Re: [PATCH] null_blk: Use bitmap_zalloc() when applicable

[Damien Le Moal]

On 1/6/22 16:44, Dan Carpenter wrote:
> On Thu, Dec 30, 2021 at 11:28:28AM +0900, Damien Le Moal wrote:
>>>  
>>> -	tag_size = ALIGN(nq->queue_depth, BITS_PER_LONG) / BITS_PER_LONG;
>>> -	nq->tag_map = kcalloc(tag_size, sizeof(unsigned long), GFP_KERNEL);
>>> +	nq->tag_map = bitmap_zalloc(nq->queue_depth, GFP_KERNEL);
>>>  	if (!nq->tag_map) {
>>>  		kfree(nq->cmds);
>>>  		return -ENOMEM;
>>
>> Before this patch, tag_size would always be a multiple of BITS_PER_LONG.
>> Using bitmap_zalloc(), that alignment goes away, but I think this is OK.
>>
> 
> It's still going to be a multiple of long.  Bitmaps are always stored
> in longs.

Yes, I understand that. I was referring to tag_size, which was rounded
before. But tag_size is only a local variable and not the actual queue
depth, which is not rounded. I got confused :)

> 
> regards,
> dan carpenter
> 


-- 
Damien Le Moal
Western Digital Research