Some vmstat counters are being accounted in bytes not pages, so the stat_threshold should also scale to bytes. The vmstat counters are already long type for memcg (can reference to struct lruvec_stat). For the global per-node vmstat counters also can scale to long. But the maximum vmstat threshold is 125, so the type of s32 is enough. Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> --- include/linux/mmzone.h | 17 ++++++----------- include/linux/vmstat.h | 1 - mm/vmstat.c | 24 +++++++++++++----------- 3 files changed, 19 insertions(+), 23 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 1f9c83778629..d53328551225 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -216,17 +216,12 @@ enum node_stat_item { */ static __always_inline bool vmstat_item_in_bytes(int idx) { - /* - * Global and per-node slab counters track slab pages. - * It's expected that changes are multiples of PAGE_SIZE. - * Internally values are stored in pages. - * - * Per-memcg and per-lruvec counters track memory, consumed - * by individual slab objects. These counters are actually - * byte-precise. - */ return (idx == NR_SLAB_RECLAIMABLE_B || - idx == NR_SLAB_UNRECLAIMABLE_B); + idx == NR_SLAB_UNRECLAIMABLE_B || +#if IS_ENABLED(CONFIG_SHADOW_CALL_STACK) + idx == NR_KERNEL_SCS_B || +#endif + idx == NR_KERNEL_STACK_B); } /* @@ -340,7 +335,7 @@ struct per_cpu_pageset { struct per_cpu_nodestat { s8 stat_threshold; - s8 vm_node_stat_diff[NR_VM_NODE_STAT_ITEMS]; + s32 vm_node_stat_diff[NR_VM_NODE_STAT_ITEMS]; }; #endif /* !__GENERATING_BOUNDS.H */ diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h index fd1a3d5d4926..afd84dc2398c 100644 --- a/include/linux/vmstat.h +++ b/include/linux/vmstat.h @@ -211,7 +211,6 @@ static inline unsigned long global_node_page_state(enum node_stat_item item) { long x = atomic_long_read(&vm_node_stat[item]); - VM_WARN_ON_ONCE(vmstat_item_in_bytes(item)); #ifdef CONFIG_SMP if (x < 0) x = 0; diff --git a/mm/vmstat.c b/mm/vmstat.c index 7fb0c7cb9516..25751b1d8e2e 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -341,13 +341,15 @@ void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item, long delta) { struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats; - s8 __percpu *p = pcp->vm_node_stat_diff + item; + s32 __percpu *p = pcp->vm_node_stat_diff + item; long x; long t; x = delta + __this_cpu_read(*p); t = __this_cpu_read(pcp->stat_threshold); + if (vmstat_item_in_bytes(item)) + t <<= PAGE_SHIFT; if (unlikely(abs(x) > t)) { node_page_state_add(x, pgdat, item); @@ -399,15 +401,15 @@ void __inc_zone_state(struct zone *zone, enum zone_stat_item item) void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item) { struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats; - s8 __percpu *p = pcp->vm_node_stat_diff + item; - s8 v, t; + s32 __percpu *p = pcp->vm_node_stat_diff + item; + s32 v, t; VM_WARN_ON_ONCE(vmstat_item_in_bytes(item)); v = __this_cpu_inc_return(*p); t = __this_cpu_read(pcp->stat_threshold); if (unlikely(v > t)) { - s8 overstep = t >> 1; + s32 overstep = t >> 1; node_page_state_add(v + overstep, pgdat, item); __this_cpu_write(*p, -overstep); @@ -445,8 +447,8 @@ void __dec_zone_state(struct zone *zone, enum zone_stat_item item) void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item) { struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats; - s8 __percpu *p = pcp->vm_node_stat_diff + item; - s8 v, t; + s32 __percpu *p = pcp->vm_node_stat_diff + item; + s32 v, t; VM_WARN_ON_ONCE(vmstat_item_in_bytes(item)); @@ -546,7 +548,7 @@ static inline void mod_node_state(struct pglist_data *pgdat, enum node_stat_item item, int delta, int overstep_mode) { struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats; - s8 __percpu *p = pcp->vm_node_stat_diff + item; + s32 __percpu *p = pcp->vm_node_stat_diff + item; long o, n, t, z; do { @@ -563,6 +565,8 @@ static inline void mod_node_state(struct pglist_data *pgdat, * for all cpus in a node. */ t = this_cpu_read(pcp->stat_threshold); + if (vmstat_item_in_bytes(item)) + t <<= PAGE_SHIFT; o = this_cpu_read(*p); n = delta + o; @@ -829,7 +833,7 @@ static int refresh_cpu_vm_stats(bool do_pagesets) struct per_cpu_nodestat __percpu *p = pgdat->per_cpu_nodestats; for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { - int v; + s32 v; v = this_cpu_xchg(p->vm_node_stat_diff[i], 0); if (v) { @@ -899,7 +903,7 @@ void cpu_vm_stats_fold(int cpu) for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) if (p->vm_node_stat_diff[i]) { - int v; + s32 v; v = p->vm_node_stat_diff[i]; p->vm_node_stat_diff[i] = 0; @@ -1017,8 +1021,6 @@ unsigned long node_page_state(struct pglist_data *pgdat, { long x = atomic_long_read(&pgdat->vm_stat[item]); - VM_WARN_ON_ONCE(vmstat_item_in_bytes(item)); - #ifdef CONFIG_SMP if (x < 0) x = 0; -- 2.11.0