Introduce a _snapshot variant of node_page_state_snapshot, similar to zone_page_state_snapshot. To be used by next patch. Signed-off-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx> --- include/linux/vmstat.h | 4 ++++ mm/vmstat.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 32 insertions(+) Index: linux/mm/vmstat.c =================================================================== --- linux.orig/mm/vmstat.c +++ linux/mm/vmstat.c @@ -1031,6 +1031,34 @@ unsigned long node_page_state(struct pgl return node_page_state_pages(pgdat, item); } + +/* + * Determine the per node value of a stat item, snapshot version + * (see comment on top zone_page_state_snapshot). + */ +unsigned long node_page_state_pages_snapshot(struct pglist_data *pgdat, + enum node_stat_item item) +{ + long x = atomic_long_read(&pgdat->vm_stat[item]); +#ifdef CONFIG_SMP + int cpu; + + for_each_online_cpu(cpu) + x += per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->vm_node_stat_diff[item]; + + if (x < 0) + x = 0; +#endif + return x; +} + +unsigned long node_page_state_snapshot(struct pglist_data *pgdat, + enum node_stat_item item) +{ + VM_WARN_ON_ONCE(vmstat_item_in_bytes(item)); + + return node_page_state_pages(pgdat, item); +} #endif #ifdef CONFIG_COMPACTION Index: linux/include/linux/vmstat.h =================================================================== --- linux.orig/include/linux/vmstat.h +++ linux/include/linux/vmstat.h @@ -262,6 +262,10 @@ extern unsigned long node_page_state(str enum node_stat_item item); extern unsigned long node_page_state_pages(struct pglist_data *pgdat, enum node_stat_item item); +extern unsigned long node_page_state_snapshot(struct pglist_data *pgdat, + enum node_stat_item item); +extern unsigned long node_page_state_pages_snapshot(struct pglist_data *pgdat, + enum node_stat_item item); extern void fold_vm_numa_events(void); #else #define sum_zone_node_page_state(node, item) global_zone_page_state(item)