Re: [PATCH] mm/slub: remove forced_order parameter in calculate_sizes

[Vlastimil Babka]

On 3/9/22 10:55, Hyeonggon Yoo wrote:
> On Wed, Mar 09, 2022 at 05:20:36PM +0800, Miaohe Lin wrote:
>> Since commit 32a6f409b693 ("mm, slub: remove runtime allocation order
>> changes"), forced_order is always -1. Remove this unneeded parameter
>> to simplify the code.
>> 
>> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
>> ---
>>  mm/slub.c | 11 ++++-------
>>  1 file changed, 4 insertions(+), 7 deletions(-)
>> 
>> diff --git a/mm/slub.c b/mm/slub.c
>> index 180354d7e741..7f09901ae6b2 100644
>> --- a/mm/slub.c
>> +++ b/mm/slub.c
>> @@ -4038,7 +4038,7 @@ static void set_cpu_partial(struct kmem_cache *s)
>>   * calculate_sizes() determines the order and the distribution of data within
>>   * a slab object.
>>   */
>> -static int calculate_sizes(struct kmem_cache *s, int forced_order)
>> +static int calculate_sizes(struct kmem_cache *s)
>>  {
>>  	slab_flags_t flags = s->flags;
>>  	unsigned int size = s->object_size;
>> @@ -4142,10 +4142,7 @@ static int calculate_sizes(struct kmem_cache *s, int forced_order)
>>  	size = ALIGN(size, s->align);
>>  	s->size = size;
>>  	s->reciprocal_size = reciprocal_value(size);
>> -	if (forced_order >= 0)
>> -		order = forced_order;
>> -	else
>> -		order = calculate_order(size);
>> +	order = calculate_order(size);
>>  
>>  	if ((int)order < 0)
>>  		return 0;
>> @@ -4181,7 +4178,7 @@ static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags)
>>  	s->random = get_random_long();
>>  #endif
>>  
>> -	if (!calculate_sizes(s, -1))
>> +	if (!calculate_sizes(s))
>>  		goto error;
>>  	if (disable_higher_order_debug) {
>>  		/*
>> @@ -4191,7 +4188,7 @@ static int kmem_cache_open(struct kmem_cache *s, slab_flags_t flags)
>>  		if (get_order(s->size) > get_order(s->object_size)) {
>>  			s->flags &= ~DEBUG_METADATA_FLAGS;
>>  			s->offset = 0;
>> -			if (!calculate_sizes(s, -1))
>> +			if (!calculate_sizes(s))
>>  				goto error;
>>  		}
>>  	}
> 
> Looks good to me.
> 
> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>

Thanks both, added to slab-next

> Thanks!
> 
>> -- 
>> 2.23.0
> 
> --
> Thank you, You are awesome!
> Hyeonggon :-)