From 06e6006a04f7307369441554eb330199e5e8d262 Mon Sep 17 00:00:00 2001 From: Kalesh Singh Date: Tue, 8 Nov 2022 09:09:16 -0800 Subject: [PATCH] Revert "FROMLIST: mm: multi-gen LRU: thrashing prevention" This reverts commit 96f4a592d31ad805c3114c7c2f0d3f117a09d14f. To be replaced with upstream version. Bug: 249601646 Change-Id: I65c85dfac185be27bb14a8be7324c5cc985df9c8 Signed-off-by: Kalesh Singh --- include/linux/mmzone.h | 2 -- mm/vmscan.c | 69 +++--------------------------------------- 2 files changed, 4 insertions(+), 67 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 5f982dcdbc37..5a1d98745c59 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -380,8 +380,6 @@ struct lru_gen_struct { unsigned long max_seq; /* the eviction increments the oldest generation numbers */ unsigned long min_seq[ANON_AND_FILE]; - /* the birth time of each generation in jiffies */ - unsigned long timestamps[MAX_NR_GENS]; /* the multi-gen LRU lists */ struct list_head lists[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; /* the sizes of the above lists */ diff --git a/mm/vmscan.c b/mm/vmscan.c index ed15e01c8b7f..ba8b1c5de9eb 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3826,7 +3826,6 @@ static void inc_max_seq(struct lruvec *lruvec) for (type = 0; type < ANON_AND_FILE; type++) reset_ctrl_pos(lruvec, type, false); - WRITE_ONCE(lrugen->timestamps[next], jiffies); /* make sure preceding modifications appear */ smp_store_release(&lrugen->max_seq, lrugen->max_seq + 1); @@ -3952,8 +3951,7 @@ static long get_nr_evictable(struct lruvec *lruvec, unsigned long max_seq, return total > 0 ? total : 0; } -static bool age_lruvec(struct lruvec *lruvec, struct scan_control *sc, - unsigned long min_ttl) +static void age_lruvec(struct lruvec *lruvec, struct scan_control *sc) { bool need_aging; long nr_to_scan; @@ -3962,22 +3960,14 @@ static bool age_lruvec(struct lruvec *lruvec, struct scan_control *sc, DEFINE_MAX_SEQ(lruvec); DEFINE_MIN_SEQ(lruvec); - if (min_ttl) { - int gen = lru_gen_from_seq(min_seq[LRU_GEN_FILE]); - unsigned long birth = READ_ONCE(lruvec->lrugen.timestamps[gen]); - - if (time_is_after_jiffies(birth + min_ttl)) - return false; - } - mem_cgroup_calculate_protection(NULL, memcg); if (mem_cgroup_below_min(memcg)) - return false; + return; nr_to_scan = get_nr_evictable(lruvec, max_seq, min_seq, swappiness, &need_aging); if (!nr_to_scan) - return false; + return; nr_to_scan >>= sc->priority; @@ -3986,18 +3976,11 @@ static bool age_lruvec(struct lruvec *lruvec, struct scan_control *sc, if (nr_to_scan && need_aging && (!mem_cgroup_below_low(memcg) || sc->memcg_low_reclaim)) try_to_inc_max_seq(lruvec, max_seq, sc, swappiness, false); - - return true; } -/* to protect the working set of the last N jiffies */ -static unsigned long lru_gen_min_ttl __read_mostly; - static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) { struct mem_cgroup *memcg; - bool success = false; - unsigned long min_ttl = READ_ONCE(lru_gen_min_ttl); VM_BUG_ON(!current_is_kswapd()); @@ -4023,29 +4006,12 @@ static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) do { struct lruvec *lruvec = mem_cgroup_lruvec(memcg, pgdat); - if (age_lruvec(lruvec, sc, min_ttl)) - success = true; + age_lruvec(lruvec, sc); cond_resched(); } while ((memcg = mem_cgroup_iter(NULL, memcg, NULL))); current->reclaim_state->mm_walk = NULL; - - /* - * The main goal is to OOM kill if every generation from all memcgs is - * younger than min_ttl. However, another theoretical possibility is all - * memcgs are either below min or empty. - */ - if (!success && mutex_trylock(&oom_lock)) { - struct oom_control oc = { - .gfp_mask = sc->gfp_mask, - .order = sc->order, - }; - - out_of_memory(&oc); - - mutex_unlock(&oom_lock); - } } /* @@ -4767,28 +4733,6 @@ unlock: * sysfs interface ******************************************************************************/ -static ssize_t show_min_ttl(struct kobject *kobj, struct kobj_attribute *attr, char *buf) -{ - return sprintf(buf, "%u\n", jiffies_to_msecs(READ_ONCE(lru_gen_min_ttl))); -} - -static ssize_t store_min_ttl(struct kobject *kobj, struct kobj_attribute *attr, - const char *buf, size_t len) -{ - unsigned int msecs; - - if (kstrtouint(buf, 0, &msecs)) - return -EINVAL; - - WRITE_ONCE(lru_gen_min_ttl, msecs_to_jiffies(msecs)); - - return len; -} - -static struct kobj_attribute lru_gen_min_ttl_attr = __ATTR( - min_ttl_ms, 0644, show_min_ttl, store_min_ttl -); - static ssize_t show_enable(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { unsigned int caps = 0; @@ -4837,7 +4781,6 @@ static struct kobj_attribute lru_gen_enabled_attr = __ATTR( ); static struct attribute *lru_gen_attrs[] = { - &lru_gen_min_ttl_attr.attr, &lru_gen_enabled_attr.attr, NULL }; @@ -4853,16 +4796,12 @@ static struct attribute_group lru_gen_attr_group = { void lru_gen_init_lruvec(struct lruvec *lruvec) { - int i; int gen, type, zone; struct lru_gen_struct *lrugen = &lruvec->lrugen; lrugen->max_seq = MIN_NR_GENS + 1; lrugen->enabled = lru_gen_enabled(); - for (i = 0; i <= MIN_NR_GENS + 1; i++) - lrugen->timestamps[i] = jiffies; - for_each_gen_type_zone(gen, type, zone) INIT_LIST_HEAD(&lrugen->lists[gen][type][zone]);