On Tue, Oct 21, 2014 at 04:21:33PM -0400, Johannes Weiner wrote: > The wrappers around taking and dropping the memcg->move_lock spinlock > add nothing of value. Inline the spinlock calls into the callsites. > > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Acked-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> > --- > mm/memcontrol.c | 34 +++++++++------------------------- > 1 file changed, 9 insertions(+), 25 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 293db8234179..1ff125d2a427 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1507,23 +1507,6 @@ static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg) > return false; > } > > -/* > - * Take this lock when > - * - a code tries to modify page's memcg while it's USED. > - * - a code tries to modify page state accounting in a memcg. > - */ > -static void move_lock_mem_cgroup(struct mem_cgroup *memcg, > - unsigned long *flags) > -{ > - spin_lock_irqsave(&memcg->move_lock, *flags); > -} > - > -static void move_unlock_mem_cgroup(struct mem_cgroup *memcg, > - unsigned long *flags) > -{ > - spin_unlock_irqrestore(&memcg->move_lock, *flags); > -} > - > #define K(x) ((x) << (PAGE_SHIFT-10)) > /** > * mem_cgroup_print_oom_info: Print OOM information relevant to memory controller. > @@ -2013,7 +1996,7 @@ again: > return; > /* > * If this memory cgroup is not under account moving, we don't > - * need to take move_lock_mem_cgroup(). Because we already hold > + * need to take &memcg->move_lock. Because we already hold > * rcu_read_lock(), any calls to move_account will be delayed until > * rcu_read_unlock(). > */ > @@ -2021,9 +2004,9 @@ again: > if (atomic_read(&memcg->moving_account) <= 0) > return; > > - move_lock_mem_cgroup(memcg, flags); > + spin_lock_irqsave(&memcg->move_lock, *flags); > if (memcg != pc->mem_cgroup) { > - move_unlock_mem_cgroup(memcg, flags); > + spin_unlock_irqrestore(&memcg->move_lock, *flags); > goto again; > } > *locked = true; > @@ -2038,7 +2021,7 @@ void __mem_cgroup_end_update_page_stat(struct page *page, unsigned long *flags) > * lock is held because a routine modifies pc->mem_cgroup > * should take move_lock_mem_cgroup(). > */ > - move_unlock_mem_cgroup(pc->mem_cgroup, flags); > + spin_unlock_irqrestore(&pc->mem_cgroup->move_lock, *flags); > } > > void mem_cgroup_update_page_stat(struct page *page, > @@ -3083,7 +3066,7 @@ static int mem_cgroup_move_account(struct page *page, > if (pc->mem_cgroup != from) > goto out_unlock; > > - move_lock_mem_cgroup(from, &flags); > + spin_lock_irqsave(&from->move_lock, flags); > > if (!PageAnon(page) && page_mapped(page)) { > __this_cpu_sub(from->stat->count[MEM_CGROUP_STAT_FILE_MAPPED], > @@ -3107,7 +3090,8 @@ static int mem_cgroup_move_account(struct page *page, > > /* caller should have done css_get */ > pc->mem_cgroup = to; > - move_unlock_mem_cgroup(from, &flags); > + spin_unlock_irqrestore(&from->move_lock, flags); > + > ret = 0; > > local_irq_disable(); > @@ -6033,9 +6017,9 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage, > * but there might still be references, e.g. from finishing > * writeback. Follow the charge moving protocol here. > */ > - move_lock_mem_cgroup(memcg, &flags); > + spin_lock_irqsave(&memcg->move_lock, flags); > pc->mem_cgroup = NULL; > - move_unlock_mem_cgroup(memcg, &flags); > + spin_unlock_irqrestore(&memcg->move_lock, flags); > > if (lrucare) > unlock_page_lru(oldpage, isolated); > -- > 2.1.2 > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>