Commit aaf2914a authored by Barry Song's avatar Barry Song Committed by Andrew Morton
Browse files

mm: add per-order mTHP swpin counters 

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

[v-songbaohua@oppo.com: add a blank line in doc]
  Link: https://lkml.kernel.org/r/20241030233423.80759-1-21cnbao@gmail.com
Link: https://lkml.kernel.org/r/20241026082423.26298-1-21cnbao@gmail.com


Signed-off-by: default avatarBarry Song <v-songbaohua@oppo.com>
Reviewed-by: default avatarBaolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Cc: Usama Arif <usamaarif642@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent ed882add

Documentation/admin-guide/mm/transhuge.rst

+4 −0
Original line number Diff line number Diff line
@@ -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.

include/linux/huge_mm.h

+1 −0
Original line number Diff line number Diff line
@@ -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,

mm/huge_memory.c

+3 −0
Original line number Diff line number Diff line
@@ -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

mm/page_io.c

+3 −0
Original line number Diff line number Diff line
@@ -495,6 +495,7 @@ 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);
@@ -589,6 +590,7 @@ 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);
@@ -605,6 +607,7 @@ 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);