[PATCH net-next 0/2] net/smc: transition to RDMA core CQ pooling

[D. Wythe]

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.

Link: https://lore.kernel.org/netdev/20260305022323.96125-1-alibuda@xxxxxxxxxxxxxxxxx/

---
Changes v1 -> v2:
https://lore.kernel.org/netdev/20260508063718.101622-1-alibuda@xxxxxxxxxxxxxxxxx/
1. remove unnecessary inline from static CQE init helpers.
2. Use ib_drain_qp() with +1 max_send_wr; 
3. Fix v2 state clearing.
4. Add re-check after schedule_timeout() to fix timeout/signal races.

D. Wythe (2):
  net/smc: transition to RDMA core CQ pooling
  net/smc: reduce TX slot contention with exclusive wait

 net/smc/smc_core.c |   9 +-
 net/smc/smc_core.h |  28 ++--
 net/smc/smc_ib.c   | 113 +++++----------
 net/smc/smc_ib.h   |   7 -
 net/smc/smc_tx.c   |   1 -
 net/smc/smc_wr.c   | 344 ++++++++++++++++++++-------------------------
 net/smc/smc_wr.h   |  40 ++----
 7 files changed, 215 insertions(+), 327 deletions(-)

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2.45.0