Re: malloc() size in CMA region seems to be aligned to CMA_ALIGNMENT

[Michal Hocko]

[CC linux-mm and some usual suspects]

On Tue 17-05-16 23:37:55, lunar12 lunartwix wrote:
> A 4MB dma_alloc_coherent  in kernel after malloc(2*1024) 40 times in
> CMA region by user space will cause an error on our ARM 3.18 kernel
> platform with a 32MB CMA.
> 
> It seems that the malloc in CMA region will be aligned to
> CMA_ALIGNMENT everytime even if the requested malloc size is very
> small so the CMA region is not available after the malloc operations.
> 
> Is there any configuraiton that can change this behavior??
> 
> Thanks
> 
> Cheers
> Ken

-- 
Michal Hocko
SUSE Labs