| Message ID | 20210413065153.63431-5-songmuchun@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | memcontrol code cleanup and simplification | expand |
On Mon, Apr 12, 2021 at 11:57 PM Muchun Song <songmuchun@bytedance.com> wrote: > > We already have a helper lruvec_memcg() to get the memcg from lruvec, we > do not need to do it ourselves in the lruvec_holds_page_lru_lock(). So use > lruvec_memcg() instead. And if mem_cgroup_disabled() returns false, the > page_memcg(page) (the LRU pages) cannot be NULL. So remove the odd logic > of "memcg = page_memcg(page) ? : root_mem_cgroup". And use lruvec_pgdat > to simplify the code. We can have a single definition for this function > that works for !CONFIG_MEMCG, CONFIG_MEMCG + mem_cgroup_disabled() and > CONFIG_MEMCG. > > Signed-off-by: Muchun Song <songmuchun@bytedance.com> > Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Shakeel Butt <shakeelb@google.com>
On Tue, Apr 13, 2021 at 02:51:50PM +0800, Muchun Song wrote: > We already have a helper lruvec_memcg() to get the memcg from lruvec, we > do not need to do it ourselves in the lruvec_holds_page_lru_lock(). So use > lruvec_memcg() instead. And if mem_cgroup_disabled() returns false, the > page_memcg(page) (the LRU pages) cannot be NULL. So remove the odd logic > of "memcg = page_memcg(page) ? : root_mem_cgroup". And use lruvec_pgdat > to simplify the code. We can have a single definition for this function > that works for !CONFIG_MEMCG, CONFIG_MEMCG + mem_cgroup_disabled() and > CONFIG_MEMCG. > > Signed-off-by: Muchun Song <songmuchun@bytedance.com> > Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Roman Gushchin <guro@fb.com> > --- > include/linux/memcontrol.h | 31 +++++++------------------------ > 1 file changed, 7 insertions(+), 24 deletions(-) > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > index 4f49865c9958..38b8d3fb24ff 100644 > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -755,22 +755,6 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page) > return mem_cgroup_lruvec(memcg, pgdat); > } > > -static inline bool lruvec_holds_page_lru_lock(struct page *page, > - struct lruvec *lruvec) > -{ > - pg_data_t *pgdat = page_pgdat(page); > - const struct mem_cgroup *memcg; > - struct mem_cgroup_per_node *mz; > - > - if (mem_cgroup_disabled()) > - return lruvec == &pgdat->__lruvec; > - > - mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); > - memcg = page_memcg(page) ? : root_mem_cgroup; > - > - return lruvec->pgdat == pgdat && mz->memcg == memcg; > -} > - > struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); > > struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm); > @@ -1229,14 +1213,6 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page) > return &pgdat->__lruvec; > } > > -static inline bool lruvec_holds_page_lru_lock(struct page *page, > - struct lruvec *lruvec) > -{ > - pg_data_t *pgdat = page_pgdat(page); > - > - return lruvec == &pgdat->__lruvec; > -} > - > static inline void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page) > { > } > @@ -1518,6 +1494,13 @@ 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) > +{ > + return lruvec_pgdat(lruvec) == page_pgdat(page) && > + lruvec_memcg(lruvec) == page_memcg(page); > +} > + > /* Don't lock again iff page's lruvec locked */ > static inline struct lruvec *relock_page_lruvec_irq(struct page *page, > struct lruvec *locked_lruvec) > -- > 2.11.0 >
On Tue 13-04-21 14:51:50, Muchun Song wrote: > We already have a helper lruvec_memcg() to get the memcg from lruvec, we > do not need to do it ourselves in the lruvec_holds_page_lru_lock(). So use > lruvec_memcg() instead. And if mem_cgroup_disabled() returns false, the > page_memcg(page) (the LRU pages) cannot be NULL. So remove the odd logic > of "memcg = page_memcg(page) ? : root_mem_cgroup". And use lruvec_pgdat > to simplify the code. We can have a single definition for this function > that works for !CONFIG_MEMCG, CONFIG_MEMCG + mem_cgroup_disabled() and > CONFIG_MEMCG. Neat. While you are at it wouldn't it make sesne to rename the function as well. I do not want to bikeshed but this is really a misnomer. it doesn't check anything about locking. page_belongs_lruvec? > Signed-off-by: Muchun Song <songmuchun@bytedance.com> > Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> > --- > include/linux/memcontrol.h | 31 +++++++------------------------ > 1 file changed, 7 insertions(+), 24 deletions(-) > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > index 4f49865c9958..38b8d3fb24ff 100644 > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -755,22 +755,6 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page) > return mem_cgroup_lruvec(memcg, pgdat); > } > > -static inline bool lruvec_holds_page_lru_lock(struct page *page, > - struct lruvec *lruvec) > -{ > - pg_data_t *pgdat = page_pgdat(page); > - const struct mem_cgroup *memcg; > - struct mem_cgroup_per_node *mz; > - > - if (mem_cgroup_disabled()) > - return lruvec == &pgdat->__lruvec; > - > - mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); > - memcg = page_memcg(page) ? : root_mem_cgroup; > - > - return lruvec->pgdat == pgdat && mz->memcg == memcg; > -} > - > struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); > > struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm); > @@ -1229,14 +1213,6 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page) > return &pgdat->__lruvec; > } > > -static inline bool lruvec_holds_page_lru_lock(struct page *page, > - struct lruvec *lruvec) > -{ > - pg_data_t *pgdat = page_pgdat(page); > - > - return lruvec == &pgdat->__lruvec; > -} > - > static inline void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page) > { > } > @@ -1518,6 +1494,13 @@ 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) > +{ > + return lruvec_pgdat(lruvec) == page_pgdat(page) && > + lruvec_memcg(lruvec) == page_memcg(page); > +} > + > /* Don't lock again iff page's lruvec locked */ > static inline struct lruvec *relock_page_lruvec_irq(struct page *page, > struct lruvec *locked_lruvec) > -- > 2.11.0
On Wed, Apr 14, 2021 at 5:44 PM Michal Hocko <mhocko@suse.com> wrote: > > On Tue 13-04-21 14:51:50, Muchun Song wrote: > > We already have a helper lruvec_memcg() to get the memcg from lruvec, we > > do not need to do it ourselves in the lruvec_holds_page_lru_lock(). So use > > lruvec_memcg() instead. And if mem_cgroup_disabled() returns false, the > > page_memcg(page) (the LRU pages) cannot be NULL. So remove the odd logic > > of "memcg = page_memcg(page) ? : root_mem_cgroup". And use lruvec_pgdat > > to simplify the code. We can have a single definition for this function > > that works for !CONFIG_MEMCG, CONFIG_MEMCG + mem_cgroup_disabled() and > > CONFIG_MEMCG. > > Neat. While you are at it wouldn't it make sesne to rename the function > as well. I do not want to bikeshed but this is really a misnomer. it > doesn't check anything about locking. page_belongs_lruvec? Right. lruvec_holds_page_lru_lock is used to check whether the page belongs to the lruvec. page_belongs_lruvec obviously more clearer. I can rename it to page_belongs_lruvec the next version. > > > Signed-off-by: Muchun Song <songmuchun@bytedance.com> > > Acked-by: Johannes Weiner <hannes@cmpxchg.org> > > Acked-by: Michal Hocko <mhocko@suse.com> Thanks. > > > --- > > include/linux/memcontrol.h | 31 +++++++------------------------ > > 1 file changed, 7 insertions(+), 24 deletions(-) > > > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > > index 4f49865c9958..38b8d3fb24ff 100644 > > --- a/include/linux/memcontrol.h > > +++ b/include/linux/memcontrol.h > > @@ -755,22 +755,6 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page) > > return mem_cgroup_lruvec(memcg, pgdat); > > } > > > > -static inline bool lruvec_holds_page_lru_lock(struct page *page, > > - struct lruvec *lruvec) > > -{ > > - pg_data_t *pgdat = page_pgdat(page); > > - const struct mem_cgroup *memcg; > > - struct mem_cgroup_per_node *mz; > > - > > - if (mem_cgroup_disabled()) > > - return lruvec == &pgdat->__lruvec; > > - > > - mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); > > - memcg = page_memcg(page) ? : root_mem_cgroup; > > - > > - return lruvec->pgdat == pgdat && mz->memcg == memcg; > > -} > > - > > struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); > > > > struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm); > > @@ -1229,14 +1213,6 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page) > > return &pgdat->__lruvec; > > } > > > > -static inline bool lruvec_holds_page_lru_lock(struct page *page, > > - struct lruvec *lruvec) > > -{ > > - pg_data_t *pgdat = page_pgdat(page); > > - > > - return lruvec == &pgdat->__lruvec; > > -} > > - > > static inline void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page) > > { > > } > > @@ -1518,6 +1494,13 @@ 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) > > +{ > > + return lruvec_pgdat(lruvec) == page_pgdat(page) && > > + lruvec_memcg(lruvec) == page_memcg(page); > > +} > > + > > /* Don't lock again iff page's lruvec locked */ > > static inline struct lruvec *relock_page_lruvec_irq(struct page *page, > > struct lruvec *locked_lruvec) > > -- > > 2.11.0 > > -- > Michal Hocko > SUSE Labs
On Wed, Apr 14, 2021 at 06:00:42PM +0800, Muchun Song wrote: > On Wed, Apr 14, 2021 at 5:44 PM Michal Hocko <mhocko@suse.com> wrote: > > > > On Tue 13-04-21 14:51:50, Muchun Song wrote: > > > We already have a helper lruvec_memcg() to get the memcg from lruvec, we > > > do not need to do it ourselves in the lruvec_holds_page_lru_lock(). So use > > > lruvec_memcg() instead. And if mem_cgroup_disabled() returns false, the > > > page_memcg(page) (the LRU pages) cannot be NULL. So remove the odd logic > > > of "memcg = page_memcg(page) ? : root_mem_cgroup". And use lruvec_pgdat > > > to simplify the code. We can have a single definition for this function > > > that works for !CONFIG_MEMCG, CONFIG_MEMCG + mem_cgroup_disabled() and > > > CONFIG_MEMCG. > > > > Neat. While you are at it wouldn't it make sesne to rename the function > > as well. I do not want to bikeshed but this is really a misnomer. it > > doesn't check anything about locking. page_belongs_lruvec? > > Right. lruvec_holds_page_lru_lock is used to check whether > the page belongs to the lruvec. page_belongs_lruvec > obviously more clearer. I can rename it to > page_belongs_lruvec the next version. This sounds strange to me, I think 'belongs' needs a 'to' to be correct, so page_belongs_to_lruvec(). Still kind of a mouthful. page_matches_lruvec()? page_from_lruvec()?
On Wed 14-04-21 13:49:56, Johannes Weiner wrote: > On Wed, Apr 14, 2021 at 06:00:42PM +0800, Muchun Song wrote: > > On Wed, Apr 14, 2021 at 5:44 PM Michal Hocko <mhocko@suse.com> wrote: > > > > > > On Tue 13-04-21 14:51:50, Muchun Song wrote: > > > > We already have a helper lruvec_memcg() to get the memcg from lruvec, we > > > > do not need to do it ourselves in the lruvec_holds_page_lru_lock(). So use > > > > lruvec_memcg() instead. And if mem_cgroup_disabled() returns false, the > > > > page_memcg(page) (the LRU pages) cannot be NULL. So remove the odd logic > > > > of "memcg = page_memcg(page) ? : root_mem_cgroup". And use lruvec_pgdat > > > > to simplify the code. We can have a single definition for this function > > > > that works for !CONFIG_MEMCG, CONFIG_MEMCG + mem_cgroup_disabled() and > > > > CONFIG_MEMCG. > > > > > > Neat. While you are at it wouldn't it make sesne to rename the function > > > as well. I do not want to bikeshed but this is really a misnomer. it > > > doesn't check anything about locking. page_belongs_lruvec? > > > > Right. lruvec_holds_page_lru_lock is used to check whether > > the page belongs to the lruvec. page_belongs_lruvec > > obviously more clearer. I can rename it to > > page_belongs_lruvec the next version. > > This sounds strange to me, I think 'belongs' needs a 'to' to be > correct, so page_belongs_to_lruvec(). Still kind of a mouthful. > > page_matches_lruvec()? > > page_from_lruvec()? Any of those is much better than what we have here.
On Thu, Apr 15, 2021 at 1:49 AM Johannes Weiner <hannes@cmpxchg.org> wrote: > > On Wed, Apr 14, 2021 at 06:00:42PM +0800, Muchun Song wrote: > > On Wed, Apr 14, 2021 at 5:44 PM Michal Hocko <mhocko@suse.com> wrote: > > > > > > On Tue 13-04-21 14:51:50, Muchun Song wrote: > > > > We already have a helper lruvec_memcg() to get the memcg from lruvec, we > > > > do not need to do it ourselves in the lruvec_holds_page_lru_lock(). So use > > > > lruvec_memcg() instead. And if mem_cgroup_disabled() returns false, the > > > > page_memcg(page) (the LRU pages) cannot be NULL. So remove the odd logic > > > > of "memcg = page_memcg(page) ? : root_mem_cgroup". And use lruvec_pgdat > > > > to simplify the code. We can have a single definition for this function > > > > that works for !CONFIG_MEMCG, CONFIG_MEMCG + mem_cgroup_disabled() and > > > > CONFIG_MEMCG. > > > > > > Neat. While you are at it wouldn't it make sesne to rename the function > > > as well. I do not want to bikeshed but this is really a misnomer. it > > > doesn't check anything about locking. page_belongs_lruvec? > > > > Right. lruvec_holds_page_lru_lock is used to check whether > > the page belongs to the lruvec. page_belongs_lruvec > > obviously more clearer. I can rename it to > > page_belongs_lruvec the next version. > > This sounds strange to me, I think 'belongs' needs a 'to' to be > correct, so page_belongs_to_lruvec(). Still kind of a mouthful. > > page_matches_lruvec()? > I prefer this name. If you also agree, I will use this name. Thanks. > page_from_lruvec()?
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 4f49865c9958..38b8d3fb24ff 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -755,22 +755,6 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page) return mem_cgroup_lruvec(memcg, pgdat); } -static inline bool lruvec_holds_page_lru_lock(struct page *page, - struct lruvec *lruvec) -{ - pg_data_t *pgdat = page_pgdat(page); - const struct mem_cgroup *memcg; - struct mem_cgroup_per_node *mz; - - if (mem_cgroup_disabled()) - return lruvec == &pgdat->__lruvec; - - mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec); - memcg = page_memcg(page) ? : root_mem_cgroup; - - return lruvec->pgdat == pgdat && mz->memcg == memcg; -} - struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p); struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm); @@ -1229,14 +1213,6 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page) return &pgdat->__lruvec; } -static inline bool lruvec_holds_page_lru_lock(struct page *page, - struct lruvec *lruvec) -{ - pg_data_t *pgdat = page_pgdat(page); - - return lruvec == &pgdat->__lruvec; -} - static inline void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page) { } @@ -1518,6 +1494,13 @@ 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) +{ + return lruvec_pgdat(lruvec) == page_pgdat(page) && + lruvec_memcg(lruvec) == page_memcg(page); +} + /* Don't lock again iff page's lruvec locked */ static inline struct lruvec *relock_page_lruvec_irq(struct page *page, struct lruvec *locked_lruvec)