From: Barry Song <v-songbaohua@xxxxxxxx>
This helps profile the sizes of folios being swapped in. Currently,
only mTHP swap-out is being counted.
The new interface can be found at:
/sys/kernel/mm/transparent_hugepage/hugepages-<size>/stats
swpin
For example,
cat /sys/kernel/mm/transparent_hugepage/hugepages-64kB/stats/swpin
12809
cat /sys/kernel/mm/transparent_hugepage/hugepages-32kB/stats/swpin
4763
Signed-off-by: Barry Song <v-songbaohua@xxxxxxxx>
Reviewed-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Chris Li <chrisl@xxxxxxxxxx>
Cc: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Cc: "Huang, Ying" <ying.huang@xxxxxxxxx>
Cc: Kairui Song <kasong@xxxxxxxxxxx>
Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
Cc: Kanchana P Sridhar <kanchana.p.sridhar@xxxxxxxxx>
Cc: Usama Arif <usamaarif642@xxxxxxxxx>
---
-v2:
* collect Baolin's reviewed-by and David's acked-by, thanks!
* add some examples for the interface in the changelog, Per
Huang, Ying. thanks!
* add a blank line in doc which was missed in v1.
Documentation/admin-guide/mm/transhuge.rst | 4 ++++
include/linux/huge_mm.h | 1 +
mm/huge_memory.c | 3 +++
mm/page_io.c | 3 +++
4 files changed, 11 insertions(+)
diff --git a/Documentation/admin-guide/mm/transhuge.rst b/Documentation/admin-guide/mm/transhuge.rst
index 2a171ed5206e..5caa3fb2feb1 100644
--- a/Documentation/admin-guide/mm/transhuge.rst
+++ b/Documentation/admin-guide/mm/transhuge.rst
@@ -534,6 +534,10 @@ zswpout
is incremented every time a huge page is swapped out to zswap in one
piece without splitting.
+swpin
+ is incremented every time a huge page is swapped in from a non-zswap
+ swap device in one piece.
+
swpout
is incremented every time a huge page is swapped out to a non-zswap
swap device in one piece without splitting.
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index c59e5aa9b081..b94c2e8ee918 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -120,6 +120,7 @@ enum mthp_stat_item {
MTHP_STAT_ANON_FAULT_FALLBACK,
MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE,
MTHP_STAT_ZSWPOUT,
+ MTHP_STAT_SWPIN,
MTHP_STAT_SWPOUT,
MTHP_STAT_SWPOUT_FALLBACK,
MTHP_STAT_SHMEM_ALLOC,
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index b26c6503e993..f92068864469 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -616,6 +616,7 @@ 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(zswpout, MTHP_STAT_ZSWPOUT);
+DEFINE_MTHP_STAT_ATTR(swpin, MTHP_STAT_SWPIN);
DEFINE_MTHP_STAT_ATTR(swpout, MTHP_STAT_SWPOUT);
DEFINE_MTHP_STAT_ATTR(swpout_fallback, MTHP_STAT_SWPOUT_FALLBACK);
#ifdef CONFIG_SHMEM
@@ -635,6 +636,7 @@ static struct attribute *anon_stats_attrs[] = {
&anon_fault_fallback_charge_attr.attr,
#ifndef CONFIG_SHMEM
&zswpout_attr.attr,
+ &swpin_attr.attr,
&swpout_attr.attr,
&swpout_fallback_attr.attr,
#endif
@@ -666,6 +668,7 @@ static struct attribute_group file_stats_attr_grp = {
static struct attribute *any_stats_attrs[] = {
#ifdef CONFIG_SHMEM
&zswpout_attr.attr,
+ &swpin_attr.attr,
&swpout_attr.attr,
&swpout_fallback_attr.attr,
#endif
diff --git a/mm/page_io.c b/mm/page_io.c
index c69fab5060a1..5d9b6e6cf96c 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -487,6 +487,7 @@ static void sio_read_complete(struct kiocb *iocb, long ret)
for (p = 0; p < sio->pages; p++) {
struct folio *folio = page_folio(sio->bvec[p].bv_page);
+ count_mthp_stat(folio_order(folio), MTHP_STAT_SWPIN);
count_memcg_folio_events(folio, PSWPIN, folio_nr_pages(folio));
folio_mark_uptodate(folio);
folio_unlock(folio);
@@ -573,6 +574,7 @@ static void swap_read_folio_bdev_sync(struct folio *folio,
* attempt to access it in the page fault retry time check.
*/
get_task_struct(current);
+ count_mthp_stat(folio_order(folio), MTHP_STAT_SWPIN);
count_memcg_folio_events(folio, PSWPIN, folio_nr_pages(folio));
count_vm_events(PSWPIN, folio_nr_pages(folio));
submit_bio_wait(&bio);
@@ -589,6 +591,7 @@ static void swap_read_folio_bdev_async(struct folio *folio,
bio->bi_iter.bi_sector = swap_folio_sector(folio);
bio->bi_end_io = end_swap_bio_read;
bio_add_folio_nofail(bio, folio, folio_size(folio), 0);
+ count_mthp_stat(folio_order(folio), MTHP_STAT_SWPIN);
count_memcg_folio_events(folio, PSWPIN, folio_nr_pages(folio));
count_vm_events(PSWPIN, folio_nr_pages(folio));
submit_bio(bio);
--
2.39.3 (Apple Git-146)
