On Mon, 27 Jan 2020 18:59:57 -0800 Arjun Roy <arjunroy.kdev@xxxxxxxxx> wrote:
> Add the ability to insert multiple pages at once to a user VM with
> lower PTE spinlock operations.
>
> The intention of this patch-set is to reduce atomic ops for
> tcp zerocopy receives, which normally hits the same spinlock multiple
> times consecutively.
Seems sensible, thanks. Some other vm_insert_page() callers might want
to know about this, but I can't immediately spot any which appear to be
high bandwidth.
Is there much point in keeping the vm_insert_page() implementation
around? Replace it with
static inline int
vm_insert_page(struct vm_area_struct *vma, unsigned long addr,
struct page *page)
{
return vm_insert_pages(vma, addr, &page, 1);
}
?
Also, vm_insert_page() does
if (!page_count(page))
return -EINVAL;
and this was not carried over into vm_insert_pages(). How come?
I don't know what that test does - it was added by Linus in the
original commit a145dd411eb28c83. It's only been 15 years so I'm sure
he remembers ;)
