The patch titled Subject: mm/vmstat: move pgdemote_* to per-node stats has been added to the -mm mm-unstable branch. Its filename is mm-vmstat-move-pgdemote_-to-per-node-stats.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmstat-move-pgdemote_-to-per-node-stats.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Li Zhijian <lizhijian@xxxxxxxxxxx> Subject: mm/vmstat: move pgdemote_* to per-node stats Date: Fri, 3 Nov 2023 11:14:50 +0800 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 Link: https://lkml.kernel.org/r/20231103031450.1456523-1-lizhijian@xxxxxxxxxxx Signed-off-by: Li Zhijian <lizhijian@xxxxxxxxxxx> Acked-by: "Huang, Ying" <ying.huang@xxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- 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(-) --- a/include/linux/mmzone.h~mm-vmstat-move-pgdemote_-to-per-node-stats +++ a/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 }; --- a/include/linux/vm_event_item.h~mm-vmstat-move-pgdemote_-to-per-node-stats +++ a/include/linux/vm_event_item.h @@ -41,9 +41,6 @@ enum vm_event_item { PGPGIN, PGPGOUT, PS PGSTEAL_KSWAPD, PGSTEAL_DIRECT, PGSTEAL_KHUGEPAGED, - PGDEMOTE_KSWAPD, - PGDEMOTE_DIRECT, - PGDEMOTE_KHUGEPAGED, PGSCAN_KSWAPD, PGSCAN_DIRECT, PGSCAN_KHUGEPAGED, --- a/mm/vmscan.c~mm-vmstat-move-pgdemote_-to-per-node-stats +++ a/mm/vmscan.c @@ -409,12 +409,14 @@ 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); @@ -976,8 +978,10 @@ static unsigned int demote_folio_list(st 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; } --- a/mm/vmstat.c~mm-vmstat-move-pgdemote_-to-per-node-stats +++ a/mm/vmstat.c @@ -1248,6 +1248,9 @@ 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 */ @@ -1279,9 +1282,6 @@ const char * const vmstat_text[] = { "pgsteal_kswapd", "pgsteal_direct", "pgsteal_khugepaged", - "pgdemote_kswapd", - "pgdemote_direct", - "pgdemote_khugepaged", "pgscan_kswapd", "pgscan_direct", "pgscan_khugepaged", _ Patches currently in -mm which might be from lizhijian@xxxxxxxxxxx are mm-vmstat-move-pgdemote_-to-per-node-stats.patch