mm: reduce noise in show_mem for lowmem allocations

While discussing early DMA pool pre-allocation failure with Christoph [1]
I have realized that the allocation failure warning is rather noisy for
constrained allocations like GFP_DMA{32}.  Those zones are usually not
populated on all nodes very often as their memory ranges are constrained.

This is an attempt to reduce the ballast that doesn't provide any relevant
information for those allocation failures investigation.  Please note that
I have only compile tested it (in my default config setup) and I am
throwing it mostly to see what people think about it.

[1] http://lkml.kernel.org/r/20220817060647.1032426-1-hch@lst.de

[mhocko@suse.com: update]
  Link: https://lkml.kernel.org/r/Yw29bmJTIkKogTiW@dhcp22.suse.cz
[mhocko@suse.com: fix build]
[akpm@linux-foundation.org: fix it for mapletree]
[akpm@linux-foundation.org: update it for Michal's update]
[mhocko@suse.com: fix arch/powerpc/xmon/xmon.c]
  Link: https://lkml.kernel.org/r/Ywh3C4dKB9B93jIy@dhcp22.suse.cz
[akpm@linux-foundation.org: fix arch/sparc/kernel/setup_32.c]
Link: https://lkml.kernel.org/r/YwScVmVofIZkopkF@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 19 insertions, 2 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 262896bd1a90..44f3c9364316 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -4322,7 +4322,7 @@ static void warn_alloc_show_mem(gfp_t gfp_mask, nodemask_t *nodemask)
 	if (!in_task() || !(gfp_mask & __GFP_DIRECT_RECLAIM))
 		filter &= ~SHOW_MEM_FILTER_NODES;
 
-	show_mem(filter, nodemask);
+	__show_mem(filter, nodemask, gfp_zone(gfp_mask));
 }
 
 void warn_alloc(gfp_t gfp_mask, nodemask_t *nodemask, const char *fmt, ...)
@@ -6050,6 +6050,15 @@ static void show_migration_types(unsigned char type)
 	printk(KERN_CONT "(%s) ", tmp);
 }
 
+static bool node_has_managed_zones(pg_data_t *pgdat, int max_zone_idx)
+{
+	int zone_idx;
+	for (zone_idx = 0; zone_idx <= max_zone_idx; zone_idx++)
+		if (zone_managed_pages(pgdat->node_zones + zone_idx))
+			return true;
+	return false;
+}
+
 /*
  * Show free area list (used inside shift_scroll-lock stuff)
  * We also calculate the percentage fragmentation. We do this by counting the
@@ -6059,7 +6068,7 @@ static void show_migration_types(unsigned char type)
  * SHOW_MEM_FILTER_NODES: suppress nodes that are not allowed by current's
  *   cpuset.
  */
-void show_free_areas(unsigned int filter, nodemask_t *nodemask)
+void __show_free_areas(unsigned int filter, nodemask_t *nodemask, int max_zone_idx)
 {
 	unsigned long free_pcp = 0;
 	int cpu, nid;
@@ -6067,6 +6076,8 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
 	pg_data_t *pgdat;
 
 	for_each_populated_zone(zone) {
+		if (zone_idx(zone) > max_zone_idx)
+			continue;
 		if (show_mem_node_skip(filter, zone_to_nid(zone), nodemask))
 			continue;
 
@@ -6104,6 +6115,8 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
 	for_each_online_pgdat(pgdat) {
 		if (show_mem_node_skip(filter, pgdat->node_id, nodemask))
 			continue;
+		if (!node_has_managed_zones(pgdat, max_zone_idx))
+			continue;
 
 		printk("Node %d"
 			" active_anon:%lukB"
@@ -6160,6 +6173,8 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
 	for_each_populated_zone(zone) {
 		int i;
 
+		if (zone_idx(zone) > max_zone_idx)
+			continue;
 		if (show_mem_node_skip(filter, zone_to_nid(zone), nodemask))
 			continue;
 
@@ -6221,6 +6236,8 @@ void show_free_areas(unsigned int filter, nodemask_t *nodemask)
 		unsigned long nr[MAX_ORDER], flags, total = 0;
 		unsigned char types[MAX_ORDER];
 
+		if (zone_idx(zone) > max_zone_idx)
+			continue;
 		if (show_mem_node_skip(filter, zone_to_nid(zone), nodemask))
 			continue;
 		show_node(zone);