Re: [PATCH 0/1] mm: restore full accuracy in COW page reuse

[Jason Gunthorpe]

On Sun, Jan 10, 2021 at 11:26:57PM -0800, John Hubbard wrote:

> So:
> 
> FOLL_PIN: would use DMA_PIN_COUNTING_BIAS to increment page refcount.
> These are long term pins for dma.
> 
> FOLL_GET: would use GUP_PIN_COUNTING_BIAS to increment page refcount.
> These are not long term pins.

Do we have any places yet that care about the long-term-ness?

The only place long term would matter is if something is waiting for
the page ref count to drop.

Jason