Re: [PATCH v6 2/5] mm/mempolicy: export memory policy symbols

Vlastimil Babka
2025-02-26T13:57:48Z

On 2/26/25 9:25 AM, Shivank Garg wrote:
> KVM guest_memfd wants to implement support for NUMA policies just like
> shmem already does using the shared policy infrastructure. As
> guest_memfd currently resides in KVM module code, we have to export the
> relevant symbols.
>
> In the future, guest_memfd might be moved to core-mm, at which point the
> symbols no longer would have to be exported. When/if that happens is
> still unclear.
>
> Acked-by: David Hildenbrand <david@redhat.com>
> Signed-off-by: Shivank Garg <shivankg@amd.com>

Acked-by: Vlastimil Babka <vbabka@suse.cz>

> ---
> mm/mempolicy.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> index bbaadbeeb291..d9c5dcdadcd0 100644
> --- a/mm/mempolicy.c
> +++ b/mm/mempolicy.c
> @@ -214,6 +214,7 @@ struct mempolicy *get_task_policy(struct task_struct *p)
>
> return &default_policy;
> }
> +EXPORT_SYMBOL_GPL(get_task_policy);
>
> static const struct mempolicy_operations {
> int (*create)(struct mempolicy *pol, const nodemask_t *nodes);
> @@ -347,6 +348,7 @@ void __mpol_put(struct mempolicy *pol)
> return;
> kmem_cache_free(policy_cache, pol);
> }
> +EXPORT_SYMBOL_GPL(__mpol_put);
>
> static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes)
> {
> @@ -2736,6 +2738,7 @@ struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp,
> read_unlock(&sp->lock);
> return pol;
> }
> +EXPORT_SYMBOL_GPL(mpol_shared_policy_lookup);
>
> static void sp_free(struct sp_node *n)
> {
> @@ -3021,6 +3024,7 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
> mpol_put(mpol); /* drop our incoming ref on sb mpol */
> }
> }
> +EXPORT_SYMBOL_GPL(mpol_shared_policy_init);
>
> int mpol_set_shared_policy(struct shared_policy *sp,
> struct vm_area_struct *vma, struct mempolicy *pol)
> @@ -3039,6 +3043,7 @@ int mpol_set_shared_policy(struct shared_policy *sp,
> sp_free(new);
> return err;
> }
> +EXPORT_SYMBOL_GPL(mpol_set_shared_policy);
>
> /* Free a backing policy store on inode delete. */
> void mpol_free_shared_policy(struct shared_policy *sp)
> @@ -3057,6 +3062,7 @@ void mpol_free_shared_policy(struct shared_policy *sp)
> }
> write_unlock(&sp->lock);
> }
> +EXPORT_SYMBOL_GPL(mpol_free_shared_policy);
>
> #ifdef CONFIG_NUMA_BALANCING
> static int __initdata numabalancing_override;