On 08/12/2022 14:02, Tobias Burnus wrote:
On 08.12.22 13:51, Andrew Stubbs wrote:
On 08/12/2022 12:11, Jakub Jelinek wrote:
On Thu, Jul 07, 2022 at 11:34:33AM +0100, Andrew Stubbs wrote:
Implement the OpenMP pinned memory trait on Linux hosts using the mlock
syscall. Pinned allocations are performed using mmap, not malloc,
to ensure
that they can be unpinned safely when freed.
As I said before, I think the pinned memory is too precious to waste
it this
way, we should handle the -> pinned case through memkind_create_fixed on
mmap + mlock area, that way we can create even quite small pinned
allocations.
This has been delayed due to other priorities, but our current plan is
to switch to using cudaHostAlloc, when available, but we can certainly
use memkind_create_fixed for the fallback case (including amdgcn).
With available, I assume that nvptx is an 'available device' (per OpenMP
definition, finally added in TR11), i.e. there is an image for nvptx and
- after omp_requires filtering - there remains at least one nvptx device.
If plugin-nvptx has been loaded then the function will be available. Do
we need to get fancier than that?
Andrew
