[PATCH v1 04/12] xprtrdma: Add trace points in the RPC Reply handler paths

[Chuck Lever <chuck.lever@oracle.com>]

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 include/trace/events/rpcrdma.h |  162 ++++++++++++++++++++++++++++++++++++++++
 net/sunrpc/xprtrdma/rpc_rdma.c |   17 +---
 net/sunrpc/xprtrdma/verbs.c    |   11 +--
 3 files changed, 171 insertions(+), 19 deletions(-)

diff --git a/include/trace/events/rpcrdma.h b/include/trace/events/rpcrdma.h
index 8efb2c9..e11bb32 100644
--- a/include/trace/events/rpcrdma.h
+++ b/include/trace/events/rpcrdma.h
@@ -11,6 +11,46 @@
 #include <trace/events/rdma.h>
 
 /**
+ ** Event classes
+ **/
+
+DECLARE_EVENT_CLASS(xprtrdma_reply_event,
+	TP_PROTO(
+		const struct rpcrdma_rep *rep
+	),
+
+	TP_ARGS(rep),
+
+	TP_STRUCT__entry(
+		__field(const void *, rep)
+		__field(const void *, r_xprt)
+		__field(u32, xid)
+		__field(u32, version)
+		__field(u32, proc)
+	),
+
+	TP_fast_assign(
+		__entry->rep = rep;
+		__entry->r_xprt = rep->rr_rxprt;
+		__entry->xid = be32_to_cpu(rep->rr_xid);
+		__entry->version = be32_to_cpu(rep->rr_vers);
+		__entry->proc = be32_to_cpu(rep->rr_proc);
+	),
+
+	TP_printk("rxprt %p xid=0x%08x rep=%p: version %u proc %u",
+		__entry->r_xprt, __entry->xid, __entry->rep,
+		__entry->version, __entry->proc
+	)
+);
+
+#define DEFINE_REPLY_EVENT(name)					\
+		DEFINE_EVENT(xprtrdma_reply_event, name,		\
+				TP_PROTO(				\
+					const struct rpcrdma_rep *rep	\
+				),					\
+				TP_ARGS(rep))
+
+/**
  ** Call events
  **/
 
@@ -101,6 +141,29 @@
 	)
 );
 
+TRACE_EVENT(xprtrdma_post_recv,
+	TP_PROTO(
+		const struct rpcrdma_rep *rep,
+		int status
+	),
+
+	TP_ARGS(rep, status),
+
+	TP_STRUCT__entry(
+		__field(const void *, rep)
+		__field(int, status)
+	),
+
+	TP_fast_assign(
+		__entry->rep = rep;
+		__entry->status = status;
+	),
+
+	TP_printk("rep=%p status=%d",
+		__entry->rep, __entry->status
+	)
+);
+
 /**
  ** Completion events
  **/
@@ -134,6 +197,105 @@
 	)
 );
 
+TRACE_EVENT(xprtrdma_wc_receive,
+	TP_PROTO(
+		const struct rpcrdma_rep *rep,
+		const struct ib_wc *wc
+	),
+
+	TP_ARGS(rep, wc),
+
+	TP_STRUCT__entry(
+		__field(const void *, rep)
+		__field(unsigned int, byte_len)
+		__field(unsigned int, status)
+		__field(unsigned int, vendor_err)
+	),
+
+	TP_fast_assign(
+		__entry->rep = rep;
+		__entry->byte_len = wc->byte_len;
+		__entry->status = wc->status;
+		__entry->vendor_err = __entry->status ? wc->vendor_err : 0;
+	),
+
+	TP_printk("rep=%p, %u bytes: %s (%u/0x%x)",
+		__entry->rep, __entry->byte_len,
+		rdma_show_wc_status(__entry->status),
+		__entry->status, __entry->vendor_err
+	)
+);
+
+/**
+ ** Reply events
+ **/
+
+TRACE_EVENT(xprtrdma_reply,
+	TP_PROTO(
+		const struct rpc_task *task,
+		const struct rpcrdma_rep *rep,
+		const struct rpcrdma_req *req,
+		unsigned int credits
+	),
+
+	TP_ARGS(task, rep, req, credits),
+
+	TP_STRUCT__entry(
+		__field(unsigned int, task_id)
+		__field(unsigned int, client_id)
+		__field(const void *, rep)
+		__field(const void *, req)
+		__field(u32, xid)
+		__field(unsigned int, credits)
+	),
+
+	TP_fast_assign(
+		__entry->task_id = task->tk_pid;
+		__entry->client_id = task->tk_client->cl_clid;
+		__entry->rep = rep;
+		__entry->req = req;
+		__entry->xid = be32_to_cpu(rep->rr_xid);
+		__entry->credits = credits;
+	),
+
+	TP_printk("task:%u@%u xid=0x%08x, %u credits, rep=%p -> req=%p",
+		__entry->task_id, __entry->client_id, __entry->xid,
+		__entry->credits, __entry->rep, __entry->req
+	)
+);
+
+TRACE_EVENT(xprtrdma_defer_cmp,
+	TP_PROTO(
+		const struct rpcrdma_rep *rep
+	),
+
+	TP_ARGS(rep),
+
+	TP_STRUCT__entry(
+		__field(unsigned int, task_id)
+		__field(unsigned int, client_id)
+		__field(const void *, rep)
+		__field(u32, xid)
+	),
+
+	TP_fast_assign(
+		__entry->task_id = rep->rr_rqst->rq_task->tk_pid;
+		__entry->client_id = rep->rr_rqst->rq_task->tk_client->cl_clid;
+		__entry->rep = rep;
+		__entry->xid = be32_to_cpu(rep->rr_xid);
+	),
+
+	TP_printk("task:%u@%u xid=0x%08x rep=%p",
+		__entry->task_id, __entry->client_id, __entry->xid,
+		__entry->rep
+	)
+);
+
+DEFINE_REPLY_EVENT(xprtrdma_reply_vers);
+DEFINE_REPLY_EVENT(xprtrdma_reply_rqst);
+DEFINE_REPLY_EVENT(xprtrdma_reply_short);
+DEFINE_REPLY_EVENT(xprtrdma_reply_hdr);
+
 #endif /* _TRACE_RPCRDMA_H */
 
 #include <trace/define_trace.h>
diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index 162c0fd..6f774f1e4 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -1278,8 +1278,7 @@ void rpcrdma_complete_rqst(struct rpcrdma_rep *rep)
  * being marshaled.
  */
 out_badheader:
-	dprintk("RPC: %5u %s: invalid rpcrdma reply (type %u)\n",
-		rqst->rq_task->tk_pid, __func__, be32_to_cpu(rep->rr_proc));
+	trace_xprtrdma_reply_hdr(rep);
 	r_xprt->rx_stats.bad_reply_count++;
 	status = -EIO;
 	goto out;
@@ -1323,6 +1322,7 @@ void rpcrdma_deferred_completion(struct work_struct *work)
 	struct rpcrdma_req *req = rpcr_to_rdmar(rep->rr_rqst);
 	struct rpcrdma_xprt *r_xprt = rep->rr_rxprt;
 
+	trace_xprtrdma_defer_cmp(rep);
 	if (rep->rr_wc_flags & IB_WC_WITH_INVALIDATE)
 		r_xprt->rx_ia.ri_ops->ro_reminv(rep, &req->rl_registered);
 	rpcrdma_release_rqst(r_xprt, req);
@@ -1344,8 +1344,6 @@ void rpcrdma_reply_handler(struct rpcrdma_rep *rep)
 	u32 credits;
 	__be32 *p;
 
-	dprintk("RPC:       %s: incoming rep %p\n", __func__, rep);
-
 	if (rep->rr_hdrbuf.head[0].iov_len == 0)
 		goto out_badstatus;
 
@@ -1389,8 +1387,7 @@ void rpcrdma_reply_handler(struct rpcrdma_rep *rep)
 	rep->rr_rqst = rqst;
 	clear_bit(RPCRDMA_REQ_F_PENDING, &req->rl_flags);
 
-	dprintk("RPC:       %s: reply %p completes request %p (xid 0x%08x)\n",
-		__func__, rep, req, be32_to_cpu(rep->rr_xid));
+	trace_xprtrdma_reply(rqst->rq_task, rep, req, credits);
 
 	queue_work_on(req->rl_cpu, rpcrdma_receive_wq, &rep->rr_work);
 	return;
@@ -1404,8 +1401,7 @@ void rpcrdma_reply_handler(struct rpcrdma_rep *rep)
 	return;
 
 out_badversion:
-	dprintk("RPC:       %s: invalid version %d\n",
-		__func__, be32_to_cpu(rep->rr_vers));
+	trace_xprtrdma_reply_vers(rep);
 	goto repost;
 
 /* The RPC transaction has already been terminated, or the header
@@ -1413,12 +1409,11 @@ void rpcrdma_reply_handler(struct rpcrdma_rep *rep)
  */
 out_norqst:
 	spin_unlock(&xprt->recv_lock);
-	dprintk("RPC:       %s: no match for incoming xid 0x%08x\n",
-		__func__, be32_to_cpu(rep->rr_xid));
+	trace_xprtrdma_reply_rqst(rep);
 	goto repost;
 
 out_shortreply:
-	dprintk("RPC:       %s: short/invalid reply\n", __func__);
+	trace_xprtrdma_reply_short(rep);
 
 /* If no pending RPC transaction was matched, post a replacement
  * receive buffer before returning.
diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
index 06d86b8..cfa3c03 100644
--- a/net/sunrpc/xprtrdma/verbs.c
+++ b/net/sunrpc/xprtrdma/verbs.c
@@ -156,13 +156,11 @@
 					       rr_cqe);
 
 	/* WARNING: Only wr_id and status are reliable at this point */
+	trace_xprtrdma_wc_receive(rep, wc);
 	if (wc->status != IB_WC_SUCCESS)
 		goto out_fail;
 
 	/* status == SUCCESS means all fields in wc are trustworthy */
-	dprintk("RPC:       %s: rep %p opcode 'recv', length %u: success\n",
-		__func__, rep, wc->byte_len);
-
 	rpcrdma_set_xdrlen(&rep->rr_hdrbuf, wc->byte_len);
 	rep->rr_wc_flags = wc->wc_flags;
 	rep->rr_inv_rkey = wc->ex.invalidate_rkey;
@@ -1576,17 +1574,14 @@ struct rpcrdma_regbuf *
 	if (!rpcrdma_dma_map_regbuf(ia, rep->rr_rdmabuf))
 		goto out_map;
 	rc = ib_post_recv(ia->ri_id->qp, &rep->rr_recv_wr, &recv_wr_fail);
+	trace_xprtrdma_post_recv(rep, rc);
 	if (rc)
-		goto out_postrecv;
+		return -ENOTCONN;
 	return 0;
 
 out_map:
 	pr_err("rpcrdma: failed to DMA map the Receive buffer\n");
 	return -EIO;
-
-out_postrecv:
-	pr_err("rpcrdma: ib_post_recv returned %i\n", rc);
-	return -ENOTCONN;
 }
 
 /**