SUNRPC: Hoist trace_xprtrdma_op_allocate into generic code

Introduce a tracepoint in call_allocate that reports the exact
sizes in the RPC buffer allocation request and the status of the
result. This helps catch problems with XDR buffer provisioning,
and replaces transport-specific debugging instrumentation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

include/trace/events/rpcrdma.h

@@ -1191,36 +1191,6 @@ TRACE_EVENT(xprtrdma_decode_seg,
  ** Allocation/release of rpcrdma_reqs and rpcrdma_reps
  **/
 
-TRACE_EVENT(xprtrdma_op_allocate,
-	TP_PROTO(
-		const struct rpc_task *task,
-		const struct rpcrdma_req *req
-	),
-
-	TP_ARGS(task, req),
-
-	TP_STRUCT__entry(
-		__field(unsigned int, task_id)
-		__field(unsigned int, client_id)
-		__field(const void *, req)
-		__field(size_t, callsize)
-		__field(size_t, rcvsize)
-	),
-
-	TP_fast_assign(
-		__entry->task_id = task->tk_pid;
-		__entry->client_id = task->tk_client->cl_clid;
-		__entry->req = req;
-		__entry->callsize = task->tk_rqstp->rq_callsize;
-		__entry->rcvsize = task->tk_rqstp->rq_rcvsize;
-	),
-
-	TP_printk("task:%u@%u req=%p (%zu, %zu)",
-		__entry->task_id, __entry->client_id,
-		__entry->req, __entry->callsize, __entry->rcvsize
-	)
-);
-
 TRACE_EVENT(xprtrdma_op_free,
 	TP_PROTO(
 		const struct rpc_task *task,

include/trace/events/sunrpc.h

@@ -517,6 +517,36 @@ DEFINE_RPC_REPLY_EVENT(stale_creds);
 DEFINE_RPC_REPLY_EVENT(bad_creds);
 DEFINE_RPC_REPLY_EVENT(auth_tooweak);
 
+TRACE_EVENT(rpc_buf_alloc,
+	TP_PROTO(
+		const struct rpc_task *task,
+		int status
+	),
+
+	TP_ARGS(task, status),
+
+	TP_STRUCT__entry(
+		__field(unsigned int, task_id)
+		__field(unsigned int, client_id)
+		__field(size_t, callsize)
+		__field(size_t, recvsize)
+		__field(int, status)
+	),
+
+	TP_fast_assign(
+		__entry->task_id = task->tk_pid;
+		__entry->client_id = task->tk_client->cl_clid;
+		__entry->callsize = task->tk_rqstp->rq_callsize;
+		__entry->recvsize = task->tk_rqstp->rq_rcvsize;
+		__entry->status = status;
+	),
+
+	TP_printk("task:%u@%u callsize=%zu recvsize=%zu status=%d",
+		__entry->task_id, __entry->client_id,
+		__entry->callsize, __entry->recvsize, __entry->status
+	)
+);
+
 TRACE_EVENT(rpc_call_rpcerror,
 	TP_PROTO(
 		const struct rpc_task *task,

net/sunrpc/clnt.c

@@ -1823,6 +1823,7 @@ call_allocate(struct rpc_task *task)
 	req->rq_rcvsize <<= 2;
 
 	status = xprt->ops->buf_alloc(task);
+	trace_rpc_buf_alloc(task, status);
 	xprt_inject_disconnect(xprt);
 	if (status == 0)
 		return;
@@ -1831,8 +1832,6 @@ call_allocate(struct rpc_task *task)
 		return;
 	}
 
-	dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
-
 	if (RPC_IS_ASYNC(task) || !fatal_signal_pending(current)) {
 		task->tk_action = call_allocate;
 		rpc_delay(task, HZ>>4);

net/sunrpc/sched.c

@@ -1036,8 +1036,6 @@ int rpc_malloc(struct rpc_task *task)
 		return -ENOMEM;
 
 	buf->len = size;
-	dprintk("RPC: %5u allocated buffer of size %zu at %p\n",
-			task->tk_pid, size, buf);
 	rqst->rq_buffer = buf->data;
 	rqst->rq_rbuffer = (char *)rqst->rq_buffer + rqst->rq_callsize;
 	return 0;

net/sunrpc/xprtrdma/transport.c

@@ -586,11 +586,9 @@ xprt_rdma_allocate(struct rpc_task *task)
 
 	rqst->rq_buffer = rdmab_data(req->rl_sendbuf);
 	rqst->rq_rbuffer = rdmab_data(req->rl_recvbuf);
-	trace_xprtrdma_op_allocate(task, req);
 	return 0;
 
 out_fail:
-	trace_xprtrdma_op_allocate(task, NULL);
 	return -ENOMEM;
 }