diff mbox series

[v2,5/8] mm: memcontrol: rename lruvec_holds_page_lru_lock to page_matches_lruvec

Message ID 20210416051407.54878-6-songmuchun@bytedance.com (mailing list archive)
State New
Headers show
Series memcontrol code cleanup and simplification | expand

Commit Message

Muchun Song April 16, 2021, 5:14 a.m. UTC
lruvec_holds_page_lru_lock() doesn't check anything about locking and is
used to check whether the page belongs to the lruvec. So rename it to
page_matches_lruvec().

Signed-off-by: Muchun Song <songmuchun@bytedance.com>
---
 include/linux/memcontrol.h | 7 +++----
 mm/vmscan.c                | 2 +-
 2 files changed, 4 insertions(+), 5 deletions(-)

Comments

Michal Hocko April 16, 2021, 6:01 a.m. UTC | #1
On Fri 16-04-21 13:14:04, Muchun Song wrote:
> lruvec_holds_page_lru_lock() doesn't check anything about locking and is
> used to check whether the page belongs to the lruvec. So rename it to
> page_matches_lruvec().
> 
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>

Acked-by: Michal Hocko <mhocko@suse.com>

Thanks

> ---
>  include/linux/memcontrol.h | 7 +++----
>  mm/vmscan.c                | 2 +-
>  2 files changed, 4 insertions(+), 5 deletions(-)
> 
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index 2fc728492c9b..40b0c31ea4ba 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -1492,8 +1492,7 @@ static inline void unlock_page_lruvec_irqrestore(struct lruvec *lruvec,
>  	spin_unlock_irqrestore(&lruvec->lru_lock, flags);
>  }
>  
> -static inline bool lruvec_holds_page_lru_lock(struct page *page,
> -					      struct lruvec *lruvec)
> +static inline bool page_matches_lruvec(struct page *page, struct lruvec *lruvec)
>  {
>  	return lruvec_pgdat(lruvec) == page_pgdat(page) &&
>  	       lruvec_memcg(lruvec) == page_memcg(page);
> @@ -1504,7 +1503,7 @@ static inline struct lruvec *relock_page_lruvec_irq(struct page *page,
>  		struct lruvec *locked_lruvec)
>  {
>  	if (locked_lruvec) {
> -		if (lruvec_holds_page_lru_lock(page, locked_lruvec))
> +		if (page_matches_lruvec(page, locked_lruvec))
>  			return locked_lruvec;
>  
>  		unlock_page_lruvec_irq(locked_lruvec);
> @@ -1518,7 +1517,7 @@ static inline struct lruvec *relock_page_lruvec_irqsave(struct page *page,
>  		struct lruvec *locked_lruvec, unsigned long *flags)
>  {
>  	if (locked_lruvec) {
> -		if (lruvec_holds_page_lru_lock(page, locked_lruvec))
> +		if (page_matches_lruvec(page, locked_lruvec))
>  			return locked_lruvec;
>  
>  		unlock_page_lruvec_irqrestore(locked_lruvec, *flags);
> diff --git a/mm/vmscan.c b/mm/vmscan.c
> index bb8321026c0c..2bc5cf409958 100644
> --- a/mm/vmscan.c
> +++ b/mm/vmscan.c
> @@ -2062,7 +2062,7 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
>  		 * All pages were isolated from the same lruvec (and isolation
>  		 * inhibits memcg migration).
>  		 */
> -		VM_BUG_ON_PAGE(!lruvec_holds_page_lru_lock(page, lruvec), page);
> +		VM_BUG_ON_PAGE(!page_matches_lruvec(page, lruvec), page);
>  		add_page_to_lru_list(page, lruvec);
>  		nr_pages = thp_nr_pages(page);
>  		nr_moved += nr_pages;
> -- 
> 2.11.0
Johannes Weiner April 16, 2021, 3:20 p.m. UTC | #2
On Fri, Apr 16, 2021 at 01:14:04PM +0800, Muchun Song wrote:
> lruvec_holds_page_lru_lock() doesn't check anything about locking and is
> used to check whether the page belongs to the lruvec. So rename it to
> page_matches_lruvec().
> 
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>

The rename makes sense, since the previous name was defined by a
specific use case rather than what it does. That said, it did imply a
lock context that makes the test result stable. Without that the
function could use a short comment, IMO. How about:

/* Test requires a stable page->memcg binding, see page_memcg() */

With that,
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Shakeel Butt April 16, 2021, 3:34 p.m. UTC | #3
On Thu, Apr 15, 2021 at 10:16 PM Muchun Song <songmuchun@bytedance.com> wrote:
>
> lruvec_holds_page_lru_lock() doesn't check anything about locking and is
> used to check whether the page belongs to the lruvec. So rename it to
> page_matches_lruvec().
>
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>

Reviewed-by: Shakeel Butt <shakeelb@google.com>
Muchun Song April 17, 2021, 2:52 a.m. UTC | #4
On Fri, Apr 16, 2021 at 11:20 PM Johannes Weiner <hannes@cmpxchg.org> wrote:
>
> On Fri, Apr 16, 2021 at 01:14:04PM +0800, Muchun Song wrote:
> > lruvec_holds_page_lru_lock() doesn't check anything about locking and is
> > used to check whether the page belongs to the lruvec. So rename it to
> > page_matches_lruvec().
> >
> > Signed-off-by: Muchun Song <songmuchun@bytedance.com>
>
> The rename makes sense, since the previous name was defined by a
> specific use case rather than what it does. That said, it did imply a
> lock context that makes the test result stable. Without that the
> function could use a short comment, IMO. How about:
>
> /* Test requires a stable page->memcg binding, see page_memcg() */

Make sense. I will add this comment.

>
> With that,
> Acked-by: Johannes Weiner <hannes@cmpxchg.org>

Thanks.
diff mbox series

Patch

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 2fc728492c9b..40b0c31ea4ba 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1492,8 +1492,7 @@  static inline void unlock_page_lruvec_irqrestore(struct lruvec *lruvec,
 	spin_unlock_irqrestore(&lruvec->lru_lock, flags);
 }
 
-static inline bool lruvec_holds_page_lru_lock(struct page *page,
-					      struct lruvec *lruvec)
+static inline bool page_matches_lruvec(struct page *page, struct lruvec *lruvec)
 {
 	return lruvec_pgdat(lruvec) == page_pgdat(page) &&
 	       lruvec_memcg(lruvec) == page_memcg(page);
@@ -1504,7 +1503,7 @@  static inline struct lruvec *relock_page_lruvec_irq(struct page *page,
 		struct lruvec *locked_lruvec)
 {
 	if (locked_lruvec) {
-		if (lruvec_holds_page_lru_lock(page, locked_lruvec))
+		if (page_matches_lruvec(page, locked_lruvec))
 			return locked_lruvec;
 
 		unlock_page_lruvec_irq(locked_lruvec);
@@ -1518,7 +1517,7 @@  static inline struct lruvec *relock_page_lruvec_irqsave(struct page *page,
 		struct lruvec *locked_lruvec, unsigned long *flags)
 {
 	if (locked_lruvec) {
-		if (lruvec_holds_page_lru_lock(page, locked_lruvec))
+		if (page_matches_lruvec(page, locked_lruvec))
 			return locked_lruvec;
 
 		unlock_page_lruvec_irqrestore(locked_lruvec, *flags);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index bb8321026c0c..2bc5cf409958 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2062,7 +2062,7 @@  static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
 		 * All pages were isolated from the same lruvec (and isolation
 		 * inhibits memcg migration).
 		 */
-		VM_BUG_ON_PAGE(!lruvec_holds_page_lru_lock(page, lruvec), page);
+		VM_BUG_ON_PAGE(!page_matches_lruvec(page, lruvec), page);
 		add_page_to_lru_list(page, lruvec);
 		nr_pages = thp_nr_pages(page);
 		nr_moved += nr_pages;