Re: [RFC PATCH v4 5/5] perf:add a script shows a process of packet

[Neil Horman]

On Wed, Jul 28, 2010 at 03:35:16PM +0900, Koki Sanagi wrote:
> Add a perf script which shows a process of packets and processed time.
> It helps us to investigate networking or network device.
> 
> If you want to use it, install perf and record perf.data like following.
> 
> #perf trace record netdev-times [script]
> 
> If you set script, perf gathers records until it ends.
> If not, you must Ctrl-C to stop recording.
> 
> And if you want a report from record,
> 
> #perf trace report netdev-times [options]
> 
> If you use some options, you can limit an output.
> Option is below.
> 
> tx: show only process of tx packets
> rx: show only process of rx packets
> dev=: show a process specified with this option
> debug: work with debug mode. It shows buffer status.
> 
> For example, if you want to show a process of received packets associated
> with eth4,
> 
> #perf trace report netdev-times rx dev=eth4
> 106133.171439sec cpu=0
>   irq_entry(+0.000msec irq=24:eth4)
>          |
>   softirq_entry(+0.006msec)
>          |
>          |---netif_receive_skb(+0.010msec skb=f2d15900 len=100)
>          |            |
>          |      skb_copy_datagram_iovec(+0.039msec 10291::10291)
>          |
>   napi_poll_exit(+0.022msec eth4)
> 
> This perf script helps us to analyze a process time of transmit/receive
> sequence.
> 
> Signed-off-by: Koki Sanagi <sanagi.koki@xxxxxxxxxxxxxx>
Acked-by: Neil Horman <nhorman@xxxxxxxxxxxxx>

> ---
>  tools/perf/scripts/python/bin/netdev-times-record |    8 +
>  tools/perf/scripts/python/bin/netdev-times-report |    5 +
>  tools/perf/scripts/python/netdev-times.py         |  464 +++++++++++++++++++++
>  3 files changed, 477 insertions(+), 0 deletions(-)
> 
> diff --git a/tools/perf/scripts/python/bin/netdev-times-record b/tools/perf/scripts/python/bin/netdev-times-record
> new file mode 100644
> index 0000000..2b59511
> --- /dev/null
> +++ b/tools/perf/scripts/python/bin/netdev-times-record
> @@ -0,0 +1,8 @@
> +#!/bin/bash
> +perf record -c 1 -f -R -a -e net:net_dev_xmit -e net:net_dev_queue	\
> +		-e net:netif_receive_skb -e net:netif_rx		\
> +		-e skb:consume_skb -e skb:kfree_skb			\
> +		-e skb:skb_copy_datagram_iovec -e napi:napi_poll	\
> +		-e irq:irq_handler_entry -e irq:irq_handler_exit	\
> +		-e irq:softirq_entry -e irq:softirq_exit		\
> +		-e irq:softirq_raise $@
> diff --git a/tools/perf/scripts/python/bin/netdev-times-report b/tools/perf/scripts/python/bin/netdev-times-report
> new file mode 100644
> index 0000000..c3d0a63
> --- /dev/null
> +++ b/tools/perf/scripts/python/bin/netdev-times-report
> @@ -0,0 +1,5 @@
> +#!/bin/bash
> +# description: display a process of packet and processing time
> +# args: [tx] [rx] [dev=] [debug]
> +
> +perf trace -s ~/libexec/perf-core/scripts/python/netdev-times.py $@
> diff --git a/tools/perf/scripts/python/netdev-times.py b/tools/perf/scripts/python/netdev-times.py
> new file mode 100644
> index 0000000..9aa0a32
> --- /dev/null
> +++ b/tools/perf/scripts/python/netdev-times.py
> @@ -0,0 +1,464 @@
> +# Display a process of packets and processed time.
> +# It helps us to investigate networking or network device.
> +#
> +# options
> +# tx: show only tx chart
> +# rx: show only rx chart
> +# dev=: show only thing related to specified device
> +# debug: work with debug mode. It shows buffer status.
> +
> +import os
> +import sys
> +
> +sys.path.append(os.environ['PERF_EXEC_PATH'] + \
> +	'/scripts/python/Perf-Trace-Util/lib/Perf/Trace')
> +
> +from perf_trace_context import *
> +from Core import *
> +from Util import *
> +
> +all_event_list = []; # insert all tracepoint event related with this script
> +irq_dic = {}; # key is cpu and value is a list which stacks irqs
> +              # which raise NET_RX softirq
> +net_rx_dic = {}; # key is cpu and value include time of NET_RX softirq-entry
> +		 # and a list which stacks receive
> +receive_hunk_list = []; # a list which include a sequence of receive events
> +rx_skb_list = []; # received packet list for matching
> +		       # skb_copy_datagram_iovec
> +
> +buffer_budget = 65536; # the budget of rx_skb_list, tx_queue_list and
> +		       # tx_xmit_list
> +of_count_rx_skb_list = 0; # overflow count
> +
> +tx_queue_list = []; # list of packets which pass through dev_queue_xmit
> +of_count_tx_queue_list = 0; # overflow count
> +
> +tx_xmit_list = [];  # list of packets which pass through dev_hard_start_xmit
> +of_count_tx_xmit_list = 0; # overflow count
> +
> +tx_free_list = [];  # list of packets which is freed
> +
> +# options
> +show_tx = 0;
> +show_rx = 0;
> +dev = 0; # store a name of device specified by option "dev="
> +debug = 0;
> +
> +# indices of event_info tuple
> +EINFO_IDX_NAME=   0
> +EINFO_IDX_CONTEXT=1
> +EINFO_IDX_CPU=    2
> +EINFO_IDX_TIME=   3
> +EINFO_IDX_PID=    4
> +EINFO_IDX_COMM=   5
> +
> +# Calculate a time interval(msec) from src(nsec) to dst(nsec)
> +def diff_msec(src, dst):
> +	return (dst - src) / 1000000.0
> +
> +# Display a process of transmitting a packet
> +def print_transmit(hunk):
> +	if dev != 0 and hunk['dev'].find(dev) < 0:
> +		return
> +	print "%7s %5d %6d.%06dsec %12.3fmsec      %12.3fmsec" % \
> +		(hunk['dev'], hunk['len'],
> +		nsecs_secs(hunk['queue_t']),
> +		nsecs_nsecs(hunk['queue_t'])/1000,
> +		diff_msec(hunk['queue_t'], hunk['xmit_t']),
> +		diff_msec(hunk['xmit_t'], hunk['free_t']))
> +
> +# Format for displaying rx packet processing
> +PF_IRQ_ENTRY= "  irq_entry(+%.3fmsec irq=%d:%s)"
> +PF_SOFT_ENTRY="  softirq_entry(+%.3fmsec)"
> +PF_NAPI_POLL= "  napi_poll_exit(+%.3fmsec %s)"
> +PF_JOINT=     "         |"
> +PF_WJOINT=    "         |            |"
> +PF_NET_RECV=  "         |---netif_receive_skb(+%.3fmsec skb=%x len=%d)"
> +PF_NET_RX=    "         |---netif_rx(+%.3fmsec skb=%x)"
> +PF_CPY_DGRAM= "         |      skb_copy_datagram_iovec(+%.3fmsec %d:%s)"
> +PF_KFREE_SKB= "         |      kfree_skb(+%.3fmsec location=%x)"
> +PF_CONS_SKB=  "         |      consume_skb(+%.3fmsec)"
> +
> +# Display a process of received packets and interrputs associated with
> +# a NET_RX softirq
> +def print_receive(hunk):
> +	show_hunk = 0
> +	irq_list = hunk['irq_list']
> +	cpu = irq_list[0]['cpu']
> +	base_t = irq_list[0]['irq_ent_t']
> +	# check if this hunk should be showed
> +	if dev != 0:
> +		for i in range(len(irq_list)):
> +			if irq_list[i]['name'].find(dev) >= 0:
> +				show_hunk = 1
> +				break
> +	else:
> +		show_hunk = 1
> +	if show_hunk == 0:
> +		return
> +
> +	print "%d.%06dsec cpu=%d" % \
> +		(nsecs_secs(base_t), nsecs_nsecs(base_t)/1000, cpu)
> +	for i in range(len(irq_list)):
> +		print PF_IRQ_ENTRY % \
> +			(diff_msec(base_t, irq_list[i]['irq_ent_t']),
> +			irq_list[i]['irq'], irq_list[i]['name'])
> +		print PF_JOINT
> +		irq_event_list = irq_list[i]['event_list']
> +		for j in range(len(irq_event_list)):
> +			irq_event = irq_event_list[j]
> +			if irq_event['event'] == 'netif_rx':
> +				print PF_NET_RX % \
> +					(diff_msec(base_t, irq_event['time']),
> +					irq_event['skbaddr'])
> +				print PF_JOINT
> +	print PF_SOFT_ENTRY % \
> +		diff_msec(base_t, hunk['sirq_ent_t'])
> +	print PF_JOINT
> +	event_list = hunk['event_list']
> +	for i in range(len(event_list)):
> +		event = event_list[i]
> +		if event['event_name'] == 'napi_poll':
> +			print PF_NAPI_POLL % \
> +			    (diff_msec(base_t, event['event_t']), event['dev'])
> +			if i == len(event_list) - 1:
> +				print ""
> +			else:
> +				print PF_JOINT
> +		else:
> +			print PF_NET_RECV % \
> +			    (diff_msec(base_t, event['event_t']), event['skbaddr'],
> +				event['len'])
> +			if 'comm' in event.keys():
> +				print PF_WJOINT
> +				print PF_CPY_DGRAM % \
> +					(diff_msec(base_t, event['comm_t']),
> +					event['pid'], event['comm'])
> +			elif 'handle' in event.keys():
> +				print PF_WJOINT
> +				if event['handle'] == "kfree_skb":
> +					print PF_KFREE_SKB % \
> +						(diff_msec(base_t,
> +						event['comm_t']),
> +						event['location'])
> +				elif event['handle'] == "consume_skb":
> +					print PF_CONS_SKB % \
> +						diff_msec(base_t,
> +							event['comm_t'])
> +			print PF_JOINT
> +
> +def trace_begin():
> +	global show_tx
> +	global show_rx
> +	global dev
> +	global debug
> +
> +	for i in range(len(sys.argv)):
> +		if i == 0:
> +			continue
> +		arg = sys.argv[i]
> +		if arg == 'tx':
> +			show_tx = 1
> +		elif arg =='rx':
> +			show_rx = 1
> +		elif arg.find('dev=',0, 4) >= 0:
> +			dev = arg[4:]
> +		elif arg == 'debug':
> +			debug = 1
> +	if show_tx == 0  and show_rx == 0:
> +		show_tx = 1
> +		show_rx = 1
> +
> +def trace_end():
> +	# order all events in time
> +	all_event_list.sort(lambda a,b :cmp(a[EINFO_IDX_TIME],
> +					    b[EINFO_IDX_TIME]))
> +	# process all events
> +	for i in range(len(all_event_list)):
> +		event_info = all_event_list[i]
> +		name = event_info[EINFO_IDX_NAME]
> +		if name == 'irq__softirq_exit':
> +			handle_irq_softirq_exit(event_info)
> +		elif name == 'irq__softirq_entry':
> +			handle_irq_softirq_entry(event_info)
> +		elif name == 'irq__softirq_raise':
> +			handle_irq_softirq_raise(event_info)
> +		elif name == 'irq__irq_handler_entry':
> +			handle_irq_handler_entry(event_info)
> +		elif name == 'irq__irq_handler_exit':
> +			handle_irq_handler_exit(event_info)
> +		elif name == 'napi__napi_poll':
> +			handle_napi_poll(event_info)
> +		elif name == 'net__netif_receive_skb':
> +			handle_netif_receive_skb(event_info)
> +		elif name == 'net__netif_rx':
> +			handle_netif_rx(event_info)
> +		elif name == 'skb__skb_copy_datagram_iovec':
> +			handle_skb_copy_datagram_iovec(event_info)
> +		elif name == 'net__net_dev_queue':
> +			handle_net_dev_queue(event_info)
> +		elif name == 'net__net_dev_xmit':
> +			handle_net_dev_xmit(event_info)
> +		elif name == 'skb__kfree_skb':
> +			handle_kfree_skb(event_info)
> +		elif name == 'skb__consume_skb':
> +			handle_consume_skb(event_info)
> +	# display receive hunks
> +	if show_rx:
> +		for i in range(len(receive_hunk_list)):
> +			print_receive(receive_hunk_list[i])
> +	# display transmit hunks
> +	if show_tx:
> +		print "   dev    len      Qdisc        " \
> +			"       netdevice             free"
> +		for i in range(len(tx_free_list)):
> +			print_transmit(tx_free_list[i])
> +	if debug:
> +		print "debug buffer status"
> +		print "----------------------------"
> +		print "xmit Qdisc:remain:%d overflow:%d" % \
> +			(len(tx_queue_list), of_count_tx_queue_list)
> +		print "xmit netdevice:remain:%d overflow:%d" % \
> +			(len(tx_xmit_list), of_count_tx_xmit_list)
> +		print "receive:remain:%d overflow:%d" % \
> +			(len(rx_skb_list), of_count_rx_skb_list)
> +
> +# called from perf, when it finds a correspoinding event
> +def irq__softirq_entry(name, context, cpu, sec, nsec, pid, comm, vec):
> +	if symbol_str("irq__softirq_entry", "vec", vec) != "NET_RX":
> +		return
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm, vec)
> +	all_event_list.append(event_info)
> +
> +def irq__softirq_exit(name, context, cpu, sec, nsec, pid, comm, vec):
> +	if symbol_str("irq__softirq_entry", "vec", vec) != "NET_RX":
> +		return
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm, vec)
> +	all_event_list.append(event_info)
> +
> +def irq__softirq_raise(name, context, cpu, sec, nsec, pid, comm, vec):
> +	if symbol_str("irq__softirq_entry", "vec", vec) != "NET_RX":
> +		return
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm, vec)
> +	all_event_list.append(event_info)
> +
> +def irq__irq_handler_entry(name, context, cpu, sec, nsec, pid, comm,
> +			irq, irq_name):
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
> +			irq, irq_name)
> +	all_event_list.append(event_info)
> +
> +def irq__irq_handler_exit(name, context, cpu, sec, nsec, pid, comm, irq, ret):
> +	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, napi, dev_name):
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
> +			napi, dev_name)
> +	all_event_list.append(event_info)
> +
> +def net__netif_receive_skb(name, context, cpu, sec, nsec, pid, comm, skbaddr,
> +			skblen, dev_name):
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
> +			skbaddr, skblen, dev_name)
> +	all_event_list.append(event_info)
> +
> +def net__netif_rx(name, context, cpu, sec, nsec, pid, comm, skbaddr,
> +			skblen, dev_name):
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
> +			skbaddr, skblen, dev_name)
> +	all_event_list.append(event_info)
> +
> +def net__net_dev_queue(name, context, cpu, sec, nsec, pid, comm,
> +			skbaddr, skblen, dev_name):
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
> +			skbaddr, skblen, dev_name)
> +	all_event_list.append(event_info)
> +
> +def net__net_dev_xmit(name, context, cpu, sec, nsec, pid, comm,
> +			skbaddr, skblen, rc, dev_name):
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
> +			skbaddr, skblen, rc ,dev_name)
> +	all_event_list.append(event_info)
> +
> +def skb__kfree_skb(name, context, cpu, sec, nsec, pid, comm,
> +			skbaddr, protocol, location):
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
> +			skbaddr, protocol, location)
> +	all_event_list.append(event_info)
> +
> +def skb__consume_skb(name, context, cpu, sec, nsec, pid, comm, skbaddr):
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
> +			skbaddr)
> +	all_event_list.append(event_info)
> +
> +def skb__skb_copy_datagram_iovec(name, context, cpu, sec, nsec, pid, comm,
> +	skbaddr, skblen):
> +	event_info = (name, context, cpu, nsecs(sec, nsec), pid, comm,
> +			skbaddr, skblen)
> +	all_event_list.append(event_info)
> +
> +def handle_irq_handler_entry(event_info):
> +	(name, context, cpu, time, pid, comm, irq, irq_name) = event_info
> +	if cpu not in irq_dic.keys():
> +		irq_dic[cpu] = []
> +	irq_record = {'irq':irq, 'name':irq_name, 'cpu':cpu, 'irq_ent_t':time}
> +	irq_dic[cpu].append(irq_record)
> +
> +def handle_irq_handler_exit(event_info):
> +	(name, context, cpu, time, pid, comm, irq, ret) = event_info
> +	if cpu not in irq_dic.keys():
> +		return
> +	irq_record = irq_dic[cpu].pop()
> +	if irq != irq_record['irq']:
> +		return
> +	irq_record.update({'irq_ext_t':time})
> +	# if an irq doesn't include NET_RX softirq, drop.
> +	if 'event_list' in irq_record.keys():
> +		irq_dic[cpu].append(irq_record)
> +
> +def handle_irq_softirq_raise(event_info):
> +	(name, context, cpu, time, pid, comm, vec) = event_info
> +	if cpu not in irq_dic.keys() \
> +	or len(irq_dic[cpu]) == 0:
> +		return
> +	irq_record = irq_dic[cpu].pop()
> +	if 'event_list' in irq_record.keys():
> +		irq_event_list = irq_record['event_list']
> +	else:
> +		irq_event_list = []
> +	irq_event_list.append({'time':time, 'event':'sirq_raise'})
> +	irq_record.update({'event_list':irq_event_list})
> +	irq_dic[cpu].append(irq_record)
> +
> +def handle_irq_softirq_entry(event_info):
> +	(name, context, cpu, time, pid, comm, vec) = event_info
> +	net_rx_dic[cpu] = {'sirq_ent_t':time, 'event_list':[]}
> +
> +def handle_irq_softirq_exit(event_info):
> +	(name, context, cpu, time, pid, comm, vec) = event_info
> +	irq_list = []
> +	event_list = 0
> +	if cpu in irq_dic.keys():
> +		irq_list = irq_dic[cpu]
> +		del irq_dic[cpu]
> +	if cpu in net_rx_dic.keys():
> +		sirq_ent_t = net_rx_dic[cpu]['sirq_ent_t']
> +		event_list = net_rx_dic[cpu]['event_list']
> +		del net_rx_dic[cpu]
> +	if irq_list == [] or event_list == 0:
> +		return
> +	rec_data = {'sirq_ent_t':sirq_ent_t, 'sirq_ext_t':time,
> +		    'irq_list':irq_list, 'event_list':event_list}
> +	# merge information realted to a NET_RX softirq
> +	receive_hunk_list.append(rec_data)
> +
> +def handle_napi_poll(event_info):
> +	(name, context, cpu, time, pid, comm, napi, dev_name) = 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}
> +		event_list.append(rec_data)
> +
> +def handle_netif_rx(event_info):
> +	(name, context, cpu, time, pid, comm,
> +		skbaddr, skblen, dev_name) = event_info
> +	if cpu not in irq_dic.keys() \
> +	or len(irq_dic[cpu]) == 0:
> +		return
> +	irq_record = irq_dic[cpu].pop()
> +	if 'event_list' in irq_record.keys():
> +		irq_event_list = irq_record['event_list']
> +	else:
> +		irq_event_list = []
> +	irq_event_list.append({'time':time, 'event':'netif_rx',
> +		'skbaddr':skbaddr, 'skblen':skblen, 'dev_name':dev_name})
> +	irq_record.update({'event_list':irq_event_list})
> +	irq_dic[cpu].append(irq_record)
> +
> +def handle_netif_receive_skb(event_info):
> +	global of_count_rx_skb_list
> +
> +	(name, context, cpu, time, pid, comm,
> +		skbaddr, skblen, dev_name) = event_info
> +	if cpu in net_rx_dic.keys():
> +		rec_data = {'event_name':'netif_receive_skb',
> +			    'event_t':time, 'skbaddr':skbaddr, 'len':skblen}
> +		event_list = net_rx_dic[cpu]['event_list']
> +		event_list.append(rec_data)
> +		rx_skb_list.insert(0, rec_data)
> +		if len(rx_skb_list) > buffer_budget:
> +			rx_skb_list.pop()
> +			of_count_rx_skb_list += 1
> +
> +def handle_net_dev_queue(event_info):
> +	global of_count_tx_queue_list
> +
> +	(name, context, cpu, time, pid, comm,
> +		skbaddr, skblen, dev_name) = event_info
> +	skb = {'dev':dev_name, 'skbaddr':skbaddr, 'len':skblen, 'queue_t':time}
> +	tx_queue_list.insert(0, skb)
> +	if len(tx_queue_list) > buffer_budget:
> +		tx_queue_list.pop()
> +		of_count_tx_queue_list += 1
> +
> +def handle_net_dev_xmit(event_info):
> +	global of_count_tx_xmit_list
> +
> +	(name, context, cpu, time, pid, comm,
> +		skbaddr, skblen, rc, dev_name) = event_info
> +	if rc == 0: # NETDEV_TX_OK
> +		for i in range(len(tx_queue_list)):
> +			skb = tx_queue_list[i]
> +			if skb['skbaddr'] == skbaddr:
> +				skb['xmit_t'] = time
> +				tx_xmit_list.insert(0, skb)
> +				del tx_queue_list[i]
> +				if len(tx_xmit_list) > buffer_budget:
> +					tx_xmit_list.pop()
> +					of_count_tx_xmit_list += 1
> +				return
> +
> +def handle_kfree_skb(event_info):
> +	(name, context, cpu, time, pid, comm,
> +		skbaddr, protocol, location) = event_info
> +	for i in range(len(tx_queue_list)):
> +		skb = tx_queue_list[i]
> +		if skb['skbaddr'] == skbaddr:
> +			del tx_queue_list[i]
> +			return
> +	for i in range(len(tx_xmit_list)):
> +		skb = tx_xmit_list[i]
> +		if skb['skbaddr'] == skbaddr:
> +			skb['free_t'] = time
> +			tx_free_list.append(skb)
> +			del tx_xmit_list[i]
> +			return
> +	for i in range(len(rx_skb_list)):
> +		rec_data = rx_skb_list[i]
> +		if rec_data['skbaddr'] == skbaddr:
> +			rec_data.update({'handle':"kfree_skb",
> +					'comm':comm, 'pid':pid, 'comm_t':time})
> +			del rx_skb_list[i]
> +			return
> +
> +def handle_consume_skb(event_info):
> +	(name, context, cpu, time, pid, comm, skbaddr) = event_info
> +	for i in range(len(tx_xmit_list)):
> +		skb = tx_xmit_list[i]
> +		if skb['skbaddr'] == skbaddr:
> +			skb['free_t'] = time
> +			tx_free_list.append(skb)
> +			del tx_xmit_list[i]
> +			return
> +
> +def handle_skb_copy_datagram_iovec(event_info):
> +	(name, context, cpu, time, pid, comm, skbaddr, skblen) = event_info
> +	for i in range(len(rx_skb_list)):
> +		rec_data = rx_skb_list[i]
> +		if skbaddr == rec_data['skbaddr']:
> +			rec_data.update({'handle':"skb_copy_datagram_iovec",
> +					'comm':comm, 'pid':pid, 'comm_t':time})
> +			del rx_skb_list[i]
> +			return
> 
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