[v5,2/3] mm: add system wide stats items category

Commit Message

Pasha Tatashin Aug. 9, 2024, 7:10 p.m. UTC

/proc/vmstat contains events and stats, events can only grow, but stats
can grow and shrink.

vmstat has the following:
-------------------------
NR_VM_ZONE_STAT_ITEMS:	per-zone stats
NR_VM_NUMA_EVENT_ITEMS:	per-numa events
NR_VM_NODE_STAT_ITEMS:	per-numa stats
NR_VM_WRITEBACK_STAT_ITEMS:	system-wide background-writeback and
				dirty-throttling tresholds.
NR_VM_EVENT_ITEMS:	system-wide events
-------------------------

Rename NR_VM_WRITEBACK_STAT_ITEMS to NR_VM_STAT_ITEMS, to track the
system-wide stats, we are going to add per-page metadata stats to this
category in the next patch.

Also delete unused writeback_stat_name() function.

Suggested-by: Yosry Ahmed <[e-mail]>
Signed-off-by: Pasha Tatashin <[e-mail]>
Acked-by: David Hildenbrand <[e-mail]>
---
 include/linux/vmstat.h | 15 ++++-----------
 mm/vmstat.c            |  6 +++---
 2 files changed, 7 insertions(+), 14 deletions(-)

Comments

David Rientjes Aug. 11, 2024, 8:24 p.m. UTC | #1

On Fri, 9 Aug 2024, Pasha Tatashin wrote:

> /proc/vmstat contains events and stats, events can only grow, but stats
> can grow and shrink.
> 
> vmstat has the following:
> -------------------------
> NR_VM_ZONE_STAT_ITEMS:	per-zone stats
> NR_VM_NUMA_EVENT_ITEMS:	per-numa events
> NR_VM_NODE_STAT_ITEMS:	per-numa stats
> NR_VM_WRITEBACK_STAT_ITEMS:	system-wide background-writeback and
> 				dirty-throttling tresholds.
> NR_VM_EVENT_ITEMS:	system-wide events
> -------------------------
> 
> Rename NR_VM_WRITEBACK_STAT_ITEMS to NR_VM_STAT_ITEMS, to track the
> system-wide stats, we are going to add per-page metadata stats to this
> category in the next patch.
> 
> Also delete unused writeback_stat_name() function.
> 
> Suggested-by: Yosry Ahmed <[e-mail]>
> Signed-off-by: Pasha Tatashin <[e-mail]>
> Acked-by: David Hildenbrand <[e-mail]>

Acked-by: David Rientjes <[e-mail]>

Patch

diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
index 23cd17942036..9ab4fa5e09b5 100644
--- a/include/linux/vmstat.h
+++ b/include/linux/vmstat.h
@@ -34,10 +34,11 @@  struct reclaim_stat {
 	unsigned nr_lazyfree_fail;
 };
 
-enum writeback_stat_item {
+/* Stat data for system wide items */
+enum vm_stat_item {
 	NR_DIRTY_THRESHOLD,
 	NR_DIRTY_BG_THRESHOLD,
-	NR_VM_WRITEBACK_STAT_ITEMS,
+	NR_VM_STAT_ITEMS,
 };
 
 #ifdef CONFIG_VM_EVENT_COUNTERS
@@ -514,21 +515,13 @@  static inline const char *lru_list_name(enum lru_list lru)
 	return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
 }
 
-static inline const char *writeback_stat_name(enum writeback_stat_item item)
-{
-	return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
-			   NR_VM_NUMA_EVENT_ITEMS +
-			   NR_VM_NODE_STAT_ITEMS +
-			   item];
-}
-
 #if defined(CONFIG_VM_EVENT_COUNTERS) || defined(CONFIG_MEMCG)
 static inline const char *vm_event_name(enum vm_event_item item)
 {
 	return vmstat_text[NR_VM_ZONE_STAT_ITEMS +
 			   NR_VM_NUMA_EVENT_ITEMS +
 			   NR_VM_NODE_STAT_ITEMS +
-			   NR_VM_WRITEBACK_STAT_ITEMS +
+			   NR_VM_STAT_ITEMS +
 			   item];
 }
 #endif /* CONFIG_VM_EVENT_COUNTERS || CONFIG_MEMCG */
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 04a1cb6cc636..6f8aa4766f16 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1257,7 +1257,7 @@  const char * const vmstat_text[] = {
 	"pgdemote_khugepaged",
 	"nr_memmap",
 	"nr_memmap_boot",
-	/* enum writeback_stat_item counters */
+	/* system-wide enum vm_stat_item counters */
 	"nr_dirty_threshold",
 	"nr_dirty_background_threshold",
 
@@ -1790,7 +1790,7 @@  static const struct seq_operations zoneinfo_op = {
 #define NR_VMSTAT_ITEMS (NR_VM_ZONE_STAT_ITEMS + \
 			 NR_VM_NUMA_EVENT_ITEMS + \
 			 NR_VM_NODE_STAT_ITEMS + \
-			 NR_VM_WRITEBACK_STAT_ITEMS + \
+			 NR_VM_STAT_ITEMS + \
 			 (IS_ENABLED(CONFIG_VM_EVENT_COUNTERS) ? \
 			  NR_VM_EVENT_ITEMS : 0))
 
@@ -1827,7 +1827,7 @@  static void *vmstat_start(struct seq_file *m, loff_t *pos)
 
 	global_dirty_limits(v + NR_DIRTY_BG_THRESHOLD,
 			    v + NR_DIRTY_THRESHOLD);
-	v += NR_VM_WRITEBACK_STAT_ITEMS;
+	v += NR_VM_STAT_ITEMS;
 
 #ifdef CONFIG_VM_EVENT_COUNTERS
 	all_vm_events(v);