Re: [PATCH v2 1/3] mm: vmalloc: Let user to control huge vmalloc default behavior

From: Matthew Wilcox
Date: Wed Jan 19 2022 - 08:22:25 EST


On Wed, Jan 19, 2022 at 08:57:58PM +0800, Kefeng Wang wrote:
> Only parts of our products wants this feature,  we add some interfaces which
> only
>
> alloc hugevmalloc for them, eg,
> vmap_hugepage/vmalloc_hugepage/remap_vmalloc_hugepage_range..
>
> for our products, but it's not the choice of most products, also add
> nohugevmalloc
>
> for most products is expensive, so this is the reason for adding the patch.
>
> more config/cmdline are more flexible for test/products,

But why do only some products want it? What goes wrong if all products
enable it? Features should be auto-tuning, not relying on admins to
understand them.