Demotion will migrate pages across nodes. Previously, only the global demotion statistics were accounted for. Changed them to per-node statistics, making it easier to observe where demotion occurs on each node. This will help to identify which nodes are under pressure. This patch also make pgdemote_* behind CONFIG_NUMA_BALANCING, since demotion is not available for !CONFIG_NUMA_BALANCING With this patch, here is a sample where node0 node1 are DRAM, node3 is PMEM: Global stats: $ grep demote /proc/vmstat pgdemote_kswapd 254288 pgdemote_direct 113497 pgdemote_khugepaged 0 Per-node stats: $ grep demote /sys/devices/system/node/node0/vmstat # demotion source pgdemote_kswapd 68454 pgdemote_direct 83431 pgdemote_khugepaged 0 $ grep demote /sys/devices/system/node/node1/vmstat # demotion source pgdemote_kswapd 185834 pgdemote_direct 30066 pgdemote_khugepaged 0 $ grep demote /sys/devices/system/node/node3/vmstat # demotion target pgdemote_kswapd 0 pgdemote_direct 0 pgdemote_khugepaged 0 Reported-by: kernel test robot <lkp@xxxxxxxxx> # compling errors Closes: https://lore.kernel.org/oe-kbuild-all/202311030137.Vu2ki6zm-lkp@xxxxxxxxx/ Acked-by: "Huang, Ying" <ying.huang@xxxxxxxxx> Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx> --- V2: split it as a separate patch from previous patch set. account them to the source node instead destination and add Acked-by # Huang, Ying --- include/linux/mmzone.h | 4 ++++ include/linux/vm_event_item.h | 3 --- mm/vmscan.c | 12 ++++++++---- mm/vmstat.c | 6 +++--- 4 files changed, 15 insertions(+), 10 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..cc70dcefc60a 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1110,12 +1110,14 @@ void drop_slab(void) static int reclaimer_offset(void) { +#ifdef CONFIG_NUMA_BALANCING BUILD_BUG_ON(PGSTEAL_DIRECT - PGSTEAL_KSWAPD != PGDEMOTE_DIRECT - PGDEMOTE_KSWAPD); - BUILD_BUG_ON(PGSTEAL_DIRECT - PGSTEAL_KSWAPD != - PGSCAN_DIRECT - PGSCAN_KSWAPD); BUILD_BUG_ON(PGSTEAL_KHUGEPAGED - PGSTEAL_KSWAPD != PGDEMOTE_KHUGEPAGED - PGDEMOTE_KSWAPD); +#endif + BUILD_BUG_ON(PGSTEAL_DIRECT - PGSTEAL_KSWAPD != + PGSCAN_DIRECT - PGSCAN_KSWAPD); BUILD_BUG_ON(PGSTEAL_KHUGEPAGED - PGSTEAL_KSWAPD != PGSCAN_KHUGEPAGED - PGSCAN_KSWAPD); @@ -1677,8 +1679,10 @@ static unsigned int demote_folio_list(struct list_head *demote_folios, migrate_pages(demote_folios, alloc_demote_folio, NULL, (unsigned long)&mtc, MIGRATE_ASYNC, MR_DEMOTION, &nr_succeeded); - - __count_vm_events(PGDEMOTE_KSWAPD + reclaimer_offset(), nr_succeeded); +#ifdef CONFIG_NUMA_BALANCING + mod_node_page_state(pgdat, PGDEMOTE_KSWAPD + reclaimer_offset(), + nr_succeeded); +#endif 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", -- 2.29.2
