Inline mem_cgroup_{charge/uncharge} and mem_cgroup_uncharge_list functions
functions to perform mem_cgroup_disabled static key check inline before
calling the main body of the function. This minimizes the memcg overhead
in the pagefault and exit_mmap paths when memcgs are disabled using
cgroup_disable=memory command-line option.
This change results in ~0.4% overhead reduction when running PFT test
comparing {CONFIG_MEMCG=n} against {CONFIG_MEMCG=y, cgroup_disable=memory}
configurationon on an 8-core ARM64 Android device.
Signed-off-by: Suren Baghdasaryan <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
---
include/linux/memcontrol.h | 28 +++++++++++++++++++++++++---
mm/memcontrol.c | 29 ++++++++++-------------------
2 files changed, 35 insertions(+), 22 deletions(-)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index bfe5c486f4ad..39fa88051a42 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -693,13 +693,35 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *memcg)
page_counter_read(&memcg->memory);
}
-int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask);
+int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
+ gfp_t gfp_mask);
+static inline int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
+ gfp_t gfp_mask)
+{
+ if (mem_cgroup_disabled())
+ return 0;
+ return __mem_cgroup_charge(page, mm, gfp_mask);
+}
+
int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
gfp_t gfp, swp_entry_t entry);
void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry);
-void mem_cgroup_uncharge(struct page *page);
-void mem_cgroup_uncharge_list(struct list_head *page_list);
+void __mem_cgroup_uncharge(struct page *page);
+static inline void mem_cgroup_uncharge(struct page *page)
+{
+ if (mem_cgroup_disabled())
+ return;
+ __mem_cgroup_uncharge(page);
+}
+
+void __mem_cgroup_uncharge_list(struct list_head *page_list);
+static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
+{
+ if (mem_cgroup_disabled())
+ return;
+ __mem_cgroup_uncharge_list(page_list);
+}
void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index a228cd51c4bd..cdaf7003b43d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6701,8 +6701,7 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root,
atomic_long_read(&parent->memory.children_low_usage)));
}
-static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
- gfp_t gfp)
+static int charge_memcg(struct page *page, struct mem_cgroup *memcg, gfp_t gfp)
{
unsigned int nr_pages = thp_nr_pages(page);
int ret;
@@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
}
/**
- * mem_cgroup_charge - charge a newly allocated page to a cgroup
+ * __mem_cgroup_charge - charge a newly allocated page to a cgroup
* @page: page to charge
* @mm: mm context of the victim
* @gfp_mask: reclaim mode
@@ -6736,16 +6735,14 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
*
* Returns 0 on success. Otherwise, an error code is returned.
*/
-int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
+int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
+ gfp_t gfp_mask)
{
struct mem_cgroup *memcg;
int ret;
- if (mem_cgroup_disabled())
- return 0;
-
memcg = get_mem_cgroup_from_mm(mm);
- ret = __mem_cgroup_charge(page, memcg, gfp_mask);
+ ret = charge_memcg(page, memcg, gfp_mask);
css_put(&memcg->css);
return ret;
@@ -6780,7 +6777,7 @@ int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
memcg = get_mem_cgroup_from_mm(mm);
rcu_read_unlock();
- ret = __mem_cgroup_charge(page, memcg, gfp);
+ ret = charge_memcg(page, memcg, gfp);
css_put(&memcg->css);
return ret;
@@ -6916,18 +6913,15 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
}
/**
- * mem_cgroup_uncharge - uncharge a page
+ * __mem_cgroup_uncharge - uncharge a page
* @page: page to uncharge
*
* Uncharge a page previously charged with mem_cgroup_charge().
*/
-void mem_cgroup_uncharge(struct page *page)
+void __mem_cgroup_uncharge(struct page *page)
{
struct uncharge_gather ug;
- if (mem_cgroup_disabled())
- return;
-
/* Don't touch page->lru of any random page, pre-check: */
if (!page_memcg(page))
return;
@@ -6938,20 +6932,17 @@ void mem_cgroup_uncharge(struct page *page)
}
/**
- * mem_cgroup_uncharge_list - uncharge a list of page
+ * __mem_cgroup_uncharge_list - uncharge a list of page
* @page_list: list of pages to uncharge
*
* Uncharge a list of pages previously charged with
* mem_cgroup_charge().
*/
-void mem_cgroup_uncharge_list(struct list_head *page_list)
+void __mem_cgroup_uncharge_list(struct list_head *page_list)
{
struct uncharge_gather ug;
struct page *page;
- if (mem_cgroup_disabled())
- return;
-
uncharge_gather_clear(&ug);
list_for_each_entry(page, page_list, lru)
uncharge_page(page, &ug);
--
2.32.0.93.g670b81a890-goog
On Sat, Jul 10, 2021 at 8:36 AM Suren Baghdasaryan <[email protected]> wrote:
>
> Inline mem_cgroup_{charge/uncharge} and mem_cgroup_uncharge_list functions
> functions to perform mem_cgroup_disabled static key check inline before
> calling the main body of the function. This minimizes the memcg overhead
> in the pagefault and exit_mmap paths when memcgs are disabled using
> cgroup_disable=memory command-line option.
> This change results in ~0.4% overhead reduction when running PFT test
> comparing {CONFIG_MEMCG=n} against {CONFIG_MEMCG=y, cgroup_disable=memory}
> configurationon on an 8-core ARM64 Android device.
>
> Signed-off-by: Suren Baghdasaryan <[email protected]>
> Reviewed-by: Shakeel Butt <[email protected]>
Reviewed-by: Muchun Song <[email protected]>
But some nits below.
> ---
> include/linux/memcontrol.h | 28 +++++++++++++++++++++++++---
> mm/memcontrol.c | 29 ++++++++++-------------------
> 2 files changed, 35 insertions(+), 22 deletions(-)
>
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index bfe5c486f4ad..39fa88051a42 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -693,13 +693,35 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *memcg)
> page_counter_read(&memcg->memory);
> }
>
> -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask);
> +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> + gfp_t gfp_mask);
> +static inline int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> + gfp_t gfp_mask)
> +{
> + if (mem_cgroup_disabled())
> + return 0;
> + return __mem_cgroup_charge(page, mm, gfp_mask);
> +}
> +
> int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
> gfp_t gfp, swp_entry_t entry);
> void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry);
>
> -void mem_cgroup_uncharge(struct page *page);
> -void mem_cgroup_uncharge_list(struct list_head *page_list);
> +void __mem_cgroup_uncharge(struct page *page);
> +static inline void mem_cgroup_uncharge(struct page *page)
> +{
> + if (mem_cgroup_disabled())
> + return;
> + __mem_cgroup_uncharge(page);
> +}
> +
> +void __mem_cgroup_uncharge_list(struct list_head *page_list);
> +static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
> +{
> + if (mem_cgroup_disabled())
> + return;
> + __mem_cgroup_uncharge_list(page_list);
> +}
>
> void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index a228cd51c4bd..cdaf7003b43d 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -6701,8 +6701,7 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root,
> atomic_long_read(&parent->memory.children_low_usage)));
> }
>
> -static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> - gfp_t gfp)
> +static int charge_memcg(struct page *page, struct mem_cgroup *memcg, gfp_t gfp)
> {
> unsigned int nr_pages = thp_nr_pages(page);
> int ret;
> @@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> }
>
> /**
> - * mem_cgroup_charge - charge a newly allocated page to a cgroup
> + * __mem_cgroup_charge - charge a newly allocated page to a cgroup
> * @page: page to charge
> * @mm: mm context of the victim
> * @gfp_mask: reclaim mode
> @@ -6736,16 +6735,14 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> *
> * Returns 0 on success. Otherwise, an error code is returned.
> */
> -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
> +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> + gfp_t gfp_mask)
> {
> struct mem_cgroup *memcg;
> int ret;
>
> - if (mem_cgroup_disabled())
> - return 0;
> -
> memcg = get_mem_cgroup_from_mm(mm);
> - ret = __mem_cgroup_charge(page, memcg, gfp_mask);
> + ret = charge_memcg(page, memcg, gfp_mask);
> css_put(&memcg->css);
>
> return ret;
> @@ -6780,7 +6777,7 @@ int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
> memcg = get_mem_cgroup_from_mm(mm);
> rcu_read_unlock();
>
> - ret = __mem_cgroup_charge(page, memcg, gfp);
> + ret = charge_memcg(page, memcg, gfp);
>
> css_put(&memcg->css);
> return ret;
> @@ -6916,18 +6913,15 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
> }
>
> /**
> - * mem_cgroup_uncharge - uncharge a page
> + * __mem_cgroup_uncharge - uncharge a page
> * @page: page to uncharge
> *
> * Uncharge a page previously charged with mem_cgroup_charge().
The comment here also needs to be updated.
mem_cgroup_uncharge() -> __mem_cgroup_uncharge()
> */
> -void mem_cgroup_uncharge(struct page *page)
> +void __mem_cgroup_uncharge(struct page *page)
> {
> struct uncharge_gather ug;
>
> - if (mem_cgroup_disabled())
> - return;
> -
> /* Don't touch page->lru of any random page, pre-check: */
> if (!page_memcg(page))
> return;
> @@ -6938,20 +6932,17 @@ void mem_cgroup_uncharge(struct page *page)
> }
>
> /**
> - * mem_cgroup_uncharge_list - uncharge a list of page
> + * __mem_cgroup_uncharge_list - uncharge a list of page
> * @page_list: list of pages to uncharge
> *
> * Uncharge a list of pages previously charged with
> * mem_cgroup_charge().
Should be __mem_cgroup_charge().
Thanks.
> */
> -void mem_cgroup_uncharge_list(struct list_head *page_list)
> +void __mem_cgroup_uncharge_list(struct list_head *page_list)
> {
> struct uncharge_gather ug;
> struct page *page;
>
> - if (mem_cgroup_disabled())
> - return;
> -
> uncharge_gather_clear(&ug);
> list_for_each_entry(page, page_list, lru)
> uncharge_page(page, &ug);
> --
> 2.32.0.93.g670b81a890-goog
>
On Fri 09-07-21 17:36:25, Suren Baghdasaryan wrote:
> Inline mem_cgroup_{charge/uncharge} and mem_cgroup_uncharge_list functions
> functions to perform mem_cgroup_disabled static key check inline before
> calling the main body of the function. This minimizes the memcg overhead
> in the pagefault and exit_mmap paths when memcgs are disabled using
> cgroup_disable=memory command-line option.
> This change results in ~0.4% overhead reduction when running PFT test
> comparing {CONFIG_MEMCG=n} against {CONFIG_MEMCG=y, cgroup_disable=memory}
> configurationon on an 8-core ARM64 Android device.
>
> Signed-off-by: Suren Baghdasaryan <[email protected]>
> Reviewed-by: Shakeel Butt <[email protected]>
With doc updated as suggested by Muchun Song
Acked-by: Michal Hocko <[email protected]>
Thanks!
> ---
> include/linux/memcontrol.h | 28 +++++++++++++++++++++++++---
> mm/memcontrol.c | 29 ++++++++++-------------------
> 2 files changed, 35 insertions(+), 22 deletions(-)
>
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index bfe5c486f4ad..39fa88051a42 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -693,13 +693,35 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *memcg)
> page_counter_read(&memcg->memory);
> }
>
> -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask);
> +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> + gfp_t gfp_mask);
> +static inline int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> + gfp_t gfp_mask)
> +{
> + if (mem_cgroup_disabled())
> + return 0;
> + return __mem_cgroup_charge(page, mm, gfp_mask);
> +}
> +
> int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
> gfp_t gfp, swp_entry_t entry);
> void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry);
>
> -void mem_cgroup_uncharge(struct page *page);
> -void mem_cgroup_uncharge_list(struct list_head *page_list);
> +void __mem_cgroup_uncharge(struct page *page);
> +static inline void mem_cgroup_uncharge(struct page *page)
> +{
> + if (mem_cgroup_disabled())
> + return;
> + __mem_cgroup_uncharge(page);
> +}
> +
> +void __mem_cgroup_uncharge_list(struct list_head *page_list);
> +static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
> +{
> + if (mem_cgroup_disabled())
> + return;
> + __mem_cgroup_uncharge_list(page_list);
> +}
>
> void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index a228cd51c4bd..cdaf7003b43d 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -6701,8 +6701,7 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root,
> atomic_long_read(&parent->memory.children_low_usage)));
> }
>
> -static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> - gfp_t gfp)
> +static int charge_memcg(struct page *page, struct mem_cgroup *memcg, gfp_t gfp)
> {
> unsigned int nr_pages = thp_nr_pages(page);
> int ret;
> @@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> }
>
> /**
> - * mem_cgroup_charge - charge a newly allocated page to a cgroup
> + * __mem_cgroup_charge - charge a newly allocated page to a cgroup
> * @page: page to charge
> * @mm: mm context of the victim
> * @gfp_mask: reclaim mode
> @@ -6736,16 +6735,14 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> *
> * Returns 0 on success. Otherwise, an error code is returned.
> */
> -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
> +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> + gfp_t gfp_mask)
> {
> struct mem_cgroup *memcg;
> int ret;
>
> - if (mem_cgroup_disabled())
> - return 0;
> -
> memcg = get_mem_cgroup_from_mm(mm);
> - ret = __mem_cgroup_charge(page, memcg, gfp_mask);
> + ret = charge_memcg(page, memcg, gfp_mask);
> css_put(&memcg->css);
>
> return ret;
> @@ -6780,7 +6777,7 @@ int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
> memcg = get_mem_cgroup_from_mm(mm);
> rcu_read_unlock();
>
> - ret = __mem_cgroup_charge(page, memcg, gfp);
> + ret = charge_memcg(page, memcg, gfp);
>
> css_put(&memcg->css);
> return ret;
> @@ -6916,18 +6913,15 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
> }
>
> /**
> - * mem_cgroup_uncharge - uncharge a page
> + * __mem_cgroup_uncharge - uncharge a page
> * @page: page to uncharge
> *
> * Uncharge a page previously charged with mem_cgroup_charge().
> */
> -void mem_cgroup_uncharge(struct page *page)
> +void __mem_cgroup_uncharge(struct page *page)
> {
> struct uncharge_gather ug;
>
> - if (mem_cgroup_disabled())
> - return;
> -
> /* Don't touch page->lru of any random page, pre-check: */
> if (!page_memcg(page))
> return;
> @@ -6938,20 +6932,17 @@ void mem_cgroup_uncharge(struct page *page)
> }
>
> /**
> - * mem_cgroup_uncharge_list - uncharge a list of page
> + * __mem_cgroup_uncharge_list - uncharge a list of page
> * @page_list: list of pages to uncharge
> *
> * Uncharge a list of pages previously charged with
> * mem_cgroup_charge().
> */
> -void mem_cgroup_uncharge_list(struct list_head *page_list)
> +void __mem_cgroup_uncharge_list(struct list_head *page_list)
> {
> struct uncharge_gather ug;
> struct page *page;
>
> - if (mem_cgroup_disabled())
> - return;
> -
> uncharge_gather_clear(&ug);
> list_for_each_entry(page, page_list, lru)
> uncharge_page(page, &ug);
> --
> 2.32.0.93.g670b81a890-goog
--
Michal Hocko
SUSE Labs
On Mon, Jul 12, 2021 at 12:15 AM Michal Hocko <[email protected]> wrote:
>
> On Fri 09-07-21 17:36:25, Suren Baghdasaryan wrote:
> > Inline mem_cgroup_{charge/uncharge} and mem_cgroup_uncharge_list functions
> > functions to perform mem_cgroup_disabled static key check inline before
> > calling the main body of the function. This minimizes the memcg overhead
> > in the pagefault and exit_mmap paths when memcgs are disabled using
> > cgroup_disable=memory command-line option.
> > This change results in ~0.4% overhead reduction when running PFT test
> > comparing {CONFIG_MEMCG=n} against {CONFIG_MEMCG=y, cgroup_disable=memory}
> > configurationon on an 8-core ARM64 Android device.
> >
> > Signed-off-by: Suren Baghdasaryan <[email protected]>
> > Reviewed-by: Shakeel Butt <[email protected]>
>
> With doc updated as suggested by Muchun Song
> Acked-by: Michal Hocko <[email protected]>
Thanks! Will fix the comment and post v4 later today.
>
> Thanks!
>
> > ---
> > include/linux/memcontrol.h | 28 +++++++++++++++++++++++++---
> > mm/memcontrol.c | 29 ++++++++++-------------------
> > 2 files changed, 35 insertions(+), 22 deletions(-)
> >
> > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> > index bfe5c486f4ad..39fa88051a42 100644
> > --- a/include/linux/memcontrol.h
> > +++ b/include/linux/memcontrol.h
> > @@ -693,13 +693,35 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *memcg)
> > page_counter_read(&memcg->memory);
> > }
> >
> > -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask);
> > +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> > + gfp_t gfp_mask);
> > +static inline int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> > + gfp_t gfp_mask)
> > +{
> > + if (mem_cgroup_disabled())
> > + return 0;
> > + return __mem_cgroup_charge(page, mm, gfp_mask);
> > +}
> > +
> > int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
> > gfp_t gfp, swp_entry_t entry);
> > void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry);
> >
> > -void mem_cgroup_uncharge(struct page *page);
> > -void mem_cgroup_uncharge_list(struct list_head *page_list);
> > +void __mem_cgroup_uncharge(struct page *page);
> > +static inline void mem_cgroup_uncharge(struct page *page)
> > +{
> > + if (mem_cgroup_disabled())
> > + return;
> > + __mem_cgroup_uncharge(page);
> > +}
> > +
> > +void __mem_cgroup_uncharge_list(struct list_head *page_list);
> > +static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
> > +{
> > + if (mem_cgroup_disabled())
> > + return;
> > + __mem_cgroup_uncharge_list(page_list);
> > +}
> >
> > void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
> >
> > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > index a228cd51c4bd..cdaf7003b43d 100644
> > --- a/mm/memcontrol.c
> > +++ b/mm/memcontrol.c
> > @@ -6701,8 +6701,7 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root,
> > atomic_long_read(&parent->memory.children_low_usage)));
> > }
> >
> > -static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> > - gfp_t gfp)
> > +static int charge_memcg(struct page *page, struct mem_cgroup *memcg, gfp_t gfp)
> > {
> > unsigned int nr_pages = thp_nr_pages(page);
> > int ret;
> > @@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> > }
> >
> > /**
> > - * mem_cgroup_charge - charge a newly allocated page to a cgroup
> > + * __mem_cgroup_charge - charge a newly allocated page to a cgroup
> > * @page: page to charge
> > * @mm: mm context of the victim
> > * @gfp_mask: reclaim mode
> > @@ -6736,16 +6735,14 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> > *
> > * Returns 0 on success. Otherwise, an error code is returned.
> > */
> > -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
> > +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> > + gfp_t gfp_mask)
> > {
> > struct mem_cgroup *memcg;
> > int ret;
> >
> > - if (mem_cgroup_disabled())
> > - return 0;
> > -
> > memcg = get_mem_cgroup_from_mm(mm);
> > - ret = __mem_cgroup_charge(page, memcg, gfp_mask);
> > + ret = charge_memcg(page, memcg, gfp_mask);
> > css_put(&memcg->css);
> >
> > return ret;
> > @@ -6780,7 +6777,7 @@ int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
> > memcg = get_mem_cgroup_from_mm(mm);
> > rcu_read_unlock();
> >
> > - ret = __mem_cgroup_charge(page, memcg, gfp);
> > + ret = charge_memcg(page, memcg, gfp);
> >
> > css_put(&memcg->css);
> > return ret;
> > @@ -6916,18 +6913,15 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
> > }
> >
> > /**
> > - * mem_cgroup_uncharge - uncharge a page
> > + * __mem_cgroup_uncharge - uncharge a page
> > * @page: page to uncharge
> > *
> > * Uncharge a page previously charged with mem_cgroup_charge().
> > */
> > -void mem_cgroup_uncharge(struct page *page)
> > +void __mem_cgroup_uncharge(struct page *page)
> > {
> > struct uncharge_gather ug;
> >
> > - if (mem_cgroup_disabled())
> > - return;
> > -
> > /* Don't touch page->lru of any random page, pre-check: */
> > if (!page_memcg(page))
> > return;
> > @@ -6938,20 +6932,17 @@ void mem_cgroup_uncharge(struct page *page)
> > }
> >
> > /**
> > - * mem_cgroup_uncharge_list - uncharge a list of page
> > + * __mem_cgroup_uncharge_list - uncharge a list of page
> > * @page_list: list of pages to uncharge
> > *
> > * Uncharge a list of pages previously charged with
> > * mem_cgroup_charge().
> > */
> > -void mem_cgroup_uncharge_list(struct list_head *page_list)
> > +void __mem_cgroup_uncharge_list(struct list_head *page_list)
> > {
> > struct uncharge_gather ug;
> > struct page *page;
> >
> > - if (mem_cgroup_disabled())
> > - return;
> > -
> > uncharge_gather_clear(&ug);
> > list_for_each_entry(page, page_list, lru)
> > uncharge_page(page, &ug);
> > --
> > 2.32.0.93.g670b81a890-goog
>
> --
> Michal Hocko
> SUSE Labs
On Sat, Jul 10, 2021 at 4:08 AM Muchun Song <[email protected]> wrote:
>
> On Sat, Jul 10, 2021 at 8:36 AM Suren Baghdasaryan <[email protected]> wrote:
> >
> > Inline mem_cgroup_{charge/uncharge} and mem_cgroup_uncharge_list functions
> > functions to perform mem_cgroup_disabled static key check inline before
> > calling the main body of the function. This minimizes the memcg overhead
> > in the pagefault and exit_mmap paths when memcgs are disabled using
> > cgroup_disable=memory command-line option.
> > This change results in ~0.4% overhead reduction when running PFT test
> > comparing {CONFIG_MEMCG=n} against {CONFIG_MEMCG=y, cgroup_disable=memory}
> > configurationon on an 8-core ARM64 Android device.
> >
> > Signed-off-by: Suren Baghdasaryan <[email protected]>
> > Reviewed-by: Shakeel Butt <[email protected]>
>
> Reviewed-by: Muchun Song <[email protected]>
>
> But some nits below.
>
> > ---
> > include/linux/memcontrol.h | 28 +++++++++++++++++++++++++---
> > mm/memcontrol.c | 29 ++++++++++-------------------
> > 2 files changed, 35 insertions(+), 22 deletions(-)
> >
> > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> > index bfe5c486f4ad..39fa88051a42 100644
> > --- a/include/linux/memcontrol.h
> > +++ b/include/linux/memcontrol.h
> > @@ -693,13 +693,35 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *memcg)
> > page_counter_read(&memcg->memory);
> > }
> >
> > -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask);
> > +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> > + gfp_t gfp_mask);
> > +static inline int mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> > + gfp_t gfp_mask)
> > +{
> > + if (mem_cgroup_disabled())
> > + return 0;
> > + return __mem_cgroup_charge(page, mm, gfp_mask);
> > +}
> > +
> > int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
> > gfp_t gfp, swp_entry_t entry);
> > void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry);
> >
> > -void mem_cgroup_uncharge(struct page *page);
> > -void mem_cgroup_uncharge_list(struct list_head *page_list);
> > +void __mem_cgroup_uncharge(struct page *page);
> > +static inline void mem_cgroup_uncharge(struct page *page)
> > +{
> > + if (mem_cgroup_disabled())
> > + return;
> > + __mem_cgroup_uncharge(page);
> > +}
> > +
> > +void __mem_cgroup_uncharge_list(struct list_head *page_list);
> > +static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
> > +{
> > + if (mem_cgroup_disabled())
> > + return;
> > + __mem_cgroup_uncharge_list(page_list);
> > +}
> >
> > void mem_cgroup_migrate(struct page *oldpage, struct page *newpage);
> >
> > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > index a228cd51c4bd..cdaf7003b43d 100644
> > --- a/mm/memcontrol.c
> > +++ b/mm/memcontrol.c
> > @@ -6701,8 +6701,7 @@ void mem_cgroup_calculate_protection(struct mem_cgroup *root,
> > atomic_long_read(&parent->memory.children_low_usage)));
> > }
> >
> > -static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> > - gfp_t gfp)
> > +static int charge_memcg(struct page *page, struct mem_cgroup *memcg, gfp_t gfp)
> > {
> > unsigned int nr_pages = thp_nr_pages(page);
> > int ret;
> > @@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> > }
> >
> > /**
> > - * mem_cgroup_charge - charge a newly allocated page to a cgroup
> > + * __mem_cgroup_charge - charge a newly allocated page to a cgroup
> > * @page: page to charge
> > * @mm: mm context of the victim
> > * @gfp_mask: reclaim mode
> > @@ -6736,16 +6735,14 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> > *
> > * Returns 0 on success. Otherwise, an error code is returned.
> > */
> > -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask)
> > +int __mem_cgroup_charge(struct page *page, struct mm_struct *mm,
> > + gfp_t gfp_mask)
> > {
> > struct mem_cgroup *memcg;
> > int ret;
> >
> > - if (mem_cgroup_disabled())
> > - return 0;
> > -
> > memcg = get_mem_cgroup_from_mm(mm);
> > - ret = __mem_cgroup_charge(page, memcg, gfp_mask);
> > + ret = charge_memcg(page, memcg, gfp_mask);
> > css_put(&memcg->css);
> >
> > return ret;
> > @@ -6780,7 +6777,7 @@ int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
> > memcg = get_mem_cgroup_from_mm(mm);
> > rcu_read_unlock();
> >
> > - ret = __mem_cgroup_charge(page, memcg, gfp);
> > + ret = charge_memcg(page, memcg, gfp);
> >
> > css_put(&memcg->css);
> > return ret;
> > @@ -6916,18 +6913,15 @@ static void uncharge_page(struct page *page, struct uncharge_gather *ug)
> > }
> >
> > /**
> > - * mem_cgroup_uncharge - uncharge a page
> > + * __mem_cgroup_uncharge - uncharge a page
> > * @page: page to uncharge
> > *
> > * Uncharge a page previously charged with mem_cgroup_charge().
>
> The comment here also needs to be updated.
>
> mem_cgroup_uncharge() -> __mem_cgroup_uncharge()
>
> > */
> > -void mem_cgroup_uncharge(struct page *page)
> > +void __mem_cgroup_uncharge(struct page *page)
> > {
> > struct uncharge_gather ug;
> >
> > - if (mem_cgroup_disabled())
> > - return;
> > -
> > /* Don't touch page->lru of any random page, pre-check: */
> > if (!page_memcg(page))
> > return;
> > @@ -6938,20 +6932,17 @@ void mem_cgroup_uncharge(struct page *page)
> > }
> >
> > /**
> > - * mem_cgroup_uncharge_list - uncharge a list of page
> > + * __mem_cgroup_uncharge_list - uncharge a list of page
> > * @page_list: list of pages to uncharge
> > *
> > * Uncharge a list of pages previously charged with
> > * mem_cgroup_charge().
>
> Should be __mem_cgroup_charge().
Fixed and posted in v4 at:
https://lore.kernel.org/patchwork/project/lkml/list/?series=507943
Thanks!
>
> Thanks.
>
> > */
> > -void mem_cgroup_uncharge_list(struct list_head *page_list)
> > +void __mem_cgroup_uncharge_list(struct list_head *page_list)
> > {
> > struct uncharge_gather ug;
> > struct page *page;
> >
> > - if (mem_cgroup_disabled())
> > - return;
> > -
> > uncharge_gather_clear(&ug);
> > list_for_each_entry(page, page_list, lru)
> > uncharge_page(page, &ug);
> > --
> > 2.32.0.93.g670b81a890-goog
> >
On Fri, Jul 09, 2021 at 05:36:25PM -0700, Suren Baghdasaryan wrote:
> @@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> }
>
> /**
> - * mem_cgroup_charge - charge a newly allocated page to a cgroup
> + * __mem_cgroup_charge - charge a newly allocated page to a cgroup
> * @page: page to charge
> * @mm: mm context of the victim
> * @gfp_mask: reclaim mode
This patch conflicts with the folio work, so I'm just rebasing the
folio patches on top of this, and I think this part of the patch is a
mistake. We don't want to document the __mem_cgroup_charge() function.
That's an implementation detail. This patch should instead have moved the
kernel-doc to memcontrol.h and continued to document mem_cgroup_charge().
On Sun, Jul 18, 2021 at 9:56 AM Matthew Wilcox <[email protected]> wrote:
>
> On Fri, Jul 09, 2021 at 05:36:25PM -0700, Suren Baghdasaryan wrote:
> > @@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> > }
> >
> > /**
> > - * mem_cgroup_charge - charge a newly allocated page to a cgroup
> > + * __mem_cgroup_charge - charge a newly allocated page to a cgroup
> > * @page: page to charge
> > * @mm: mm context of the victim
> > * @gfp_mask: reclaim mode
>
> This patch conflicts with the folio work, so I'm just rebasing the
> folio patches on top of this, and I think this part of the patch is a
> mistake. We don't want to document the __mem_cgroup_charge() function.
> That's an implementation detail. This patch should instead have moved the
> kernel-doc to memcontrol.h and continued to document mem_cgroup_charge().
Ack.
There was a v4 version of this patch:
https://lore.kernel.org/patchwork/patch/1458907 which was picked up by
Andrew already. If others agree that documentation should be moved
into the header file then I'll gladly post another version. Or I can
post a separate patch moving the documentation only. Whatever works
best. Andrew, Michal, Johannes, WDYT?
On Sun, Jul 18, 2021 at 02:25:50PM -0700, Suren Baghdasaryan wrote:
> On Sun, Jul 18, 2021 at 9:56 AM Matthew Wilcox <[email protected]> wrote:
> >
> > On Fri, Jul 09, 2021 at 05:36:25PM -0700, Suren Baghdasaryan wrote:
> > > @@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> > > }
> > >
> > > /**
> > > - * mem_cgroup_charge - charge a newly allocated page to a cgroup
> > > + * __mem_cgroup_charge - charge a newly allocated page to a cgroup
> > > * @page: page to charge
> > > * @mm: mm context of the victim
> > > * @gfp_mask: reclaim mode
> >
> > This patch conflicts with the folio work, so I'm just rebasing the
> > folio patches on top of this, and I think this part of the patch is a
> > mistake. We don't want to document the __mem_cgroup_charge() function.
> > That's an implementation detail. This patch should instead have moved the
> > kernel-doc to memcontrol.h and continued to document mem_cgroup_charge().
>
> Ack.
> There was a v4 version of this patch:
> https://lore.kernel.org/patchwork/patch/1458907 which was picked up by
> Andrew already. If others agree that documentation should be moved
> into the header file then I'll gladly post another version. Or I can
> post a separate patch moving the documentation only. Whatever works
> best. Andrew, Michal, Johannes, WDYT?
At this point, I've moved the documentation as part of the folio patch.
I'd rather not redo that patch again ...
On Sun, Jul 18, 2021 at 2:30 PM Matthew Wilcox <[email protected]> wrote:
>
> On Sun, Jul 18, 2021 at 02:25:50PM -0700, Suren Baghdasaryan wrote:
> > On Sun, Jul 18, 2021 at 9:56 AM Matthew Wilcox <[email protected]> wrote:
> > >
> > > On Fri, Jul 09, 2021 at 05:36:25PM -0700, Suren Baghdasaryan wrote:
> > > > @@ -6723,7 +6722,7 @@ static int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg,
> > > > }
> > > >
> > > > /**
> > > > - * mem_cgroup_charge - charge a newly allocated page to a cgroup
> > > > + * __mem_cgroup_charge - charge a newly allocated page to a cgroup
> > > > * @page: page to charge
> > > > * @mm: mm context of the victim
> > > > * @gfp_mask: reclaim mode
> > >
> > > This patch conflicts with the folio work, so I'm just rebasing the
> > > folio patches on top of this, and I think this part of the patch is a
> > > mistake. We don't want to document the __mem_cgroup_charge() function.
> > > That's an implementation detail. This patch should instead have moved the
> > > kernel-doc to memcontrol.h and continued to document mem_cgroup_charge().
> >
> > Ack.
> > There was a v4 version of this patch:
> > https://lore.kernel.org/patchwork/patch/1458907 which was picked up by
> > Andrew already. If others agree that documentation should be moved
> > into the header file then I'll gladly post another version. Or I can
> > post a separate patch moving the documentation only. Whatever works
> > best. Andrew, Michal, Johannes, WDYT?
>
> At this point, I've moved the documentation as part of the folio patch.
> I'd rather not redo that patch again ...
Ok. If you need me to redo anything please let me know.