xprtrdma: Add trace points to instrument memory invalidation

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index cfa3c03..0e89e55 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -1349,6 +1349,7 @@ rpcrdma_mr_unmap_and_put(struct rpcrdma_mr *mr)
 {
 	struct rpcrdma_xprt *r_xprt = mr->mr_xprt;
 
+	trace_xprtrdma_dma_unmap(mr);
 	ib_dma_unmap_sg(r_xprt->rx_ia.ri_device,
 			mr->mr_sg, mr->mr_nents, mr->mr_dir);
 	__rpcrdma_mr_put(&r_xprt->rx_buf, mr);