Revert "mm/vmstat.c: do not show lowmem reserve protection information of empty zone"
Subsystems (2)
PATCH 1/1 Revert "mm/vmstat.c: do not show lowmem reserve protection information of empty zone"
This reverts commit 26e7deadaae1755faf1f6d1a68988c4b8348df59.
Sonny reported that one of their tests started failing on the latest kernel on their Chrome OS platform. The root cause is that the above commit removed the protection line of empty zone, while the parser used in the test relies on the protection line to mark the end of each zone.
Let's revert it to avoid breaking userspace testing or applications.
--- mm/vmstat.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
mm/vmstat.c +6 -6
@@ -1644,12 +1644,6 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, zone->present_pages, zone_managed_pages(zone)); -/* If unpopulated, no other information is useful */ -if (!populated_zone (zone)) { -seq_putc (m,'\n' ); -return ; - } -seq_printf (m,"\n protection: (%ld" , zone->lowmem_reserve[0 ]);
@@ -1657,6 +1651,12 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,seq_printf (m,", %ld" , zone->lowmem_reserve[i]);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" ,zone_stat_name (i),zone_page_state (zone, i));
Signature · 1 line
2.17.2
Quoted 37 lines · Baoquan He
This reverts commit
26e7deadaae1755faf1f6d1a68988c4b8348df59.Sonny reported that one of their tests started failing on the latest kernel on their Chrome OS platform. The root cause is that the above commit removed the protection line of empty zone, while the parser used in the test relies on the protection line to mark the end of each zone.
Let's revert it to avoid breaking userspace testing or applications.
Cc <[email protected]> # 5.8.xReported-by Sonny Rao <[email protected]>Signed-off-by Baoquan He <[email protected]>--- mm/vmstat.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)mm/vmstat.c +0
-6@@ -1644,12 +1644,6 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, zone->present_pages, zone_managed_pages(zone)); -/* If unpopulated, no other information is useful */ -if (!populated_zone (zone)) { -seq_putc (m,'\n' ); -return ; - } -seq_printf (m,"\n protection: (%ld" , zone->lowmem_reserve[0 ]);@@ -1657,6 +1651,12 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,seq_printf (m,", %ld" , zone->lowmem_reserve[i]);seq_putc (m,')' );
mm/vmstat.c static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, · line 1662
Quoted 10 lines
mm/vmstat.c +6
-0+/* 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" ,zone_stat_name (i),zone_page_state (zone, i));
Signature · 3 lines
Thanks, David / dhildenb
Quoted 9 lines · Baoquan He
This reverts commit
26e7deadaae1755faf1f6d1a68988c4b8348df59.Sonny reported that one of their tests started failing on the latest kernel on their Chrome OS platform. The root cause is that the above commit removed the protection line of empty zone, while the parser used in the test relies on the protection line to mark the end of each zone.
Let's revert it to avoid breaking userspace testing or applications.
No objection since I noted userspace parsing as a potential risk in
https://marc.info/?l=linux-mm&m=158507790824995 but I didn't catch this earlier patch which could have led to the same thing.