On 29.09.22 00:32, Doug Berger wrote:
A zone that overlaps with another zone may span a range of pages
that are not present. In this case, displaying the start_pfn of
the zone allows the zone page range to be identified.
I don't understand the intention here.
"/* If unpopulated, no other information is useful */"
Why would the start pfn be of any use here?
What is the user visible impact without that change?
Signed-off-by: Doug Berger <opendmb@xxxxxxxxx>
---
mm/vmstat.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 90af9a8572f5..e2f19f2b7615 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1717,6 +1717,11 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
/* If unpopulated, no other information is useful */
if (!populated_zone(zone)) {
+ /* Show start_pfn for empty overlapped zones */
+ if (zone->spanned_pages)
+ seq_printf(m,
+ "\n start_pfn: %lu",
+ zone->zone_start_pfn);
seq_putc(m, '\n');
return;
}
--
Thanks,
David / dhildenb