tools/kvm_stat: move functions to corresponding classes (099a2dfc) · Commits · EulixOS / Software / Kernel

tools/kvm/kvm_stat/kvm_stat

+165 −162

Original line number	Diff line number	Diff line
		@@ -295,121 +295,6 @@ class ArchS390(Arch):
		ARCH = Arch.get_arch()


		def is_field_wanted(fields_filter, field):
		"""Indicate whether field is valid according to fields_filter."""
		if not fields_filter:
		return True
		return re.match(fields_filter, field) is not None


		def walkdir(path):
		"""Returns os.walk() data for specified directory.

		As it is only a wrapper it returns the same 3-tuple of (dirpath,
		dirnames, filenames).
		"""
		return next(os.walk(path))


		def parse_int_list(list_string):
		"""Returns an int list from a string of comma separated integers and
		integer ranges."""
		integers = []
		members = list_string.split(',')

		for member in members:
		if '-' not in member:
		integers.append(int(member))
		else:
		int_range = member.split('-')
		integers.extend(range(int(int_range[0]),
		int(int_range[1]) + 1))

		return integers


		def get_pid_from_gname(gname):
		"""Fuzzy function to convert guest name to QEMU process pid.

		Returns a list of potential pids, can be empty if no match found.
		Throws an exception on processing errors.

		"""
		pids = []
		try:
		child = subprocess.Popen(['ps', '-A', '--format', 'pid,args'],
		stdout=subprocess.PIPE)
		except:
		raise Exception
		for line in child.stdout:
		line = line.lstrip().split(' ', 1)
		# perform a sanity check before calling the more expensive
		# function to possibly extract the guest name
		if ' -name ' in line[1] and gname == get_gname_from_pid(line[0]):
		pids.append(int(line[0]))
		child.stdout.close()

		return pids


		def get_gname_from_pid(pid):
		"""Returns the guest name for a QEMU process pid.

		Extracts the guest name from the QEMU comma line by processing the '-name'
		option. Will also handle names specified out of sequence.

		"""
		name = ''
		try:
		line = open('/proc/{}/cmdline'.format(pid), 'rb').read().split('\0')
		parms = line[line.index('-name') + 1].split(',')
		while '' in parms:
		# commas are escaped (i.e. ',,'), hence e.g. 'foo,bar' results in
		# ['foo', '', 'bar'], which we revert here
		idx = parms.index('')
		parms[idx - 1] += ',' + parms[idx + 1]
		del parms[idx:idx+2]
		# the '-name' switch allows for two ways to specify the guest name,
		# where the plain name overrides the name specified via 'guest='
		for arg in parms:
		if '=' not in arg:
		name = arg
		break
		if arg[:6] == 'guest=':
		name = arg[6:]
		except (ValueError, IOError, IndexError):
		pass

		return name


		def get_online_cpus():
		"""Returns a list of cpu id integers."""
		with open('/sys/devices/system/cpu/online') as cpu_list:
		cpu_string = cpu_list.readline()
		return parse_int_list(cpu_string)


		def get_filters():
		"""Returns a dict of trace events, their filter ids and
		the values that can be filtered.

		Trace events can be filtered for special values by setting a
		filter string via an ioctl. The string normally has the format
		identifier==value. For each filter a new event will be created, to
		be able to distinguish the events.

		"""
		filters = {}
		filters['kvm_userspace_exit'] = ('reason', USERSPACE_EXIT_REASONS)
		if ARCH.exit_reasons:
		filters['kvm_exit'] = ('exit_reason', ARCH.exit_reasons)
		return filters

		libc = ctypes.CDLL('libc.so.6', use_errno=True)
		syscall = libc.syscall


		class perf_event_attr(ctypes.Structure):
		"""Struct that holds the necessary data to set up a trace event.

		@@ -439,25 +324,6 @@ class perf_event_attr(ctypes.Structure):
		self.read_format = PERF_FORMAT_GROUP


		def perf_event_open(attr, pid, cpu, group_fd, flags):
		"""Wrapper for the sys_perf_evt_open() syscall.

		Used to set up performance events, returns a file descriptor or -1
		on error.

		Attributes are:
		- syscall number
		- struct perf_event_attr *
		- pid or -1 to monitor all pids
		- cpu number or -1 to monitor all cpus
		- The file descriptor of the group leader or -1 to create a group.
		- flags

		"""
		return syscall(ARCH.sc_perf_evt_open, ctypes.pointer(attr),
		ctypes.c_int(pid), ctypes.c_int(cpu),
		ctypes.c_int(group_fd), ctypes.c_long(flags))

		PERF_TYPE_TRACEPOINT = 2
		PERF_FORMAT_GROUP = 1 << 3

		@@ -502,6 +368,8 @@ class Event(object):
		"""Represents a performance event and manages its life cycle."""
		def __init__(self, name, group, trace_cpu, trace_pid, trace_point,
		trace_filter, trace_set='kvm'):
		self.libc = ctypes.CDLL('libc.so.6', use_errno=True)
		self.syscall = self.libc.syscall
		self.name = name
		self.fd = None
		self.setup_event(group, trace_cpu, trace_pid, trace_point,
		@@ -518,6 +386,25 @@ class Event(object):
		if self.fd:
		os.close(self.fd)

		def perf_event_open(self, attr, pid, cpu, group_fd, flags):
		"""Wrapper for the sys_perf_evt_open() syscall.

		Used to set up performance events, returns a file descriptor or -1
		on error.

		Attributes are:
		- syscall number
		- struct perf_event_attr *
		- pid or -1 to monitor all pids
		- cpu number or -1 to monitor all cpus
		- The file descriptor of the group leader or -1 to create a group.
		- flags

		"""
		return self.syscall(ARCH.sc_perf_evt_open, ctypes.pointer(attr),
		ctypes.c_int(pid), ctypes.c_int(cpu),
		ctypes.c_int(group_fd), ctypes.c_long(flags))

		def setup_event_attribute(self, trace_set, trace_point):
		"""Returns an initialized ctype perf_event_attr struct."""

		@@ -546,7 +433,7 @@ class Event(object):
		if group.events:
		group_leader = group.events[0].fd

		fd = perf_event_open(event_attr, trace_pid,
		fd = self.perf_event_open(event_attr, trace_pid,
		trace_cpu, group_leader, 0)
		if fd == -1:
		err = ctypes.get_errno()
		@@ -582,7 +469,26 @@ class Event(object):
		fcntl.ioctl(self.fd, ARCH.ioctl_numbers['RESET'], 0)


		class TracepointProvider(object):
		class Provider(object):
		"""Encapsulates functionalities used by all providers."""
		@staticmethod
		def is_field_wanted(fields_filter, field):
		"""Indicate whether field is valid according to fields_filter."""
		if not fields_filter:
		return True
		return re.match(fields_filter, field) is not None

		@staticmethod
		def walkdir(path):
		"""Returns os.walk() data for specified directory.

		As it is only a wrapper it returns the same 3-tuple of (dirpath,
		dirnames, filenames).
		"""
		return next(os.walk(path))


		class TracepointProvider(Provider):
		"""Data provider for the stats class.

		Manages the events/groups from which it acquires its data.
		@@ -590,10 +496,27 @@ class TracepointProvider(object):
		"""
		def __init__(self, pid, fields_filter):
		self.group_leaders = []
		self.filters = get_filters()
		self.filters = self.get_filters()
		self.update_fields(fields_filter)
		self.pid = pid

		@staticmethod
		def get_filters():
		"""Returns a dict of trace events, their filter ids and
		the values that can be filtered.

		Trace events can be filtered for special values by setting a
		filter string via an ioctl. The string normally has the format
		identifier==value. For each filter a new event will be created, to
		be able to distinguish the events.

		"""
		filters = {}
		filters['kvm_userspace_exit'] = ('reason', USERSPACE_EXIT_REASONS)
		if ARCH.exit_reasons:
		filters['kvm_exit'] = ('exit_reason', ARCH.exit_reasons)
		return filters

		def get_available_fields(self):
		"""Returns a list of available event's of format 'event name(filter
		name)'.
		@@ -610,7 +533,7 @@ class TracepointProvider(object):

		"""
		path = os.path.join(PATH_DEBUGFS_TRACING, 'events', 'kvm')
		fields = walkdir(path)[1]
		fields = self.walkdir(path)[1]
		extra = []
		for field in fields:
		if field in self.filters:
		@@ -623,7 +546,30 @@ class TracepointProvider(object):
		def update_fields(self, fields_filter):
		"""Refresh fields, applying fields_filter"""
		self._fields = [field for field in self.get_available_fields()
		if is_field_wanted(fields_filter, field)]
		if self.is_field_wanted(fields_filter, field)]

		@staticmethod
		def get_online_cpus():
		"""Returns a list of cpu id integers."""
		def parse_int_list(list_string):
		"""Returns an int list from a string of comma separated integers and
		integer ranges."""
		integers = []
		members = list_string.split(',')

		for member in members:
		if '-' not in member:
		integers.append(int(member))
		else:
		int_range = member.split('-')
		integers.extend(range(int(int_range[0]),
		int(int_range[1]) + 1))

		return integers

		with open('/sys/devices/system/cpu/online') as cpu_list:
		cpu_string = cpu_list.readline()
		return parse_int_list(cpu_string)

		def setup_traces(self):
		"""Creates all event and group objects needed to be able to retrieve
		@@ -633,9 +579,9 @@ class TracepointProvider(object):
		# Fetch list of all threads of the monitored pid, as qemu
		# starts a thread for each vcpu.
		path = os.path.join('/proc', str(self._pid), 'task')
		groupids = walkdir(path)[1]
		groupids = self.walkdir(path)[1]
		else:
		groupids = get_online_cpus()
		groupids = self.get_online_cpus()

		# The constant is needed as a buffer for python libs, std
		# streams and other files that the script opens.
		@@ -732,7 +678,7 @@ class TracepointProvider(object):
		event.reset()


		class DebugfsProvider(object):
		class DebugfsProvider(Provider):
		"""Provides data from the files that KVM creates in the kvm debugfs
		folder."""
		def __init__(self, pid, fields_filter):
		@@ -748,12 +694,12 @@ class DebugfsProvider(object):
		The fields are all available KVM debugfs files

		"""
		return walkdir(PATH_DEBUGFS_KVM)[2]
		return self.walkdir(PATH_DEBUGFS_KVM)[2]

		def update_fields(self, fields_filter):
		"""Refresh fields, applying fields_filter"""
		self._fields = [field for field in self.get_available_fields()
		if is_field_wanted(fields_filter, field)]
		if self.is_field_wanted(fields_filter, field)]

		@property
		def fields(self):
		@@ -772,7 +718,7 @@ class DebugfsProvider(object):
		def pid(self, pid):
		self._pid = pid
		if pid != 0:
		vms = walkdir(PATH_DEBUGFS_KVM)[1]
		vms = self.walkdir(PATH_DEBUGFS_KVM)[1]
		if len(vms) == 0:
		self.do_read = False

		@@ -834,11 +780,23 @@ class Stats(object):

		"""
		def __init__(self, options):
		self.providers = get_providers(options)
		self.providers = self.get_providers(options)
		self._pid_filter = options.pid
		self._fields_filter = options.fields
		self.values = {}

		@staticmethod
		def get_providers(options):
		"""Returns a list of data providers depending on the passed options."""
		providers = []

		if options.debugfs:
		providers.append(DebugfsProvider(options.pid, options.fields))
		if options.tracepoints or not providers:
		providers.append(TracepointProvider(options.pid, options.fields))

		return providers

		def update_provider_filters(self):
		"""Propagates fields filters to providers."""
		# As we reset the counters when updating the fields we can
		@@ -933,6 +891,63 @@ class Tui(object):
		curses.nocbreak()
		curses.endwin()

		@staticmethod
		def get_pid_from_gname(gname):
		"""Fuzzy function to convert guest name to QEMU process pid.

		Returns a list of potential pids, can be empty if no match found.
		Throws an exception on processing errors.

		"""
		pids = []
		try:
		child = subprocess.Popen(['ps', '-A', '--format', 'pid,args'],
		stdout=subprocess.PIPE)
		except:
		raise Exception
		for line in child.stdout:
		line = line.lstrip().split(' ', 1)
		# perform a sanity check before calling the more expensive
		# function to possibly extract the guest name
		if (' -name ' in line[1] and
		gname == self.get_gname_from_pid(line[0])):
		pids.append(int(line[0]))
		child.stdout.close()

		return pids

		@staticmethod
		def get_gname_from_pid(pid):
		"""Returns the guest name for a QEMU process pid.

		Extracts the guest name from the QEMU comma line by processing the
		'-name' option. Will also handle names specified out of sequence.

		"""
		name = ''
		try:
		line = open('/proc/{}/cmdline'
		.format(pid), 'rb').read().split('\0')
		parms = line[line.index('-name') + 1].split(',')
		while '' in parms:
		# commas are escaped (i.e. ',,'), hence e.g. 'foo,bar' results
		# in # ['foo', '', 'bar'], which we revert here
		idx = parms.index('')
		parms[idx - 1] += ',' + parms[idx + 1]
		del parms[idx:idx+2]
		# the '-name' switch allows for two ways to specify the guest name,
		# where the plain name overrides the name specified via 'guest='
		for arg in parms:
		if '=' not in arg:
		name = arg
		break
		if arg[:6] == 'guest=':
		name = arg[6:]
		except (ValueError, IOError, IndexError):
		pass

		return name

		def update_drilldown(self):
		"""Sets or removes a filter that only allows fields without braces."""
		if not self.stats.fields_filter:
		@@ -950,7 +965,7 @@ class Tui(object):
		if pid is None:
		pid = self.stats.pid_filter
		self.screen.erase()
		gname = get_gname_from_pid(pid)
		gname = self.get_gname_from_pid(pid)
		if gname:
		gname = ('({})'.format(gname[:MAX_GUEST_NAME_LEN] + '...'
		if len(gname) > MAX_GUEST_NAME_LEN
		@@ -1096,7 +1111,7 @@ class Tui(object):
		else:
		pids = []
		try:
		pids = get_pid_from_gname(gname)
		pids = self.get_pid_from_gname(gname)
		except:
		msg = '"' + gname + '": Internal error while searching, ' \
		'use pid filter instead'
		@@ -1229,7 +1244,7 @@ Press any other key to refresh statistics immediately.

		def cb_guest_to_pid(option, opt, val, parser):
		try:
		pids = get_pid_from_gname(val)
		pids = Tui.get_pid_from_gname(val)
		except:
		raise optparse.OptionValueError('Error while searching for guest '
		'"{}", use "-p" to specify a pid '
		@@ -1294,18 +1309,6 @@ Press any other key to refresh statistics immediately.
		return options


		def get_providers(options):
		"""Returns a list of data providers depending on the passed options."""
		providers = []

		if options.debugfs:
		providers.append(DebugfsProvider(options.pid, options.fields))
		if options.tracepoints or not providers:
		providers.append(TracepointProvider(options.pid, options.fields))

		return providers


		def check_access(options):
		"""Exits if the current user can't access all needed directories."""
		if not os.path.exists('/sys/kernel/debug'):