Re: [PATCH v3 2/4] hugetlb: Fix hugepages_setup when deal with pernode

From: David Hildenbrand
Date: Fri Apr 29 2022 - 05:30:47 EST


On 13.04.22 05:29, Peng Liu wrote:
> Hugepages can be specified to pernode since "hugetlbfs: extend
> the definition of hugepages parameter to support node allocation",
> but the following problem is observed.
>
> Confusing behavior is observed when both 1G and 2M hugepage is set
> after "numa=off".
> cmdline hugepage settings:
> hugepagesz=1G hugepages=0:3,1:3
> hugepagesz=2M hugepages=0:1024,1:1024
> results:
> HugeTLB registered 1.00 GiB page size, pre-allocated 0 pages
> HugeTLB registered 2.00 MiB page size, pre-allocated 1024 pages
>
> Furthermore, confusing behavior can be also observed when an
> invalid node behind a valid node. To fix this, never allocate any
> typical hugepage when an invalid parameter is received.
>
> Fixes: b5389086ad7b ("hugetlbfs: extend the definition of hugepages parameter to support node allocation")
> Signed-off-by: Peng Liu <liupeng256@xxxxxxxxxx>
> ---
> mm/hugetlb.c | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 5b5a2a5a742f..1930b6341f7e 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -4116,6 +4116,20 @@ bool __init __weak hugetlb_node_alloc_supported(void)
> {
> return true;
> }
> +
> +static void __init hugepages_clear_pages_in_node(void)

I think the name is a bit imprecise, but I have no better suggestion
right now.

Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>


--
Thanks,

David / dhildenb