memcg: remove PCG_MOVE_LOCK flag from page_cgroup (312734c0) · Commits · e / devices / android_kernel_xiaomi_markw

include/linux/page_cgroup.h

+0 −19

Original line number	Original line	Diff line number	Diff line
	@@ -7,7 +7,6 @@ enum {
	PCG_USED, /* this object is in use. */		PCG_USED, /* this object is in use. */
	PCG_MIGRATION, /* under page migration */		PCG_MIGRATION, /* under page migration */
	/* flags for mem_cgroup and file and I/O status */		/* flags for mem_cgroup and file and I/O status */
	PCG_MOVE_LOCK, /* For race between move_account v.s. following bits */
	PCG_FILE_MAPPED, /* page is accounted as "mapped" */		PCG_FILE_MAPPED, /* page is accounted as "mapped" */
	__NR_PCG_FLAGS,		__NR_PCG_FLAGS,
	};		};
	@@ -89,24 +88,6 @@ static inline void unlock_page_cgroup(struct page_cgroup *pc)
	bit_spin_unlock(PCG_LOCK, &pc->flags);		bit_spin_unlock(PCG_LOCK, &pc->flags);
	}		}

	static inline void move_lock_page_cgroup(struct page_cgroup *pc,
	unsigned long *flags)
	{
	/*
	* We know updates to pc->flags of page cache's stats are from both of
	* usual context or IRQ context. Disable IRQ to avoid deadlock.
	*/
	local_irq_save(*flags);
	bit_spin_lock(PCG_MOVE_LOCK, &pc->flags);
	}

	static inline void move_unlock_page_cgroup(struct page_cgroup *pc,
	unsigned long *flags)
	{
	bit_spin_unlock(PCG_MOVE_LOCK, &pc->flags);
	local_irq_restore(*flags);
	}

	#else /* CONFIG_CGROUP_MEM_RES_CTLR */		#else /* CONFIG_CGROUP_MEM_RES_CTLR */
	struct page_cgroup;		struct page_cgroup;

mm/memcontrol.c

+32 −10

Original line number	Original line	Diff line number	Diff line
	@@ -300,6 +300,8 @@ struct mem_cgroup {
	* set > 0 if pages under this cgroup are moving to other cgroup.		* set > 0 if pages under this cgroup are moving to other cgroup.
	*/		*/
	atomic_t moving_account;		atomic_t moving_account;
			/* taken only while moving_account > 0 */
			spinlock_t move_lock;
	/*		/*
	* percpu counter.		* percpu counter.
	*/		*/
	@@ -1376,6 +1378,24 @@ static bool mem_cgroup_wait_acct_move(struct mem_cgroup *memcg)
	return false;		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.
			* see mem_cgroup_stealed(), too.
			*/
			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);
			}

	/**		/**
	* mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode.		* mem_cgroup_print_oom_info: Called from OOM with tasklist_lock held in read mode.
	* @memcg: The memory cgroup that went over limit		* @memcg: The memory cgroup that went over limit
	@@ -1900,7 +1920,7 @@ void mem_cgroup_update_page_stat(struct page *page,

	if (mem_cgroup_disabled())		if (mem_cgroup_disabled())
	return;		return;
			again:
	rcu_read_lock();		rcu_read_lock();
	memcg = pc->mem_cgroup;		memcg = pc->mem_cgroup;
	if (unlikely(!memcg \|\| !PageCgroupUsed(pc)))		if (unlikely(!memcg \|\| !PageCgroupUsed(pc)))
	@@ -1908,11 +1928,13 @@ void mem_cgroup_update_page_stat(struct page *page,
	/* pc->mem_cgroup is unstable ? */		/* pc->mem_cgroup is unstable ? */
	if (unlikely(mem_cgroup_stealed(memcg))) {		if (unlikely(mem_cgroup_stealed(memcg))) {
	/* take a lock against to access pc->mem_cgroup */		/* take a lock against to access pc->mem_cgroup */
	move_lock_page_cgroup(pc, &flags);		move_lock_mem_cgroup(memcg, &flags);
			if (memcg != pc->mem_cgroup \|\| !PageCgroupUsed(pc)) {
			move_unlock_mem_cgroup(memcg, &flags);
			rcu_read_unlock();
			goto again;
			}
	need_unlock = true;		need_unlock = true;
	memcg = pc->mem_cgroup;
	if (!memcg \|\| !PageCgroupUsed(pc))
	goto out;
	}		}

	switch (idx) {		switch (idx) {
	@@ -1931,7 +1953,7 @@ void mem_cgroup_update_page_stat(struct page *page,

	out:		out:
	if (unlikely(need_unlock))		if (unlikely(need_unlock))
	move_unlock_page_cgroup(pc, &flags);		move_unlock_mem_cgroup(memcg, &flags);
	rcu_read_unlock();		rcu_read_unlock();
	}		}

	@@ -2500,8 +2522,7 @@ static void __mem_cgroup_commit_charge(struct mem_cgroup *memcg,

	#ifdef CONFIG_TRANSPARENT_HUGEPAGE		#ifdef CONFIG_TRANSPARENT_HUGEPAGE

	#define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) \| (1 << PCG_MOVE_LOCK) \|\		#define PCGF_NOCOPY_AT_SPLIT ((1 << PCG_LOCK) \| (1 << PCG_MIGRATION))
	(1 << PCG_MIGRATION))
	/*		/*
	* Because tail pages are not marked as "used", set it. We're under		* Because tail pages are not marked as "used", set it. We're under
	* zone->lru_lock, 'splitting on pmd' and compound_lock.		* zone->lru_lock, 'splitting on pmd' and compound_lock.
	@@ -2572,7 +2593,7 @@ static int mem_cgroup_move_account(struct page *page,
	if (!PageCgroupUsed(pc) \|\| pc->mem_cgroup != from)		if (!PageCgroupUsed(pc) \|\| pc->mem_cgroup != from)
	goto unlock;		goto unlock;

	move_lock_page_cgroup(pc, &flags);		move_lock_mem_cgroup(from, &flags);

	if (PageCgroupFileMapped(pc)) {		if (PageCgroupFileMapped(pc)) {
	/* Update mapped_file data for mem_cgroup */		/* Update mapped_file data for mem_cgroup */
	@@ -2596,7 +2617,7 @@ static int mem_cgroup_move_account(struct page *page,
	* guaranteed that "to" is never removed. So, we don't check rmdir		* guaranteed that "to" is never removed. So, we don't check rmdir
	* status here.		* status here.
	*/		*/
	move_unlock_page_cgroup(pc, &flags);		move_unlock_mem_cgroup(from, &flags);
	ret = 0;		ret = 0;
	unlock:		unlock:
	unlock_page_cgroup(pc);		unlock_page_cgroup(pc);
	@@ -4971,6 +4992,7 @@ mem_cgroup_create(struct cgroup *cont)
	atomic_set(&memcg->refcnt, 1);		atomic_set(&memcg->refcnt, 1);
	memcg->move_charge_at_immigrate = 0;		memcg->move_charge_at_immigrate = 0;
	mutex_init(&memcg->thresholds_lock);		mutex_init(&memcg->thresholds_lock);
			spin_lock_init(&memcg->move_lock);
	return &memcg->css;		return &memcg->css;
	free_out:		free_out:
	__mem_cgroup_free(memcg);		__mem_cgroup_free(memcg);