kvm: Add top-like kvm statistics script

Taken from original qemu-kvm/kvm/kvm_stat.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

scripts/kvm/kvm_stat

+#!/usr/bin/python
+#
+# top-like utility for displaying kvm statistics
+#
+# Copyright 2006-2008 Qumranet Technologies
+# Copyright 2008-2011 Red Hat, Inc.
+#
+# Authors:
+#  Avi Kivity <avi@redhat.com>
+#
+# This work is licensed under the terms of the GNU GPL, version 2.  See
+# the COPYING file in the top-level directory.
+
+import curses
+import sys, os, time, optparse
+
+class DebugfsProvider(object):
+    def __init__(self):
+        self.base = '/sys/kernel/debug/kvm'
+        self._fields = os.listdir(self.base)
+    def fields(self):
+        return self._fields
+    def select(self, fields):
+        self._fields = fields
+    def read(self):
+        def val(key):
+            return int(file(self.base + '/' + key).read())
+        return dict([(key, val(key)) for key in self._fields])
+
+vmx_exit_reasons = {
+    0: 'EXCEPTION_NMI',
+    1: 'EXTERNAL_INTERRUPT',
+    2: 'TRIPLE_FAULT',
+    7: 'PENDING_INTERRUPT',
+    8: 'NMI_WINDOW',
+    9: 'TASK_SWITCH',
+    10: 'CPUID',
+    12: 'HLT',
+    14: 'INVLPG',
+    15: 'RDPMC',
+    16: 'RDTSC',
+    18: 'VMCALL',
+    19: 'VMCLEAR',
+    20: 'VMLAUNCH',
+    21: 'VMPTRLD',
+    22: 'VMPTRST',
+    23: 'VMREAD',
+    24: 'VMRESUME',
+    25: 'VMWRITE',
+    26: 'VMOFF',
+    27: 'VMON',
+    28: 'CR_ACCESS',
+    29: 'DR_ACCESS',
+    30: 'IO_INSTRUCTION',
+    31: 'MSR_READ',
+    32: 'MSR_WRITE',
+    33: 'INVALID_STATE',
+    36: 'MWAIT_INSTRUCTION',
+    39: 'MONITOR_INSTRUCTION',
+    40: 'PAUSE_INSTRUCTION',
+    41: 'MCE_DURING_VMENTRY',
+    43: 'TPR_BELOW_THRESHOLD',
+    44: 'APIC_ACCESS',
+    48: 'EPT_VIOLATION',
+    49: 'EPT_MISCONFIG',
+    54: 'WBINVD',
+    55: 'XSETBV',
+}
+
+svm_exit_reasons = {
+    0x000: 'READ_CR0',
+    0x003: 'READ_CR3',
+    0x004: 'READ_CR4',
+    0x008: 'READ_CR8',
+    0x010: 'WRITE_CR0',
+    0x013: 'WRITE_CR3',
+    0x014: 'WRITE_CR4',
+    0x018: 'WRITE_CR8',
+    0x020: 'READ_DR0',
+    0x021: 'READ_DR1',
+    0x022: 'READ_DR2',
+    0x023: 'READ_DR3',
+    0x024: 'READ_DR4',
+    0x025: 'READ_DR5',
+    0x026: 'READ_DR6',
+    0x027: 'READ_DR7',
+    0x030: 'WRITE_DR0',
+    0x031: 'WRITE_DR1',
+    0x032: 'WRITE_DR2',
+    0x033: 'WRITE_DR3',
+    0x034: 'WRITE_DR4',
+    0x035: 'WRITE_DR5',
+    0x036: 'WRITE_DR6',
+    0x037: 'WRITE_DR7',
+    0x040: 'EXCP_BASE',
+    0x060: 'INTR',
+    0x061: 'NMI',
+    0x062: 'SMI',
+    0x063: 'INIT',
+    0x064: 'VINTR',
+    0x065: 'CR0_SEL_WRITE',
+    0x066: 'IDTR_READ',
+    0x067: 'GDTR_READ',
+    0x068: 'LDTR_READ',
+    0x069: 'TR_READ',
+    0x06a: 'IDTR_WRITE',
+    0x06b: 'GDTR_WRITE',
+    0x06c: 'LDTR_WRITE',
+    0x06d: 'TR_WRITE',
+    0x06e: 'RDTSC',
+    0x06f: 'RDPMC',
+    0x070: 'PUSHF',
+    0x071: 'POPF',
+    0x072: 'CPUID',
+    0x073: 'RSM',
+    0x074: 'IRET',
+    0x075: 'SWINT',
+    0x076: 'INVD',
+    0x077: 'PAUSE',
+    0x078: 'HLT',
+    0x079: 'INVLPG',
+    0x07a: 'INVLPGA',
+    0x07b: 'IOIO',
+    0x07c: 'MSR',
+    0x07d: 'TASK_SWITCH',
+    0x07e: 'FERR_FREEZE',
+    0x07f: 'SHUTDOWN',
+    0x080: 'VMRUN',
+    0x081: 'VMMCALL',
+    0x082: 'VMLOAD',
+    0x083: 'VMSAVE',
+    0x084: 'STGI',
+    0x085: 'CLGI',
+    0x086: 'SKINIT',
+    0x087: 'RDTSCP',
+    0x088: 'ICEBP',
+    0x089: 'WBINVD',
+    0x08a: 'MONITOR',
+    0x08b: 'MWAIT',
+    0x08c: 'MWAIT_COND',
+    0x400: 'NPF',
+}
+
+vendor_exit_reasons = {
+    'vmx': vmx_exit_reasons,
+    'svm': svm_exit_reasons,
+}
+
+exit_reasons = None
+
+for line in file('/proc/cpuinfo').readlines():
+    if line.startswith('flags'):
+        for flag in line.split():
+            if flag in vendor_exit_reasons:
+                exit_reasons = vendor_exit_reasons[flag]
+
+filters = {
+    'kvm_exit': ('exit_reason', exit_reasons)
+}
+
+def invert(d):
+    return dict((x[1], x[0]) for x in d.iteritems())
+
+for f in filters:
+    filters[f] = (filters[f][0], invert(filters[f][1]))
+
+import ctypes, struct, array
+
+libc = ctypes.CDLL('libc.so.6')
+syscall = libc.syscall
+class perf_event_attr(ctypes.Structure):
+    _fields_ = [('type', ctypes.c_uint32),
+                ('size', ctypes.c_uint32),
+                ('config', ctypes.c_uint64),
+                ('sample_freq', ctypes.c_uint64),
+                ('sample_type', ctypes.c_uint64),
+                ('read_format', ctypes.c_uint64),
+                ('flags', ctypes.c_uint64),
+                ('wakeup_events', ctypes.c_uint32),
+                ('bp_type', ctypes.c_uint32),
+                ('bp_addr', ctypes.c_uint64),
+                ('bp_len', ctypes.c_uint64),
+                ]
+def _perf_event_open(attr, pid, cpu, group_fd, flags):
+    return syscall(298, ctypes.pointer(attr), ctypes.c_int(pid),
+                   ctypes.c_int(cpu), ctypes.c_int(group_fd),
+                   ctypes.c_long(flags))
+
+PERF_TYPE_HARDWARE              = 0
+PERF_TYPE_SOFTWARE              = 1
+PERF_TYPE_TRACEPOINT            = 2
+PERF_TYPE_HW_CACHE              = 3
+PERF_TYPE_RAW                   = 4
+PERF_TYPE_BREAKPOINT            = 5
+
+PERF_SAMPLE_IP                  = 1 << 0
+PERF_SAMPLE_TID                 = 1 << 1
+PERF_SAMPLE_TIME                = 1 << 2
+PERF_SAMPLE_ADDR                = 1 << 3
+PERF_SAMPLE_READ                = 1 << 4
+PERF_SAMPLE_CALLCHAIN           = 1 << 5
+PERF_SAMPLE_ID                  = 1 << 6
+PERF_SAMPLE_CPU                 = 1 << 7
+PERF_SAMPLE_PERIOD              = 1 << 8
+PERF_SAMPLE_STREAM_ID           = 1 << 9
+PERF_SAMPLE_RAW                 = 1 << 10
+
+PERF_FORMAT_TOTAL_TIME_ENABLED  = 1 << 0
+PERF_FORMAT_TOTAL_TIME_RUNNING  = 1 << 1
+PERF_FORMAT_ID                  = 1 << 2
+PERF_FORMAT_GROUP               = 1 << 3
+
+import re
+
+sys_tracing = '/sys/kernel/debug/tracing'
+
+class Group(object):
+    def __init__(self, cpu):
+        self.events = []
+        self.group_leader = None
+        self.cpu = cpu
+    def add_event(self, name, event_set, tracepoint, filter = None):
+        self.events.append(Event(group = self,
+                                 name = name, event_set = event_set,
+                                 tracepoint = tracepoint, filter = filter))
+        if len(self.events) == 1:
+            self.file = os.fdopen(self.events[0].fd)
+    def read(self):
+        bytes = 8 * (1 + len(self.events))
+        fmt = 'xxxxxxxx' + 'q' * len(self.events)
+        return dict(zip([event.name for event in self.events],
+                        struct.unpack(fmt, self.file.read(bytes))))
+
+class Event(object):
+    def __init__(self, group, name, event_set, tracepoint, filter = None):
+        self.name = name
+        attr = perf_event_attr()
+        attr.type = PERF_TYPE_TRACEPOINT
+        attr.size = ctypes.sizeof(attr)
+        id_path = os.path.join(sys_tracing, 'events', event_set,
+                               tracepoint, 'id')
+        id = int(file(id_path).read())
+        attr.config = id
+        attr.sample_type = (PERF_SAMPLE_RAW
+                            | PERF_SAMPLE_TIME
+                            | PERF_SAMPLE_CPU)
+        attr.sample_period = 1
+        attr.read_format = PERF_FORMAT_GROUP
+        group_leader = -1
+        if group.events:
+            group_leader = group.events[0].fd
+        fd = _perf_event_open(attr, -1, group.cpu, group_leader, 0)
+        if fd == -1:
+            raise Exception('perf_event_open failed')
+        if filter:
+            import fcntl
+            fcntl.ioctl(fd, 0x40082406, filter)
+        self.fd = fd
+    def enable(self):
+        import fcntl
+        fcntl.ioctl(self.fd, 0x00002400, 0)
+    def disable(self):
+        import fcntl
+        fcntl.ioctl(self.fd, 0x00002401, 0)
+
+class TracepointProvider(object):
+    def __init__(self):
+        path = os.path.join(sys_tracing, 'events', 'kvm')
+        fields = [f
+                  for f in os.listdir(path)
+                  if os.path.isdir(os.path.join(path, f))]
+        extra = []
+        for f in fields:
+            if f in filters:
+                subfield, values = filters[f]
+                for name, number in values.iteritems():
+                    extra.append(f + '(' + name + ')')
+        fields += extra
+        self._setup(fields)
+        self.select(fields)
+    def fields(self):
+        return self._fields
+    def _setup(self, _fields):
+        self._fields = _fields
+        cpure = r'cpu([0-9]+)'
+        self.cpus = [int(re.match(cpure, x).group(1))
+                     for x in os.listdir('/sys/devices/system/cpu')
+                     if re.match(cpure, x)]
+        import resource
+        nfiles = len(self.cpus) * 1000
+        resource.setrlimit(resource.RLIMIT_NOFILE, (nfiles, nfiles))
+        events = []
+        self.group_leaders = []
+        for cpu in self.cpus:
+            group = Group(cpu)
+            for name in _fields:
+                tracepoint = name
+                filter = None
+                m = re.match(r'(.*)\((.*)\)', name)
+                if m:
+                    tracepoint, sub = m.groups()
+                    filter = '%s==%d\0' % (filters[tracepoint][0],
+                                           filters[tracepoint][1][sub])
+                event = group.add_event(name, event_set = 'kvm',
+                                        tracepoint = tracepoint,
+                                        filter = filter)
+            self.group_leaders.append(group)
+    def select(self, fields):
+        for group in self.group_leaders:
+            for event in group.events:
+                if event.name in fields:
+                    event.enable()
+                else:
+                    event.disable()
+    def read(self):
+        from collections import defaultdict
+        ret = defaultdict(int)
+        for group in self.group_leaders:
+            for name, val in group.read().iteritems():
+                ret[name] += val
+        return ret
+
+class Stats:
+    def __init__(self, provider, fields = None):
+        self.provider = provider
+        self.fields_filter = fields
+        self._update()
+    def _update(self):
+        def wanted(key):
+            import re
+            if not self.fields_filter:
+                return True
+            return re.match(self.fields_filter, key) is not None
+        self.values = dict([(key, None)
+                            for key in provider.fields()
+                            if wanted(key)])
+        self.provider.select(self.values.keys())
+    def set_fields_filter(self, fields_filter):
+        self.fields_filter = fields_filter
+        self._update()
+    def get(self):
+        new = self.provider.read()
+        for key in self.provider.fields():
+            oldval = self.values.get(key, (0, 0))
+            newval = new[key]
+            newdelta = None
+            if oldval is not None:
+                newdelta = newval - oldval[0]
+            self.values[key] = (newval, newdelta)
+        return self.values
+
+if not os.access('/sys/kernel/debug', os.F_OK):
+    print 'Please enable CONFIG_DEBUG_FS in your kernel'
+    sys.exit(1)
+if not os.access('/sys/kernel/debug/kvm', os.F_OK):
+    print "Please mount debugfs ('mount -t debugfs debugfs /sys/kernel/debug')"
+    print "and ensure the kvm modules are loaded"
+    sys.exit(1)
+
+label_width = 40
+number_width = 10
+
+def tui(screen, stats):
+    curses.use_default_colors()
+    curses.noecho()
+    drilldown = False
+    fields_filter = stats.fields_filter
+    def update_drilldown():
+        if not fields_filter:
+            if drilldown:
+                stats.set_fields_filter(None)
+            else:
+                stats.set_fields_filter(r'^[^\(]*$')
+    update_drilldown()
+    def refresh(sleeptime):
+        screen.erase()
+        screen.addstr(0, 0, 'kvm statistics')
+        row = 2
+        s = stats.get()
+        def sortkey(x):
+            if s[x][1]:
+                return (-s[x][1], -s[x][0])
+            else:
+                return (0, -s[x][0])
+        for key in sorted(s.keys(), key = sortkey):
+            if row >= screen.getmaxyx()[0]:
+                break
+            values = s[key]
+            if not values[0] and not values[1]:
+                break
+            col = 1
+            screen.addstr(row, col, key)
+            col += label_width
+            screen.addstr(row, col, '%10d' % (values[0],))
+            col += number_width
+            if values[1] is not None:
+                screen.addstr(row, col, '%8d' % (values[1] / sleeptime,))
+            row += 1
+        screen.refresh()
+
+    sleeptime = 0.25
+    while True:
+        refresh(sleeptime)
+        curses.halfdelay(int(sleeptime * 10))
+        sleeptime = 3
+        try:
+            c = screen.getkey()
+            if c == 'x':
+                drilldown = not drilldown
+                update_drilldown()
+            if c == 'q':
+                break
+        except KeyboardInterrupt:
+            break
+        except curses.error:
+            continue
+
+def batch(stats):
+    s = stats.get()
+    time.sleep(1)
+    s = stats.get()
+    for key in sorted(s.keys()):
+        values = s[key]
+        print '%-22s%10d%10d' % (key, values[0], values[1])
+
+def log(stats):
+    keys = sorted(stats.get().iterkeys())
+    def banner():
+        for k in keys:
+            print '%10s' % k[0:9],
+        print
+    def statline():
+        s = stats.get()
+        for k in keys:
+            print ' %9d' % s[k][1],
+        print
+    line = 0
+    banner_repeat = 20
+    while True:
+        time.sleep(1)
+        if line % banner_repeat == 0:
+            banner()
+        statline()
+        line += 1
+
+options = optparse.OptionParser()
+options.add_option('-1', '--once', '--batch',
+                   action = 'store_true',
+                   default = False,
+                   dest = 'once',
+                   help = 'run in batch mode for one second',
+                   )
+options.add_option('-l', '--log',
+                   action = 'store_true',
+                   default = False,
+                   dest = 'log',
+                   help = 'run in logging mode (like vmstat)',
+                   )
+options.add_option('-f', '--fields',
+                   action = 'store',
+                   default = None,
+                   dest = 'fields',
+                   help = 'fields to display (regex)',
+                   )
+(options, args) = options.parse_args(sys.argv)
+
+try:
+    provider = TracepointProvider()
+except:
+    provider = DebugfsProvider()
+
+stats = Stats(provider, fields = options.fields)
+
+if options.log:
+    log(stats)
+elif not options.once:
+    import curses.wrapper
+    curses.wrapper(tui, stats)
+else:
+    batch(stats)