Re: [PATCH 13/16] mm/huge_memory: add helper __get_deferred_split_queue

[Miaohe Lin]

On 2022/6/23 15:03, Muchun Song wrote:
> On Thu, Jun 23, 2022 at 01:06:24AM +0800, Miaohe Lin wrote:
>> Add helper __get_deferred_split_queue to remove the duplicated codes of
>> getting ds_queue. No functional change intended.
>>
> 
> Sorry, I suggest dropping this change since I have reworked the code here [1].

That's all right. Thanks for your work. :)

> 
> [1] https://lore.kernel.org/all/20220621125658.64935-7-songmuchun@xxxxxxxxxxxxx/
> 
>> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
>> ---
>>  mm/huge_memory.c | 35 ++++++++++++-----------------------
>>  1 file changed, 12 insertions(+), 23 deletions(-)
>>
>> diff --git a/mm/huge_memory.c b/mm/huge_memory.c
>> index 0030b4f67cd9..de8155ff584c 100644
>> --- a/mm/huge_memory.c
>> +++ b/mm/huge_memory.c
>> @@ -555,25 +555,23 @@ pmd_t maybe_pmd_mkwrite(pmd_t pmd, struct vm_area_struct *vma)
>>  	return pmd;
>>  }
>>  
>> -#ifdef CONFIG_MEMCG
>> -static inline struct deferred_split *get_deferred_split_queue(struct page *page)
>> +static inline struct deferred_split *__get_deferred_split_queue(struct pglist_data *pgdat,
>> +								struct mem_cgroup *memcg)
>>  {
>> -	struct mem_cgroup *memcg = page_memcg(compound_head(page));
>> -	struct pglist_data *pgdat = NODE_DATA(page_to_nid(page));
>> -
>> +#ifdef CONFIG_MEMCG
>>  	if (memcg)
>>  		return &memcg->deferred_split_queue;
>> -	else
>> -		return &pgdat->deferred_split_queue;
>> +#endif
>> +	return &pgdat->deferred_split_queue;
>>  }
>> -#else
>> +
>>  static inline struct deferred_split *get_deferred_split_queue(struct page *page)
>>  {
>> +	struct mem_cgroup *memcg = page_memcg(compound_head(page));
>>  	struct pglist_data *pgdat = NODE_DATA(page_to_nid(page));
>>  
>> -	return &pgdat->deferred_split_queue;
>> +	return __get_deferred_split_queue(pgdat, memcg);
>>  }
>> -#endif
>>  
>>  void prep_transhuge_page(struct page *page)
>>  {
>> @@ -2774,31 +2772,22 @@ void deferred_split_huge_page(struct page *page)
>>  static unsigned long deferred_split_count(struct shrinker *shrink,
>>  		struct shrink_control *sc)
>>  {
>> -	struct pglist_data *pgdata = NODE_DATA(sc->nid);
>> -	struct deferred_split *ds_queue = &pgdata->deferred_split_queue;
>> +	struct deferred_split *ds_queue;
>>  
>> -#ifdef CONFIG_MEMCG
>> -	if (sc->memcg)
>> -		ds_queue = &sc->memcg->deferred_split_queue;
>> -#endif
>> +	ds_queue = __get_deferred_split_queue(NODE_DATA(sc->nid), sc->memcg);
>>  	return READ_ONCE(ds_queue->split_queue_len);
>>  }
>>  
>>  static unsigned long deferred_split_scan(struct shrinker *shrink,
>>  		struct shrink_control *sc)
>>  {
>> -	struct pglist_data *pgdata = NODE_DATA(sc->nid);
>> -	struct deferred_split *ds_queue = &pgdata->deferred_split_queue;
>> +	struct deferred_split *ds_queue;
>>  	unsigned long flags;
>>  	LIST_HEAD(list), *pos, *next;
>>  	struct page *page;
>>  	int split = 0;
>>  
>> -#ifdef CONFIG_MEMCG
>> -	if (sc->memcg)
>> -		ds_queue = &sc->memcg->deferred_split_queue;
>> -#endif
>> -
>> +	ds_queue = __get_deferred_split_queue(NODE_DATA(sc->nid), sc->memcg);
>>  	spin_lock_irqsave(&ds_queue->split_queue_lock, flags);
>>  	/* Take pin on all head pages to avoid freeing them under us */
>>  	list_for_each_safe(pos, next, &ds_queue->split_queue) {
>> -- 
>> 2.23.0
>>
>>
> .
>