From d895493b7c8bf22305ebcf74b3e64d1d12e4d27f Mon Sep 17 00:00:00 2001 From: Janosch Frank Date: Mon, 11 Jan 2016 16:17:54 +0100 Subject: [PATCH] scripts/kvm/kvm_stat: Cleanup of Event class Added additional newlines for readability. Factored out attribute and event setup code into own methods. Exchanged file() with preferred open(). Signed-off-by: Janosch Frank Message-Id: <1452525484-32309-25-git-send-email-frankja@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini --- scripts/kvm/kvm_stat | 67 +++++++++++++++++++++++++++++++++------------------- 1 file changed, 43 insertions(+), 24 deletions(-) diff --git a/scripts/kvm/kvm_stat b/scripts/kvm/kvm_stat index 91054e5efa..bf948b9cc0 100755 --- a/scripts/kvm/kvm_stat +++ b/scripts/kvm/kvm_stat @@ -339,15 +339,11 @@ PATH_DEBUGFS_TRACING = '/sys/kernel/debug/tracing' PATH_DEBUGFS_KVM = '/sys/kernel/debug/kvm' class Group(object): - def __init__(self, cpu): + def __init__(self): self.events = [] - self.cpu = cpu - def add_event(self, name, event_set, tracepoint, tracefilter=None): - self.events.append(Event(group=self, - name=name, event_set=event_set, - tracepoint=tracepoint, - tracefilter=tracefilter)) + def add_event(self, event): + self.events.append(event) def read(self): length = 8 * (1 + len(self.events)) @@ -357,32 +353,52 @@ class Group(object): os.read(self.events[0].fd, length)))) class Event(object): - def __init__(self, group, name, event_set, tracepoint, tracefilter=None): + def __init__(self, name, group, trace_cpu, trace_point, trace_filter, + trace_set='kvm'): self.name = name - attr = perf_event_attr() - attr.type = PERF_TYPE_TRACEPOINT - attr.size = ctypes.sizeof(attr) - id_path = os.path.join(PATH_DEBUGFS_TRACING, 'events', event_set, - tracepoint, 'id') - id = int(file(id_path).read()) - attr.config = id - attr.sample_period = 1 - attr.read_format = PERF_FORMAT_GROUP + self.fd = None + self.setup_event(group, trace_cpu, trace_point, trace_filter, + trace_set) + + def setup_event_attribute(self, trace_set, trace_point): + id_path = os.path.join(PATH_DEBUGFS_TRACING, 'events', trace_set, + trace_point, 'id') + + event_attr = perf_event_attr() + event_attr.type = PERF_TYPE_TRACEPOINT + event_attr.size = ctypes.sizeof(event_attr) + event_attr.config = int(open(id_path).read()) + event_attr.sample_period = 1 + event_attr.read_format = PERF_FORMAT_GROUP + return event_attr + + def setup_event(self, group, trace_cpu, trace_point, trace_filter, + trace_set): + event_attr = self.setup_event_attribute(trace_set, trace_point) + group_leader = -1 if group.events: group_leader = group.events[0].fd - fd = perf_event_open(attr, -1, group.cpu, group_leader, 0) + + fd = perf_event_open(event_attr, -1, trace_cpu, + group_leader, 0) if fd == -1: err = ctypes.get_errno() raise OSError(err, os.strerror(err), 'while calling sys_perf_event_open().') - if tracefilter: - fcntl.ioctl(fd, IOCTL_NUMBERS['SET_FILTER'], tracefilter) + + if trace_filter: + fcntl.ioctl(fd, IOCTL_NUMBERS['SET_FILTER'], + trace_filter) + self.fd = fd + def enable(self): fcntl.ioctl(self.fd, IOCTL_NUMBERS['ENABLE'], 0) + def disable(self): fcntl.ioctl(self.fd, IOCTL_NUMBERS['DISABLE'], 0) + def reset(self): fcntl.ioctl(self.fd, IOCTL_NUMBERS['RESET'], 0) @@ -418,7 +434,7 @@ class TracepointProvider(object): sys.exit("NOFILE rlimit could not be raised to {0}".format(rlimit)) for cpu in cpus: - group = Group(cpu) + group = Group() for name in self._fields: tracepoint = name tracefilter = None @@ -428,9 +444,12 @@ class TracepointProvider(object): tracefilter = ('%s==%d\0' % (self.filters[tracepoint][0], self.filters[tracepoint][1][sub])) - group.add_event(name, event_set='kvm', - tracepoint=tracepoint, - tracefilter=tracefilter) + + group.add_event(Event(name=name, + group=group, + trace_cpu=cpu, + trace_point=tracepoint, + trace_filter=tracefilter)) self.group_leaders.append(group) @property -- 2.11.4.GIT