RDMA/counters: Properly implement PID checks

"Auto" configuration mode is called for visible in that PID
namespace and it ensures that all counters and QPs are coexist
in the same namespace and belong to same PID.

Fixes: 99fa331d ("RDMA/counter: Add "auto" configuration mode support")
Reviewed-by: Mark Zhang <markz@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Link: https://lore.kernel.org/r/20190815083834.9245-3-leon@kernel.orgSigned-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/core/counters.c

@@ -149,13 +149,11 @@ static bool auto_mode_match(struct ib_qp *qp, struct rdma_counter *counter,
 	struct auto_mode_param *param = &counter->mode.param;
 	bool match = true;
 
-	if (rdma_is_kernel_res(&counter->res) != rdma_is_kernel_res(&qp->res))
+	if (!rdma_is_visible_in_pid_ns(&qp->res))
 		return false;
 
-	/* Ensure that counter belong to right PID */
-	if (!rdma_is_kernel_res(&counter->res) &&
-	    !rdma_is_kernel_res(&qp->res) &&
-	    (task_pid_vnr(counter->res.task) != current->pid))
+	/* Ensure that counter belongs to the right PID */
+	if (task_pid_nr(counter->res.task) != task_pid_nr(qp->res.task))
 		return false;
 
 	if (auto_mask & RDMA_COUNTER_MASK_QP_TYPE)