Re: [PATCH v4 03/13] mm/vmemmap: Improve vmemmap_can_optimize and allow architectures to override

Christophe Leroy [off-list ref] writes:

Le 10/07/2023 à 18:08, Aneesh Kumar K.V a écrit :

quoted

dax vmemmap optimization requires a minimum of 2 PAGE_SIZE area within
vmemmap such that tail page mapping can point to the second PAGE_SIZE area.
Enforce that in vmemmap_can_optimize() function.

Architectures like powerpc also want to enable vmemmap optimization
conditionally (only with radix MMU translation). Hence allow architecture
override.

Signed-off-by: Aneesh Kumar K.V <redacted>

Reviewed-by: Christophe Leroy <redacted>

Why renaming vmemmap_can_optimize() to __vmemmap_can_optimize() and keep 
it when vmemmap_can_optimize() has been override ? Is that because you 
expect overriding version of vmemmap_can_optimize() to call 
__vmemmap_can_optimize() ?

Yes, __vmemap_can_optimize will be used in patch 11
https://lore.kernel.org/linuxppc-dev/20230710160842.56300-12-aneesh.kumar@linux.ibm.com (local)

-aneesh