[PATCH net-next v4] rds: ib: Remove unused extern definition

From: Håkon Bugge
Date: Fri Sep 05 2025 - 06:22:32 EST


In the old days, RDS used FMR (Fast Memory Registration) to register
IB MRs to be used by RDMA. A newer and better verbs based
registration/de-registration method called FRWR (Fast Registration
Work Request) was added to RDS by commit 1659185fb4d0 ("RDS: IB:
Support Fastreg MR (FRMR) memory registration mode") in 2016.

Detection and enablement of FRWR was done in commit 2cb2912d6563
("RDS: IB: add Fastreg MR (FRMR) detection support"). But said commit
added an extern bool prefer_frmr, which was not used by said commit -
nor used by later commits. Hence, remove it.

Signed-off-by: Håkon Bugge <haakon.bugge@xxxxxxxxxx>
Reviewed-by: Allison Henderson <allison.henderson@xxxxxxxxxx>

---

v3 -> v4:
* Added Allison's r-b
* Removed indentation for this section

v2 -> v3:
* As per Jakub's request, removed Cc: and Fixes: tags
* Subject to net-next (instead of net)

v1 -> v2:
* Added commit message
* Added Cc: stable@xxxxxxxxxxxxxxx
---
net/rds/ib_mr.h | 1 -
1 file changed, 1 deletion(-)

diff --git a/net/rds/ib_mr.h b/net/rds/ib_mr.h
index ea5e9aee4959e..5884de8c6f45b 100644
--- a/net/rds/ib_mr.h
+++ b/net/rds/ib_mr.h
@@ -108,7 +108,6 @@ struct rds_ib_mr_pool {
};

extern struct workqueue_struct *rds_ib_mr_wq;
-extern bool prefer_frmr;

struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_dev,
int npages);
--
2.43.5