SUNRPC: Fix backchannel latency metrics

commit 8729aaba74626c4ebce3abf1b9e96bb62d2958ca upstream.

I noticed that for callback requests, the reported backlog latency
is always zero, and the rtt value is crazy big. The problem was that
rqst->rq_xtime is never set for backchannel requests.

Fixes: 78215759e20d ("SUNRPC: Make RTT measurement more ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
index d1fcc41..908e78b 100644 (file)
--- a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
@@ -195,6 +195,7 @@ rpcrdma_bc_send_request(struct svcxprt_rdma *rdma, struct rpc_rqst *rqst)
        pr_info("%s: %*ph\n", __func__, 64, rqst->rq_buffer);
 #endif
 
+       rqst->rq_xtime = ktime_get();
        rc = svc_rdma_bc_sendto(rdma, rqst, ctxt);
        if (rc) {
                svc_rdma_send_ctxt_put(rdma, ctxt);

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 70e52f5..5361b98 100644 (file)
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -2659,6 +2659,8 @@ static int bc_sendto(struct rpc_rqst *req)
                .iov_len        = sizeof(marker),
        };
 
+       req->rq_xtime = ktime_get();
+
        len = kernel_sendmsg(transport->sock, &msg, &iov, 1, iov.iov_len);
        if (len != iov.iov_len)
                return -EAGAIN;
@@ -2684,7 +2686,6 @@ static int bc_send_request(struct rpc_rqst *req)
        struct svc_xprt *xprt;
        int len;
 
-       dprintk("sending request with xid: %08x\n", ntohl(req->rq_xid));
        /*
         * Get the server socket associated with this callback xprt
         */