On Tue, Jun 02, 2026 at 02:03:59PM -0700, Jakub Kicinski wrote:

On Thu, 28 May 2026 16:48:17 +0800 D. Wythe wrote:

quoted

This series transitions SMC-R completion handling to RDMA core CQ pooling
via the ib_cqe API. The new completion model improves scalability by
allowing per-link completion processing across multiple cores and enables
DIM-based interrupt moderation.

As a side effect, the increased concurrency can amplify contention for TX
slots on the shared wait queue. Patch 2 addresses this by switching TX slot
allocation from non-exclusive wait_event() to prepare_to_wait_exclusive(),
which avoids thundering-herd wakeups under contention.

Patch 1 replaces the global per-device CQ and manual tasklet polling model
with RDMA core CQ pooling.
Patch 2 reduces TX slot contention by using exclusive wait queue entries
during allocation.

Sashiko reports a couple of issues on patch 1:
https://sashiko.dev/#/patchset/20260528084819.6059-2-alibuda@linux.alibaba.com
Are these legit?

Either way - would be good to get some reviews here from (ohter) SMC
maintainers.

Thanks for the heads up. 

We’ve seen the Sashiko reports and are currently evaluating whether
they’re legit. So far it looks valid, though some of the issues may be
uncovering pre-existing problems. If needed, we may send extra patches
to fix them before applying this patch. The SMC maintainers are already
aware, and I expect more maintainers to join the review soon.

D. Wythe