linux/drivers/infiniband
Shiraz Saleem 2df6d89590 RDMA/irdma: Reduce iWARP QP destroy time
QP destroy is synchronous and waits for its refcnt to be decremented in
irdma_cm_node_free_cb (for iWARP) which fires after the RCU grace period
elapses.

Applications running a large number of connections are exposed to high
wait times on destroy QP for events like SIGABORT.

The long pole for this wait time is the firing of the call_rcu callback
during a CM node destroy which can be slow. It holds the QP reference
count and blocks the destroy QP from completing.

call_rcu only needs to make sure that list walkers have a reference to the
cm_node object before freeing it and thus need to wait for grace period
elapse. The rest of the connection teardown in irdma_cm_node_free_cb is
moved out of the grace period wait in irdma_destroy_connection. Also,
replace call_rcu with a simple kfree_rcu as it just needs to do a kfree on
the cm_node

Fixes: 146b9756f1 ("RDMA/irdma: Add connection manager")
Link: https://lore.kernel.org/r/20220425181703.1634-3-shiraz.saleem@intel.com
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2022-05-02 11:10:33 -03:00
..
core IB/cm: Cancel mad on the DREQ event when the state is MRA_REP_RCVD 2022-04-04 10:32:02 -03:00
hw RDMA/irdma: Reduce iWARP QP destroy time 2022-05-02 11:10:33 -03:00
sw RDMA/rxe: Recheck the MR in when generating a READ reply 2022-04-20 11:21:24 -03:00
ulp SCSI misc on 20220324 2022-03-24 19:37:53 -07:00
Kconfig RDMA/irdma: Add irdma Kconfig/Makefile and remove i40iw 2021-06-02 20:06:36 -03:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00