap;
- struct reclaim_state *reclaim_state = current->reclaim_state;
- struct shrink_control shrink = {
- .gfp_mask = sc->gfp_mask,
- };
bool lowmem_pressure;
/* Reclaim above the high watermark. */
balance_gap, classzone_idx))
return true;
- shrink_zone(zone, sc);
- nodes_clear(shrink.nodes_to_scan);
- node_set(zone_to_nid(zone), shrink.nodes_to_scan);
-
- reclaim_state->reclaimed_slab = 0;
- shrink_slab(&shrink, sc->nr_scanned, lru_pages);
- sc->nr_reclaimed += reclaim_state->reclaimed_slab;
+ shrink_zone(zone, sc, zone_idx(zone) == classzone_idx);
/* Account for the number of pages attempted to reclaim */
*nr_attempted += sc->nr_to_reclaim;
count_vm_event(PAGEOUTRUN);
do {
- unsigned long lru_pages = 0;
unsigned long nr_attempted = 0;
bool raise_priority = true;
bool pgdat_needs_compaction = (order > 0);
if (!populated_zone(zone))
continue;
- lru_pages += zone_reclaimable_pages(zone);
-
/*
* If any zone is currently balanced then kswapd will
* not call compaction as it is expected that the
* that that high watermark would be met at 100%
* efficiency.
*/
- if (kswapd_shrink_zone(zone, end_zone, &sc,
- lru_pages, &nr_attempted))
+ if (kswapd_shrink_zone(zone, end_zone,
+ &sc, &nr_attempted))
raise_priority = false;
}
.may_unmap = !!(zone_reclaim_mode & RECLAIM_SWAP),
.may_swap = 1,
};
- struct shrink_control shrink = {
- .gfp_mask = sc.gfp_mask,
- };
- unsigned long nr_slab_pages0, nr_slab_pages1;
cond_resched();
/*
* priorities until we have enough memory freed.
*/
do {
- shrink_zone(zone, &sc);
+ shrink_zone(zone, &sc, true);
} while (sc.nr_reclaimed < nr_pages && --sc.priority >= 0);
}
- nr_slab_pages0 = zone_page_state(zone, NR_SLAB_RECLAIMABLE);
- if (nr_slab_pages0 > zone->min_slab_pages) {
- /*
- * shrink_slab() does not currently allow us to determine how
- * many pages were freed in this zone. So we take the current
- * number of slab pages and shake the slab until it is reduced
- * by the same nr_pages that we used for reclaiming unmapped
- * pages.
- */
- nodes_clear(shrink.nodes_to_scan);
- node_set(zone_to_nid(zone), shrink.nodes_to_scan);
- for (;;) {
- unsigned long lru_pages = zone_reclaimable_pages(zone);
-
- /* No reclaimable slab or very low memory pressure */
- if (!shrink_slab(&shrink, sc.nr_scanned, lru_pages))
- break;
-
- /* Freed enough memory */
- nr_slab_pages1 = zone_page_state(zone,
- NR_SLAB_RECLAIMABLE);
- if (nr_slab_pages1 + nr_pages <= nr_slab_pages0)
- break;
- }
-
- /*
- * Update nr_reclaimed by the number of slab pages we
- * reclaimed from this zone.
- */
- nr_slab_pages1 = zone_page_state(zone, NR_SLAB_RECLAIMABLE);
- if (nr_slab_pages1 < nr_slab_pages0)
- sc.nr_reclaimed += nr_slab_pages0 - nr_slab_pages1;
- }
-
p->reclaim_state = NULL;
current->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE);
lockdep_clear_current_reclaim_state();
projects / deliverable / linux.git / commitdiff
