It might be handy to display the full history of event stats in some cases.
Since we have that available for debugfs, we offer a respective command to
display what's available.
Note that this command does not toggle - one merely has to reset the stats
via 'r' to do the next best thing to reverting the effect of 't'.
Signed-off-by: Stefan Raspl <raspl@xxxxxxxxxxxxxxxxxx>
---
tools/kvm/kvm_stat/kvm_stat | 38 ++++++++++++++++++++++++++++++++++++--
tools/kvm/kvm_stat/kvm_stat.txt | 2 ++
2 files changed, 38 insertions(+), 2 deletions(-)
diff --git a/tools/kvm/kvm_stat/kvm_stat b/tools/kvm/kvm_stat/kvm_stat
index 1276b88937c0..169f6601a90c 100755
--- a/tools/kvm/kvm_stat/kvm_stat
+++ b/tools/kvm/kvm_stat/kvm_stat
@@ -677,6 +677,10 @@ class TracepointProvider(Provider):
for event in group.events:
event.reset()
+ def restore(self):
+ """No historic data available that we could restore"""
+ pass
+
class DebugfsProvider(Provider):
"""Provides data from the files that KVM creates in the kvm debugfs
@@ -730,7 +734,14 @@ class DebugfsProvider(Provider):
self.reset()
def read(self, reset=0):
- """Returns a dict with format:'file name / field -> current value'."""
+ """Returns a dict with format:'file name / field -> current value'.
+
+ Parameter 'reset':
+ 0 plain read
+ 1 reset field counts to 0
+ 2 restore the original field counts
+
+ """
results = {}
# If no debugfs filtering support is available, then don't read.
@@ -747,8 +758,10 @@ class DebugfsProvider(Provider):
for field in self._fields:
value = self.read_field(field, path)
key = path + field
- if reset:
+ if reset == 1:
self._baseline[key] = value
+ if reset == 2:
+ self._baseline[key] = 0
if self._baseline.get(key, -1) == -1:
self._baseline[key] = value
results[field] = (results.get(field, 0) + value -
@@ -771,6 +784,11 @@ class DebugfsProvider(Provider):
self._baseline = {}
self.read(1)
+ def restore(self):
+ """Reset field counters"""
+ self._baseline = {}
+ self.read(2)
+
class Stats(object):
"""Manages the data providers and the data they provide.
@@ -806,10 +824,20 @@ class Stats(object):
provider.update_fields(self._fields_filter)
def reset(self):
+ """Reset providers' field counters"""
self.values = {}
for provider in self.providers:
provider.reset()
+ def restore(self):
+ """Restore providers' field counters"""
+ self.values = {}
+ for provider in self.providers:
+ provider.restore()
+ # Updates oldval (see get()) for all fields to prevent the totals from
+ # being displayed in the 'CurAvg/s' column on next refresh
+ self.get()
+
@property
def fields_filter(self):
return self._fields_filter
@@ -1029,6 +1057,7 @@ class Tui(object):
' q quit',
' r reset stats',
' s set update interval',
+ ' t show total available stats (debugfs only)',
' x toggle reporting of stats for individual child trace'
' events',
'Any other key refreshes statistics immediately')
@@ -1229,8 +1258,12 @@ class Tui(object):
self.show_set_update_interval()
curses.curs_set(0)
sleeptime = self._delay_initial
+ if char == 't':
+ self.stats.restore()
if char == 'x':
self.update_drilldown()
+ # prevents display of current values on next refresh
+ self.stats.get()
except KeyboardInterrupt:
break
except curses.error:
@@ -1306,6 +1339,7 @@ Interactive Commands:
q quit
r reset stats
s set update interval
+ t show total available stats (debugfs only)
x toggle reporting of stats for individual child trace events
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 cc019b09e0f5..53478ff6eded 100644
--- a/tools/kvm/kvm_stat/kvm_stat.txt
+++ b/tools/kvm/kvm_stat/kvm_stat.txt
@@ -45,6 +45,8 @@ INTERACTIVE COMMANDS
*s*:: set update interval
+*t*:: show total available stats (debugfs only)
+
*x*:: toggle reporting of stats for child trace events
Press any other key to refresh statistics immediately.
--
2.11.2
