lkml.org 
[lkml]   [2024]   [May]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC PATCH net-next v8 02/14] net: page_pool: create hooks for custom page providers
On Wed, May 08, 2024 at 12:35:52PM +0100, Pavel Begunkov wrote:
> > all these, because e.g. ttm internally does have a page pool because
> > depending upon allocator, that's indeed beneficial. Other drm drivers have
> > more buffer-based concepts for opportunistically memory around, usually
> > by marking buffers that are just kept as cache as purgeable (which is a
> > concept that goes all the way to opengl/vulkan).
>
> Because in this case it solves nothing and helps with nothing, quite
> the opposite. Just as well we can ask why NVMe doesn't wrap user pages
> into a dmabuf while doing IO.

You seem to confused totally unrelated things.

For short-term pins, that is pin_user_pages without FOLL_LONGTERM there
would never be any point in using a dmabuf as the pin is transient. For
long-term pin dmabufs in the block layer absolutely make sense, and I
wish io_uring would have just implemented them from the start instead of
the current fixed buffers that are not quite as useful by not
pre-mapping DMA and not supporting P2P.


\
 
 \ /
  Last update: 2024-05-08 17:52    [W:0.130 / U:1.204 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site