Re: [PATCH for-next v2 0/2] RDMA/rxe: Prefetching pages with explicit ODP

[Daisuke Matsuda]

On 2025/05/04 2:08, Zhu Yanjun wrote:
> 在 2025/5/3 15:42, Daisuke Matsuda 写道:
> > There is ibv_advise_mr(3) that can be used by applications to optimize
> > memory access. This series enables the feature on rxe driver, which has
> > already been available in mlx5.
> >
> > There is a tiny change on the rdma-core util.
> > cf. https://github.com/linux-rdma/rdma-core/pull/1605
>
> Hi, Daisuke
>
> Thanks a lot for your efforts to this patch series. It is very nice. With this patch series, we can make prefetch for ODP MRs of RXE.
>
> I read through this patch series. And it seems fine with me.^_^
>
> IIRC, you have added ODP testcases in rdma-core. To verify this prefetch work well for ODP MRs, can you add this synchronous/asynchronous prefetch to the ODP testcases in rdma-core?
>
> Thus, we can verify this patch series. And in the future, we can use these testcases to confirm this prefetch feature work well.
>
> To now, it seems that no tool can verify this prefetch feature.

Hi, Thank you for taking a look!

There are already relevant testcases implemented in ./tests/test_odp.py:
 - test_odp_sync_prefetch_rc_traffic
 - test_odp_async_prefetch_rc_traffic
 - test_odp_prefetch_sync_no_page_fault_rc_traffic
 - test_odp_prefetch_async_no_page_fault_rc_traffic
On my node (x86-64/linux-6.15.0-rc1+), this series can pass all these tests.

Other than that, this feature is required by librpma as far as I know.
Though it is not maintained anymore, perhaps this could also be used for testing.
cf. https://github.com/pmem/rpma

Thanks,
Daisuke

> Thanks a lot.
> Zhu Yanjun
>
> > Daisuke Matsuda (2):
> >    RDMA/rxe: Implement synchronous prefetch for ODP MRs
> >    RDMA/rxe: Enable asynchronous prefetch for ODP MRs
> >
> >   drivers/infiniband/sw/rxe/rxe.c     |   7 ++
> >   drivers/infiniband/sw/rxe/rxe_loc.h |  10 ++
> >   drivers/infiniband/sw/rxe/rxe_odp.c | 165 ++++++++++++++++++++++++++++
> >   3 files changed, 182 insertions(+)