On Wed 16-12-20 13:52:13, Hui Su wrote: > the rcu_read_lock and rcu_read_unlock is unnecessary in: > lock_page_lruvec() > lock_page_lruvec_irq() > lock_page_lruvec_irqsave() Please add an explanation why it is unnecessary. > Signed-off-by: Hui Su <sh_def@xxxxxxx> > --- > mm/memcontrol.c | 6 ------ > 1 file changed, 6 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index e3c7ca7dc174..a19f820e8a3f 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1396,10 +1396,8 @@ struct lruvec *lock_page_lruvec(struct page *page) > struct lruvec *lruvec; > struct pglist_data *pgdat = page_pgdat(page); > > - rcu_read_lock(); > lruvec = mem_cgroup_page_lruvec(page, pgdat); > spin_lock(&lruvec->lru_lock); > - rcu_read_unlock(); > > lruvec_memcg_debug(lruvec, page); > > @@ -1411,10 +1409,8 @@ struct lruvec *lock_page_lruvec_irq(struct page *page) > struct lruvec *lruvec; > struct pglist_data *pgdat = page_pgdat(page); > > - rcu_read_lock(); > lruvec = mem_cgroup_page_lruvec(page, pgdat); > spin_lock_irq(&lruvec->lru_lock); > - rcu_read_unlock(); > > lruvec_memcg_debug(lruvec, page); > > @@ -1426,10 +1422,8 @@ struct lruvec *lock_page_lruvec_irqsave(struct page *page, unsigned long *flags) > struct lruvec *lruvec; > struct pglist_data *pgdat = page_pgdat(page); > > - rcu_read_lock(); > lruvec = mem_cgroup_page_lruvec(page, pgdat); > spin_lock_irqsave(&lruvec->lru_lock, *flags); > - rcu_read_unlock(); > > lruvec_memcg_debug(lruvec, page); > > -- > 2.29.2 -- Michal Hocko SUSE Labs
