From: Li Zhijian lizhijian@fujitsu.com
mainline inclusion from mainline-v6.8-rc1 commit 23e9f0138963ceef2a252d887534923a0502b2da category: other bugzilla: https://gitee.com/openeuler/kernel/issues/I8YBMI
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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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@fujitsu.com Signed-off-by: Li Zhijian lizhijian@fujitsu.com Acked-by: "Huang, Ying" ying.huang@intel.com Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: "Rafael J. Wysocki" rafael@kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: ZhangPeng zhangpeng362@huawei.com --- 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 d055148f47ad..cefb93d7d228 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 06d41011958c..f85742cfff07 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1114,12 +1114,14 @@ 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);
@@ -1681,8 +1683,10 @@ 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 2f716ad14168..0c56a3db0957 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",