1 files changed, 36 insertions, 39 deletions

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 809025ed97ea..f5fa1bd1eb16 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -954,7 +954,6 @@ const char * const vmstat_text[] = {
         "nr_unevictable",
         "nr_isolated_anon",
         "nr_isolated_file",
-        "nr_pages_scanned",
         "workingset_refault",
         "workingset_activate",
         "workingset_nodereclaim",
@@ -992,6 +991,7 @@ const char * const vmstat_text[] = {
         "pgfree",
         "pgactivate",
         "pgdeactivate",
+        "pglazyfree",
 
         "pgfault",
         "pgmajfault",
@@ -1124,8 +1124,12 @@ static void frag_stop(struct seq_file *m, void *arg)
 {
 }
 
-/* Walk all the zones in a node and print using a callback */
+/*
+ * Walk zones in a node and print using a callback.
+ * If @assert_populated is true, only use callback for zones that are populated.
+ */
 static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
+                bool assert_populated,
                 void (*print)(struct seq_file *m, pg_data_t *, struct zone *))
 {
         struct zone *zone;
@@ -1133,7 +1137,7 @@ static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
         unsigned long flags;
 
         for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
-                if (!populated_zone(zone))
+                if (assert_populated && !populated_zone(zone))
                         continue;
 
                 spin_lock_irqsave(&zone->lock, flags);
@@ -1161,7 +1165,7 @@ static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
 static int frag_show(struct seq_file *m, void *arg)
 {
         pg_data_t *pgdat = (pg_data_t *)arg;
-        walk_zones_in_node(m, pgdat, frag_show_print);
+        walk_zones_in_node(m, pgdat, true, frag_show_print);
         return 0;
 }
 
@@ -1202,7 +1206,7 @@ static int pagetypeinfo_showfree(struct seq_file *m, void *arg)
                 seq_printf(m, "%6d ", order);
         seq_putc(m, '\n');
 
-        walk_zones_in_node(m, pgdat, pagetypeinfo_showfree_print);
+        walk_zones_in_node(m, pgdat, true, pagetypeinfo_showfree_print);
 
         return 0;
 }
@@ -1254,7 +1258,7 @@ static int pagetypeinfo_showblockcount(struct seq_file *m, void *arg)
         for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
                 seq_printf(m, "%12s ", migratetype_names[mtype]);
         seq_putc(m, '\n');
-        walk_zones_in_node(m, pgdat, pagetypeinfo_showblockcount_print);
+        walk_zones_in_node(m, pgdat, true, pagetypeinfo_showblockcount_print);
 
         return 0;
 }
@@ -1280,7 +1284,7 @@ static void pagetypeinfo_showmixedcount(struct seq_file *m, pg_data_t *pgdat)
                 seq_printf(m, "%12s ", migratetype_names[mtype]);
         seq_putc(m, '\n');
 
-        walk_zones_in_node(m, pgdat, pagetypeinfo_showmixedcount_print);
+        walk_zones_in_node(m, pgdat, true, pagetypeinfo_showmixedcount_print);
 #endif /* CONFIG_PAGE_OWNER */
 }
 
@@ -1378,7 +1382,6 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
                    "\n        min      %lu"
                    "\n        low      %lu"
                    "\n        high     %lu"
-                   "\n   node_scanned  %lu"
                    "\n        spanned  %lu"
                    "\n        present  %lu"
                    "\n        managed  %lu",
@@ -1386,23 +1389,28 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
                    min_wmark_pages(zone),
                    low_wmark_pages(zone),
                    high_wmark_pages(zone),
-                   node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED),
                    zone->spanned_pages,
                    zone->present_pages,
                    zone->managed_pages);
 
-        for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
-                seq_printf(m, "\n      %-12s %lu", vmstat_text[i],
-                                zone_page_state(zone, i));
-
         seq_printf(m,
                    "\n        protection: (%ld",
                    zone->lowmem_reserve[0]);
         for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
                 seq_printf(m, ", %ld", zone->lowmem_reserve[i]);
-        seq_printf(m,
-                   ")"
-                   "\n  pagesets");
+        seq_putc(m, ')');
+
+        /* If unpopulated, no other information is useful */
+        if (!populated_zone(zone)) {
+                seq_putc(m, '\n');
+                return;
+        }
+
+        for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
+                seq_printf(m, "\n      %-12s %lu", vmstat_text[i],
+                                zone_page_state(zone, i));
+
+        seq_printf(m, "\n  pagesets");
         for_each_online_cpu(i) {
                 struct per_cpu_pageset *pageset;
 
@@ -1425,19 +1433,22 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
                    "\n  node_unreclaimable:  %u"
                    "\n  start_pfn:           %lu"
                    "\n  node_inactive_ratio: %u",
-                   !pgdat_reclaimable(zone->zone_pgdat),
+                   pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES,
                    zone->zone_start_pfn,
                    zone->zone_pgdat->inactive_ratio);
         seq_putc(m, '\n');
 }
 
 /*
- * Output information about zones in @pgdat.
+ * Output information about zones in @pgdat.  All zones are printed regardless
+ * of whether they are populated or not: lowmem_reserve_ratio operates on the
+ * set of all zones and userspace would not be aware of such zones if they are
+ * suppressed here (zoneinfo displays the effect of lowmem_reserve_ratio).
  */
 static int zoneinfo_show(struct seq_file *m, void *arg)
 {
         pg_data_t *pgdat = (pg_data_t *)arg;
-        walk_zones_in_node(m, pgdat, zoneinfo_show_print);
+        walk_zones_in_node(m, pgdat, false, zoneinfo_show_print);
         return 0;
 }
 
@@ -1586,22 +1597,9 @@ int vmstat_refresh(struct ctl_table *table, int write,
         for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
                 val = atomic_long_read(&vm_zone_stat[i]);
                 if (val < 0) {
-                        switch (i) {
-                        case NR_PAGES_SCANNED:
-                                /*
-                                 * This is often seen to go negative in
-                                 * recent kernels, but not to go permanently
-                                 * negative.  Whilst it would be nicer not to
-                                 * have exceptions, rooting them out would be
-                                 * another task, of rather low priority.
-                                 */
-                                break;
-                        default:
-                                pr_warn("%s: %s %ld\n",
-                                        __func__, vmstat_text[i], val);
-                                err = -EINVAL;
-                                break;
-                        }
+                        pr_warn("%s: %s %ld\n",
+                                __func__, vmstat_text[i], val);
+                        err = -EINVAL;
                 }
         }
         if (err)
@@ -1768,8 +1766,7 @@ void __init init_mm_internals(void)
 {
         int ret __maybe_unused;
 
-        mm_percpu_wq = alloc_workqueue("mm_percpu_wq",
-                                       WQ_FREEZABLE|WQ_MEM_RECLAIM, 0);
+        mm_percpu_wq = alloc_workqueue("mm_percpu_wq", WQ_MEM_RECLAIM, 0);
 
 #ifdef CONFIG_SMP
         ret = cpuhp_setup_state_nocalls(CPUHP_MM_VMSTAT_DEAD, "mm/vmstat:dead",
@@ -1857,7 +1854,7 @@ static int unusable_show(struct seq_file *m, void *arg)
         if (!node_state(pgdat->node_id, N_MEMORY))
                 return 0;
 
-        walk_zones_in_node(m, pgdat, unusable_show_print);
+        walk_zones_in_node(m, pgdat, true, unusable_show_print);
 
         return 0;
 }
@@ -1909,7 +1906,7 @@ static int extfrag_show(struct seq_file *m, void *arg)
 {
         pg_data_t *pgdat = (pg_data_t *)arg;
 
-        walk_zones_in_node(m, pgdat, extfrag_show_print);
+        walk_zones_in_node(m, pgdat, true, extfrag_show_print);
 
         return 0;
 }