Re: [PATCH] dma/pool: do not complain if DMA pool is not allocated

Christoph Hellwig
2022-08-11T08:21:42Z

On Thu, Aug 11, 2022 at 10:20:43AM +0200, Michal Hocko wrote:
> Meminfo part says
> Node 0 DMA free:160kB boost:0kB min:0kB low:0kB high:0kB reserved_highatomic:0KB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:15996kB managed:15360kB mlocked:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB
>
> So the zone has 15MB of managed memory (by the page allocator), yet only
> 160kB is free early boot during the allocation. So it is mostly consumed
> by somebody. I haven't really checked by whom.
>
> Does that exaplain the above better?

Yes. I'm really curious who eats up all the GFP_DMA memory early during
boot, though.