On Wed, Jan 03, 2018 at 01:39:27PM -0600, Christopher Lameter wrote:
> +/* How many objects left in slab page */
> +unsigned kobjects_left_in_slab_page(const void *object)
> +{
> + struct page *page;
> +
> + if (unlikely(ZERO_OR_NULL_PTR(object)))
> + return 0;
> +
> + page = virt_to_head_page(object);
> +
> + if (unlikely(!PageSlab(page))) {
> + WARN_ON(1);
> + return 1;
> + }
I see this construct all over the kernel. Here's a better one:
if (WARN_ON(!PageSlab(page)))
return 1;
There's a built-in unlikely() in the definition of WARN_ON, so this
works nicely.
