From 9f114a03c6854f49065dd036c17e1b4bb947f842 Mon Sep 17 00:00:00 2001 From: Stefan Raspl Date: Fri, 10 Mar 2017 13:40:15 +0100 Subject: [PATCH] tools/kvm_stat: add interactive command 'r' MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Provide an interactive command to reset the tracepoint statistics. Requires some extra work for debugfs, as the counters cannot be reset. On the up side, this offers us the opportunity to have debugfs values reset on startup and whenever a filter is modified, becoming consistent with the tracepoint provider. As a bonus, 'kvmstat -dt' will now provide useful output, instead of mixing values in totally different orders of magnitude. Furthermore, we avoid unnecessary resets when any of the filters is "changed" interactively to the previous value. Signed-off-by: Stefan Raspl Acked-by: Janosch Frank Signed-off-by: Radim Krčmář --- tools/kvm/kvm_stat/kvm_stat | 65 ++++++++++++++++++++++++++------- tools/kvm/kvm_stat/kvm_stat.txt | 2 + 2 files changed, 53 insertions(+), 14 deletions(-) diff --git a/tools/kvm/kvm_stat/kvm_stat b/tools/kvm/kvm_stat/kvm_stat index 676a92a4a12e..f8c48f8d07a7 100755 --- a/tools/kvm/kvm_stat/kvm_stat +++ b/tools/kvm/kvm_stat/kvm_stat @@ -716,15 +716,23 @@ class TracepointProvider(object): ret[name] += val return ret + def reset(self): + """Reset all field counters""" + for group in self.group_leaders: + for event in group.events: + event.reset() + class DebugfsProvider(object): """Provides data from the files that KVM creates in the kvm debugfs folder.""" def __init__(self): self._fields = self.get_available_fields() + self._baseline = {} self._pid = 0 self.do_read = True self.paths = [] + self.reset() def get_available_fields(self): """"Returns a list of available fields. @@ -741,6 +749,7 @@ class DebugfsProvider(object): @fields.setter def fields(self, fields): self._fields = fields + self.reset() @property def pid(self): @@ -758,10 +767,11 @@ class DebugfsProvider(object): self.paths = filter(lambda x: "{}-".format(pid) in x, vms) else: - self.paths = [''] + self.paths = [] self.do_read = True + self.reset() - def read(self): + def read(self, reset=0): """Returns a dict with format:'file name / field -> current value'.""" results = {} @@ -769,10 +779,22 @@ class DebugfsProvider(object): if not self.do_read: return results - for path in self.paths: + paths = self.paths + if self._pid == 0: + paths = [] + for entry in os.walk(PATH_DEBUGFS_KVM): + for dir in entry[1]: + paths.append(dir) + for path in paths: for field in self._fields: - results[field] = results.get(field, 0) \ - + self.read_field(field, path) + value = self.read_field(field, path) + key = path + field + if reset: + self._baseline[key] = value + if self._baseline.get(key, -1) == -1: + self._baseline[key] = value + results[field] = (results.get(field, 0) + value - + self._baseline.get(key, 0)) return results @@ -786,6 +808,11 @@ class DebugfsProvider(object): except IOError: return 0 + def reset(self): + """Reset field counters""" + self._baseline = {} + self.read(1) + class Stats(object): """Manages the data providers and the data they provide. @@ -822,14 +849,20 @@ class Stats(object): for provider in self.providers: provider.pid = self._pid_filter + def reset(self): + self.values = {} + for provider in self.providers: + provider.reset() + @property def fields_filter(self): return self._fields_filter @fields_filter.setter def fields_filter(self, fields_filter): - self._fields_filter = fields_filter - self.update_provider_filters() + if fields_filter != self._fields_filter: + self._fields_filter = fields_filter + self.update_provider_filters() @property def pid_filter(self): @@ -837,9 +870,10 @@ class Stats(object): @pid_filter.setter def pid_filter(self, pid): - self._pid_filter = pid - self.values = {} - self.update_provider_pid() + if pid != self._pid_filter: + self._pid_filter = pid + self.values = {} + self.update_provider_pid() def get(self): """Returns a dict with field -> (value, delta to last value) of all @@ -847,11 +881,9 @@ class Stats(object): for provider in self.providers: new = provider.read() for key in provider.fields: - oldval = self.values.get(key, (0, 0)) + oldval = self.values.get(key, (0, 0))[0] newval = new.get(key, 0) - newdelta = None - if oldval is not None: - newdelta = newval - oldval[0] + newdelta = newval - oldval self.values[key] = (newval, newdelta) return self.values @@ -1117,6 +1149,10 @@ class Tui(object): if char == 'p': self.show_vm_selection_by_pid() sleeptime = DELAY_INITIAL + if char == 'r': + self.refresh_header() + self.stats.reset() + sleeptime = DELAY_INITIAL except KeyboardInterrupt: break except curses.error: @@ -1190,6 +1226,7 @@ Interactive Commands: p filter by PID q quit x toggle reporting of stats for individual child trace events + r reset stats Press any other key to refresh statistics immediately. """ diff --git a/tools/kvm/kvm_stat/kvm_stat.txt b/tools/kvm/kvm_stat/kvm_stat.txt index c3ab6a2c8c37..109431bdc63c 100644 --- a/tools/kvm/kvm_stat/kvm_stat.txt +++ b/tools/kvm/kvm_stat/kvm_stat.txt @@ -39,6 +39,8 @@ INTERACTIVE COMMANDS *q*:: quit +*r*:: reset stats + *x*:: toggle reporting of stats for child trace events Press any other key to refresh statistics immediately. -- 2.20.1