net: tracepoint napi:napi_poll add work and budget

An important information for the napi_poll tracepoint is knowing
the work done (packets processed) by the napi_poll() call. Add
both the work done and budget, as they are related.

Handle trace_napi_poll() param change in dropwatch/drop_monitor
and in python perf script netdev-times.py in backward compat way,
as python fortunately supports optional parameter handling.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/trace/events/napi.h

@@ -12,22 +12,27 @@
 
 TRACE_EVENT(napi_poll,
 
-	TP_PROTO(struct napi_struct *napi),
+	TP_PROTO(struct napi_struct *napi, int work, int budget),
 
-	TP_ARGS(napi),
+	TP_ARGS(napi, work, budget),
 
 	TP_STRUCT__entry(
 		__field(	struct napi_struct *,	napi)
+		__field(	int,			work)
+		__field(	int,			budget)
 		__string(	dev_name, napi->dev ? napi->dev->name : NO_DEV)
 	),
 
 	TP_fast_assign(
 		__entry->napi = napi;
+		__entry->work = work;
+		__entry->budget = budget;
 		__assign_str(dev_name, napi->dev ? napi->dev->name : NO_DEV);
 	),
 
-	TP_printk("napi poll on napi struct %p for device %s",
-		__entry->napi, __get_str(dev_name))
+	TP_printk("napi poll on napi struct %p for device %s work %d budget %d",
+		  __entry->napi, __get_str(dev_name),
+		  __entry->work, __entry->budget)
 );
 
 #undef NO_DEV

net/core/dev.c

@@ -4972,7 +4972,7 @@ bool sk_busy_loop(struct sock *sk, int nonblock)
 
 			if (test_bit(NAPI_STATE_SCHED, &napi->state)) {
 				rc = napi->poll(napi, BUSY_POLL_BUDGET);
-				trace_napi_poll(napi);
+				trace_napi_poll(napi, rc, BUSY_POLL_BUDGET);
 				if (rc == BUSY_POLL_BUDGET) {
 					napi_complete_done(napi, rc);
 					napi_schedule(napi);
@@ -5128,7 +5128,7 @@ static int napi_poll(struct napi_struct *n, struct list_head *repoll)
 	work = 0;
 	if (test_bit(NAPI_STATE_SCHED, &n->state)) {
 		work = n->poll(n, weight);
-		trace_napi_poll(n);
+		trace_napi_poll(n, work, weight);
 	}
 
 	WARN_ON_ONCE(work > weight);

net/core/drop_monitor.c

@@ -187,7 +187,8 @@ static void trace_kfree_skb_hit(void *ignore, struct sk_buff *skb, void *locatio
 	trace_drop_common(skb, location);
 }
 
-static void trace_napi_poll_hit(void *ignore, struct napi_struct *napi)
+static void trace_napi_poll_hit(void *ignore, struct napi_struct *napi,
+				int work, int budget)
 {
 	struct dm_hw_stat_delta *new_stat;
 

net/core/netpoll.c

@@ -163,7 +163,7 @@ static void poll_one_napi(struct napi_struct *napi)
 	 */
 	work = napi->poll(napi, 0);
 	WARN_ONCE(work, "%pF exceeded budget in poll\n", napi->poll);
-	trace_napi_poll(napi);
+	trace_napi_poll(napi, work, 0);
 
 	clear_bit(NAPI_STATE_NPSVC, &napi->state);
 }

tools/perf/scripts/python/netdev-times.py

@@ -252,9 +252,10 @@ def irq__irq_handler_exit(name, context, cpu, sec, nsec, pid, comm, callchain, i
 	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm, irq, ret)
 	all_event_list.append(event_info)
 
-def napi__napi_poll(name, context, cpu, sec, nsec, pid, comm, callchain, napi, dev_name):
+def napi__napi_poll(name, context, cpu, sec, nsec, pid, comm, callchain, napi,
+                    dev_name, work=None, budget=None):
 	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
-			napi, dev_name)
+			napi, dev_name, work, budget)
 	all_event_list.append(event_info)
 
 def net__netif_receive_skb(name, context, cpu, sec, nsec, pid, comm, callchain, skbaddr,
@@ -354,11 +355,13 @@ def handle_irq_softirq_exit(event_info):
 	receive_hunk_list.append(rec_data)
 
 def handle_napi_poll(event_info):
-	(name, context, cpu, time, pid, comm, napi, dev_name) = event_info
+	(name, context, cpu, time, pid, comm, napi, dev_name,
+		work, budget) = event_info
 	if cpu in net_rx_dic.keys():
 		event_list = net_rx_dic[cpu]['event_list']
 		rec_data = {'event_name':'napi_poll',
-				'dev':dev_name, 'event_t':time}
+				'dev':dev_name, 'event_t':time,
+				'work':work, 'budget':budget}
 		event_list.append(rec_data)
 
 def handle_netif_rx(event_info):