[PATCH v2] mm: drop the 'anon_' prefix for swap-out mTHP counters

[Baolin Wang <baolin.wang@linux.alibaba.com>]

The mTHP swap related counters: 'anon_swpout' and 'anon_swpout_fallback' are
confusing with an 'anon_' prefix, since the shmem can swap out non-anonymous
pages. So drop the 'anon_' prefix to keep consistent with the old swap counter
names.

Suggested-by: "Huang, Ying" <ying.huang@intel.com>
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
---
Hi Andrew,

Hope this patch can be merged into kernel 6.10-rc to maintain ABI compatibility.
Thanks.

Changes from v1:
 - Update the documentation per Barry Song.
---
 Documentation/admin-guide/mm/transhuge.rst | 4 ++--
 include/linux/huge_mm.h                    | 4 ++--
 mm/huge_memory.c                           | 8 ++++----
 mm/page_io.c                               | 2 +-
 mm/vmscan.c                                | 2 +-
 5 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/admin-guide/mm/transhuge.rst
index 076443cc10a6..d414d3f5592a 100644
--- a/Documentation/admin-guide/mm/transhuge.rst
+++ b/Documentation/admin-guide/mm/transhuge.rst
@@ -467,11 +467,11 @@ anon_fault_fallback_charge
 	instead falls back to using huge pages with lower orders or
 	small pages even though the allocation was successful.
 
-anon_swpout
+swpout
 	is incremented every time a huge page is swapped out in one
 	piece without splitting.
 
-anon_swpout_fallback
+swpout_fallback
 	is incremented if a huge page has to be split before swapout.
 	Usually because failed to allocate some continuous swap space
 	for the huge page.
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index c8d3ec116e29..8c72d3786583 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -269,8 +269,8 @@ enum mthp_stat_item {
 	MTHP_STAT_ANON_FAULT_ALLOC,
 	MTHP_STAT_ANON_FAULT_FALLBACK,
 	MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE,
-	MTHP_STAT_ANON_SWPOUT,
-	MTHP_STAT_ANON_SWPOUT_FALLBACK,
+	MTHP_STAT_SWPOUT,
+	MTHP_STAT_SWPOUT_FALLBACK,
 	__MTHP_STAT_COUNT
 };
 
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 317de2afd371..89932fd0f62e 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -558,15 +558,15 @@ static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
 DEFINE_MTHP_STAT_ATTR(anon_fault_alloc, MTHP_STAT_ANON_FAULT_ALLOC);
 DEFINE_MTHP_STAT_ATTR(anon_fault_fallback, MTHP_STAT_ANON_FAULT_FALLBACK);
 DEFINE_MTHP_STAT_ATTR(anon_fault_fallback_charge, MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE);
-DEFINE_MTHP_STAT_ATTR(anon_swpout, MTHP_STAT_ANON_SWPOUT);
-DEFINE_MTHP_STAT_ATTR(anon_swpout_fallback, MTHP_STAT_ANON_SWPOUT_FALLBACK);
+DEFINE_MTHP_STAT_ATTR(swpout, MTHP_STAT_SWPOUT);
+DEFINE_MTHP_STAT_ATTR(swpout_fallback, MTHP_STAT_SWPOUT_FALLBACK);
 
 static struct attribute *stats_attrs[] = {
 	&anon_fault_alloc_attr.attr,
 	&anon_fault_fallback_attr.attr,
 	&anon_fault_fallback_charge_attr.attr,
-	&anon_swpout_attr.attr,
-	&anon_swpout_fallback_attr.attr,
+	&swpout_attr.attr,
+	&swpout_fallback_attr.attr,
 	NULL,
 };
 
diff --git a/mm/page_io.c b/mm/page_io.c
index 46c603dddf04..0a150c240bf4 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -217,7 +217,7 @@ static inline void count_swpout_vm_event(struct folio *folio)
 		count_memcg_folio_events(folio, THP_SWPOUT, 1);
 		count_vm_event(THP_SWPOUT);
 	}
-	count_mthp_stat(folio_order(folio), MTHP_STAT_ANON_SWPOUT);
+	count_mthp_stat(folio_order(folio), MTHP_STAT_SWPOUT);
 #endif
 	count_vm_events(PSWPOUT, folio_nr_pages(folio));
 }
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 6981a71c8ef0..18b796605aa5 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1244,7 +1244,7 @@ static unsigned int shrink_folio_list(struct list_head *folio_list,
 							THP_SWPOUT_FALLBACK, 1);
 						count_vm_event(THP_SWPOUT_FALLBACK);
 					}
-					count_mthp_stat(order, MTHP_STAT_ANON_SWPOUT_FALLBACK);
+					count_mthp_stat(order, MTHP_STAT_SWPOUT_FALLBACK);
 #endif
 					if (!add_to_swap(folio))
 						goto activate_locked_split;
-- 
2.39.3