On 02/11/2023 13:43, Huang, Ying wrote:
> Li Zhijian <lizhijian@xxxxxxxxxxx> writes:
>
>> This is a prepare to improve the demotion profiling in the later
>> patches.
>>
>> Per-node demotion stats help users to quickly identify which
>> node is in hige stree, and take some special operations if needed.
>>
>> Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx>
>> ---
>> include/linux/mmzone.h | 4 ++++
>> include/linux/vm_event_item.h | 3 ---
>> mm/vmscan.c | 3 ++-
>> mm/vmstat.c | 6 +++---
>> 4 files changed, 9 insertions(+), 7 deletions(-)
>>
>> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
>> index 4106fbc5b4b3..ad0309eea850 100644
>> --- a/include/linux/mmzone.h
>> +++ b/include/linux/mmzone.h
>> @@ -206,6 +206,10 @@ enum node_stat_item {
>> #ifdef CONFIG_NUMA_BALANCING
>> PGPROMOTE_SUCCESS, /* promote successfully */
>> PGPROMOTE_CANDIDATE, /* candidate pages to promote */
>> + /* PGDEMOTE_*: pages demoted */
>> + PGDEMOTE_KSWAPD,
>> + PGDEMOTE_DIRECT,
>> + PGDEMOTE_KHUGEPAGED,
>> #endif
>> NR_VM_NODE_STAT_ITEMS
>> };
>> diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
>> index 8abfa1240040..d1b847502f09 100644
>> --- a/include/linux/vm_event_item.h
>> +++ b/include/linux/vm_event_item.h
>> @@ -41,9 +41,6 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
>> PGSTEAL_KSWAPD,
>> PGSTEAL_DIRECT,
>> PGSTEAL_KHUGEPAGED,
>> - PGDEMOTE_KSWAPD,
>> - PGDEMOTE_DIRECT,
>> - PGDEMOTE_KHUGEPAGED,
>> PGSCAN_KSWAPD,
>> PGSCAN_DIRECT,
>> PGSCAN_KHUGEPAGED,
>> diff --git a/mm/vmscan.c b/mm/vmscan.c
>> index 6f13394b112e..2f1fb4ec3235 100644
>> --- a/mm/vmscan.c
>> +++ b/mm/vmscan.c
>> @@ -1678,7 +1678,8 @@ static unsigned int demote_folio_list(struct list_head *demote_folios,
>> (unsigned long)&mtc, MIGRATE_ASYNC, MR_DEMOTION,
>> &nr_succeeded);
>>
>> - __count_vm_events(PGDEMOTE_KSWAPD + reclaimer_offset(), nr_succeeded);
>> + mod_node_page_state(NODE_DATA(target_nid),
>> + PGDEMOTE_KSWAPD + reclaimer_offset(), nr_succeeded);
>
> Think again. It seems that it's better to count demotion event for the
> source node. Because demotion comes from the memory pressure of the
> source node. The target node isn't so important. Do you agree?
Good idea, I will update it.
>
> --
> Best Regards,
> Huang, Ying
>
>>
>> return nr_succeeded;
>> }
>> diff --git a/mm/vmstat.c b/mm/vmstat.c
>> index 00e81e99c6ee..f141c48c39e4 100644
>> --- a/mm/vmstat.c
>> +++ b/mm/vmstat.c
>> @@ -1244,6 +1244,9 @@ const char * const vmstat_text[] = {
>> #ifdef CONFIG_NUMA_BALANCING
>> "pgpromote_success",
>> "pgpromote_candidate",
>> + "pgdemote_kswapd",
>> + "pgdemote_direct",
>> + "pgdemote_khugepaged",
>> #endif
>>
>> /* enum writeback_stat_item counters */
>> @@ -1275,9 +1278,6 @@ const char * const vmstat_text[] = {
>> "pgsteal_kswapd",
>> "pgsteal_direct",
>> "pgsteal_khugepaged",
>> - "pgdemote_kswapd",
>> - "pgdemote_direct",
>> - "pgdemote_khugepaged",
>> "pgscan_kswapd",
>> "pgscan_direct",
>> "pgscan_khugepaged",
