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[PATCH v6 3/3] mm: swap: Count successful mTHP ZSWAP stores in sysfs mTHP zswpout stats.

Kanchana P Sridhar posted 3 patches 1 year, 3 months ago
There is a newer version of this series
[PATCH v6 3/3] mm: swap: Count successful mTHP ZSWAP stores in sysfs mTHP zswpout stats.
Posted by Kanchana P Sridhar 1 year, 3 months ago 
Add a new MTHP_STAT_ZSWPOUT entry to the sysfs mTHP stats so that
per-order mTHP folio ZSWAP stores can be accounted.

If zswap_store() successfully swaps out an mTHP, it will be counted under
the per-order sysfs "zswpout" stats:

/sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/zswpout

Other block dev/fs mTHP swap-out events will be counted under
the existing sysfs "swpout" stats:

/sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/swpout

Based on changes made in commit 61e751c01466ffef5dc72cb64349454a691c6bfe
("mm: cleanup count_mthp_stat() definition"), this patch also moves
the call to count_mthp_stat() in count_swpout_vm_event() to be outside
the "ifdef CONFIG_TRANSPARENT_HUGEPAGE".

Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
---
 include/linux/huge_mm.h | 1 +
 mm/huge_memory.c        | 3 +++
 mm/page_io.c            | 3 ++-
 3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 4da102b74a8c..8b690328e78b 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -118,6 +118,7 @@ enum mthp_stat_item {
 	MTHP_STAT_ANON_FAULT_ALLOC,
 	MTHP_STAT_ANON_FAULT_FALLBACK,
 	MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE,
+	MTHP_STAT_ZSWPOUT,
 	MTHP_STAT_SWPOUT,
 	MTHP_STAT_SWPOUT_FALLBACK,
 	MTHP_STAT_SHMEM_ALLOC,
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 15418ffdd377..ad921c4b2ad8 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -587,6 +587,7 @@ 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(zswpout, MTHP_STAT_ZSWPOUT);
 DEFINE_MTHP_STAT_ATTR(swpout, MTHP_STAT_SWPOUT);
 DEFINE_MTHP_STAT_ATTR(swpout_fallback, MTHP_STAT_SWPOUT_FALLBACK);
 #ifdef CONFIG_SHMEM
@@ -605,6 +606,7 @@ static struct attribute *anon_stats_attrs[] = {
 	&anon_fault_fallback_attr.attr,
 	&anon_fault_fallback_charge_attr.attr,
 #ifndef CONFIG_SHMEM
+	&zswpout_attr.attr,
 	&swpout_attr.attr,
 	&swpout_fallback_attr.attr,
 #endif
@@ -637,6 +639,7 @@ static struct attribute_group file_stats_attr_grp = {
 
 static struct attribute *any_stats_attrs[] = {
 #ifdef CONFIG_SHMEM
+	&zswpout_attr.attr,
 	&swpout_attr.attr,
 	&swpout_fallback_attr.attr,
 #endif
diff --git a/mm/page_io.c b/mm/page_io.c
index b6f1519d63b0..26106e745d73 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -289,6 +289,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
 		swap_zeromap_folio_clear(folio);
 	}
 	if (zswap_store(folio)) {
+		count_mthp_stat(folio_order(folio), MTHP_STAT_ZSWPOUT);
 		folio_unlock(folio);
 		return 0;
 	}
@@ -308,8 +309,8 @@ 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_SWPOUT);
 #endif
+	count_mthp_stat(folio_order(folio), MTHP_STAT_SWPOUT);
 	count_vm_events(PSWPOUT, folio_nr_pages(folio));
 }
 
-- 
2.27.0
Re: [PATCH v6 3/3] mm: swap: Count successful mTHP ZSWAP stores in sysfs mTHP zswpout stats.
Posted by Yosry Ahmed 1 year, 2 months ago 
On Thu, Aug 29, 2024 at 2:27 PM Kanchana P Sridhar
<kanchana.p.sridhar@intel.com> wrote:
>
> Add a new MTHP_STAT_ZSWPOUT entry to the sysfs mTHP stats so that
> per-order mTHP folio ZSWAP stores can be accounted.
>
> If zswap_store() successfully swaps out an mTHP, it will be counted under
> the per-order sysfs "zswpout" stats:
>
> /sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/zswpout
>
> Other block dev/fs mTHP swap-out events will be counted under
> the existing sysfs "swpout" stats:
>
> /sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/swpout
>
> Based on changes made in commit 61e751c01466ffef5dc72cb64349454a691c6bfe
> ("mm: cleanup count_mthp_stat() definition"), this patch also moves
> the call to count_mthp_stat() in count_swpout_vm_event() to be outside
> the "ifdef CONFIG_TRANSPARENT_HUGEPAGE".

This should be in a separate change, it's irrelevant to
MTHP_STAT_ZSWPOUT being added.

>
> Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
> ---
>  include/linux/huge_mm.h | 1 +
>  mm/huge_memory.c        | 3 +++
>  mm/page_io.c            | 3 ++-
>  3 files changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
> index 4da102b74a8c..8b690328e78b 100644
> --- a/include/linux/huge_mm.h
> +++ b/include/linux/huge_mm.h
> @@ -118,6 +118,7 @@ enum mthp_stat_item {
>         MTHP_STAT_ANON_FAULT_ALLOC,
>         MTHP_STAT_ANON_FAULT_FALLBACK,
>         MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE,
> +       MTHP_STAT_ZSWPOUT,
>         MTHP_STAT_SWPOUT,
>         MTHP_STAT_SWPOUT_FALLBACK,
>         MTHP_STAT_SHMEM_ALLOC,
> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> index 15418ffdd377..ad921c4b2ad8 100644
> --- a/mm/huge_memory.c
> +++ b/mm/huge_memory.c
> @@ -587,6 +587,7 @@ 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(zswpout, MTHP_STAT_ZSWPOUT);
>  DEFINE_MTHP_STAT_ATTR(swpout, MTHP_STAT_SWPOUT);
>  DEFINE_MTHP_STAT_ATTR(swpout_fallback, MTHP_STAT_SWPOUT_FALLBACK);
>  #ifdef CONFIG_SHMEM
> @@ -605,6 +606,7 @@ static struct attribute *anon_stats_attrs[] = {
>         &anon_fault_fallback_attr.attr,
>         &anon_fault_fallback_charge_attr.attr,
>  #ifndef CONFIG_SHMEM
> +       &zswpout_attr.attr,
>         &swpout_attr.attr,
>         &swpout_fallback_attr.attr,
>  #endif
> @@ -637,6 +639,7 @@ static struct attribute_group file_stats_attr_grp = {
>
>  static struct attribute *any_stats_attrs[] = {
>  #ifdef CONFIG_SHMEM
> +       &zswpout_attr.attr,
>         &swpout_attr.attr,
>         &swpout_fallback_attr.attr,
>  #endif
> diff --git a/mm/page_io.c b/mm/page_io.c
> index b6f1519d63b0..26106e745d73 100644
> --- a/mm/page_io.c
> +++ b/mm/page_io.c
> @@ -289,6 +289,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc)
>                 swap_zeromap_folio_clear(folio);
>         }
>         if (zswap_store(folio)) {
> +               count_mthp_stat(folio_order(folio), MTHP_STAT_ZSWPOUT);
>                 folio_unlock(folio);
>                 return 0;
>         }
> @@ -308,8 +309,8 @@ 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_SWPOUT);
>  #endif
> +       count_mthp_stat(folio_order(folio), MTHP_STAT_SWPOUT);
>         count_vm_events(PSWPOUT, folio_nr_pages(folio));
>  }
>
> --
> 2.27.0
>
RE: [PATCH v6 3/3] mm: swap: Count successful mTHP ZSWAP stores in sysfs mTHP zswpout stats.
Posted by Sridhar, Kanchana P 1 year, 2 months ago 
> -----Original Message-----
> From: Yosry Ahmed <yosryahmed@google.com>
> Sent: Friday, September 20, 2024 3:58 PM
> To: Sridhar, Kanchana P <kanchana.p.sridhar@intel.com>
> Cc: linux-kernel@vger.kernel.org; linux-mm@kvack.org;
> hannes@cmpxchg.org; nphamcs@gmail.com; chengming.zhou@linux.dev;
> usamaarif642@gmail.com; ryan.roberts@arm.com; Huang, Ying
> <ying.huang@intel.com>; 21cnbao@gmail.com; akpm@linux-foundation.org;
> Zou, Nanhai <nanhai.zou@intel.com>; Feghali, Wajdi K
> <wajdi.k.feghali@intel.com>; Gopal, Vinodh <vinodh.gopal@intel.com>
> Subject: Re: [PATCH v6 3/3] mm: swap: Count successful mTHP ZSWAP stores
> in sysfs mTHP zswpout stats.
> 
> On Thu, Aug 29, 2024 at 2:27 PM Kanchana P Sridhar
> <kanchana.p.sridhar@intel.com> wrote:
> >
> > Add a new MTHP_STAT_ZSWPOUT entry to the sysfs mTHP stats so that
> > per-order mTHP folio ZSWAP stores can be accounted.
> >
> > If zswap_store() successfully swaps out an mTHP, it will be counted under
> > the per-order sysfs "zswpout" stats:
> >
> > /sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/zswpout
> >
> > Other block dev/fs mTHP swap-out events will be counted under
> > the existing sysfs "swpout" stats:
> >
> > /sys/kernel/mm/transparent_hugepage/hugepages-*kB/stats/swpout
> >
> > Based on changes made in commit
> 61e751c01466ffef5dc72cb64349454a691c6bfe
> > ("mm: cleanup count_mthp_stat() definition"), this patch also moves
> > the call to count_mthp_stat() in count_swpout_vm_event() to be outside
> > the "ifdef CONFIG_TRANSPARENT_HUGEPAGE".
> 
> This should be in a separate change, it's irrelevant to
> MTHP_STAT_ZSWPOUT being added.

Sure. I will submit this as a separate change.

Thanks,
Kanchana

> 
> >
> > Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
> > ---
> >  include/linux/huge_mm.h | 1 +
> >  mm/huge_memory.c        | 3 +++
> >  mm/page_io.c            | 3 ++-
> >  3 files changed, 6 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
> > index 4da102b74a8c..8b690328e78b 100644
> > --- a/include/linux/huge_mm.h
> > +++ b/include/linux/huge_mm.h
> > @@ -118,6 +118,7 @@ enum mthp_stat_item {
> >         MTHP_STAT_ANON_FAULT_ALLOC,
> >         MTHP_STAT_ANON_FAULT_FALLBACK,
> >         MTHP_STAT_ANON_FAULT_FALLBACK_CHARGE,
> > +       MTHP_STAT_ZSWPOUT,
> >         MTHP_STAT_SWPOUT,
> >         MTHP_STAT_SWPOUT_FALLBACK,
> >         MTHP_STAT_SHMEM_ALLOC,
> > diff --git a/mm/huge_memory.c b/mm/huge_memory.c
> > index 15418ffdd377..ad921c4b2ad8 100644
> > --- a/mm/huge_memory.c
> > +++ b/mm/huge_memory.c
> > @@ -587,6 +587,7 @@ 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(zswpout, MTHP_STAT_ZSWPOUT);
> >  DEFINE_MTHP_STAT_ATTR(swpout, MTHP_STAT_SWPOUT);
> >  DEFINE_MTHP_STAT_ATTR(swpout_fallback,
> MTHP_STAT_SWPOUT_FALLBACK);
> >  #ifdef CONFIG_SHMEM
> > @@ -605,6 +606,7 @@ static struct attribute *anon_stats_attrs[] = {
> >         &anon_fault_fallback_attr.attr,
> >         &anon_fault_fallback_charge_attr.attr,
> >  #ifndef CONFIG_SHMEM
> > +       &zswpout_attr.attr,
> >         &swpout_attr.attr,
> >         &swpout_fallback_attr.attr,
> >  #endif
> > @@ -637,6 +639,7 @@ static struct attribute_group file_stats_attr_grp = {
> >
> >  static struct attribute *any_stats_attrs[] = {
> >  #ifdef CONFIG_SHMEM
> > +       &zswpout_attr.attr,
> >         &swpout_attr.attr,
> >         &swpout_fallback_attr.attr,
> >  #endif
> > diff --git a/mm/page_io.c b/mm/page_io.c
> > index b6f1519d63b0..26106e745d73 100644
> > --- a/mm/page_io.c
> > +++ b/mm/page_io.c
> > @@ -289,6 +289,7 @@ int swap_writepage(struct page *page, struct
> writeback_control *wbc)
> >                 swap_zeromap_folio_clear(folio);
> >         }
> >         if (zswap_store(folio)) {
> > +               count_mthp_stat(folio_order(folio), MTHP_STAT_ZSWPOUT);
> >                 folio_unlock(folio);
> >                 return 0;
> >         }
> > @@ -308,8 +309,8 @@ 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_SWPOUT);
> >  #endif
> > +       count_mthp_stat(folio_order(folio), MTHP_STAT_SWPOUT);
> >         count_vm_events(PSWPOUT, folio_nr_pages(folio));
> >  }
> >
> > --
> > 2.27.0
> >
Re: [PATCH v6 3/3] mm: swap: Count successful mTHP ZSWAP stores in sysfs mTHP zswpout stats.
Posted by Nhat Pham 1 year, 3 months ago 
On Thu, Aug 29, 2024 at 2:27 PM Kanchana P Sridhar
<kanchana.p.sridhar@intel.com> wrote:
>
> Add a new MTHP_STAT_ZSWPOUT entry to the sysfs mTHP stats so that
> per-order mTHP folio ZSWAP stores can be accounted.

Can you update Documentation/admin-guide/mm/transhuge.rst?

1. New entry for zswpout.

2. Probably should clarify the semantics of swpout too - this does not
include zswap right?
RE: [PATCH v6 3/3] mm: swap: Count successful mTHP ZSWAP stores in sysfs mTHP zswpout stats.
Posted by Sridhar, Kanchana P 1 year, 2 months ago 
> -----Original Message-----
> From: Nhat Pham <nphamcs@gmail.com>
> Sent: Thursday, August 29, 2024 5:20 PM
> To: Sridhar, Kanchana P <kanchana.p.sridhar@intel.com>
> Cc: linux-kernel@vger.kernel.org; linux-mm@kvack.org;
> hannes@cmpxchg.org; yosryahmed@google.com;
> chengming.zhou@linux.dev; usamaarif642@gmail.com;
> ryan.roberts@arm.com; Huang, Ying <ying.huang@intel.com>;
> 21cnbao@gmail.com; akpm@linux-foundation.org; Zou, Nanhai
> <nanhai.zou@intel.com>; Feghali, Wajdi K <wajdi.k.feghali@intel.com>;
> Gopal, Vinodh <vinodh.gopal@intel.com>
> Subject: Re: [PATCH v6 3/3] mm: swap: Count successful mTHP ZSWAP stores
> in sysfs mTHP zswpout stats.
> 
> On Thu, Aug 29, 2024 at 2:27 PM Kanchana P Sridhar
> <kanchana.p.sridhar@intel.com> wrote:
> >
> > Add a new MTHP_STAT_ZSWPOUT entry to the sysfs mTHP stats so that
> > per-order mTHP folio ZSWAP stores can be accounted.
> 
> Can you update Documentation/admin-guide/mm/transhuge.rst?

Certainly, will do so!

> 
> 1. New entry for zswpout.
> 
> 2. Probably should clarify the semantics of swpout too - this does not
> include zswap right?

Sure. And yes, this does not include zswap.

Thanks,
Kanchana

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