From 243d90a041dca861bb85bc71df863578a8f839bd Mon Sep 17 00:00:00 2001

From: David Hildenbrand <david@redhat.com>

Date: Tue, 17 Oct 2017 19:15:42 +0200

Subject: [PATCH 37/69] tools/kvm_stat: add interactive command 'r'

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RH-Author: David Hildenbrand <david@redhat.com>

Message-id: <20171017191605.2378-17-david@redhat.com>

Patchwork-id: 77326

O-Subject: [RHEL-7.5 qemu-kvm-rhev PATCH 16/39] tools/kvm_stat: add interactive command 'r'

Bugzilla: 1497137

RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>

RH-Acked-by: Cornelia Huck <cohuck@redhat.com>

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

RH-Acked-by: Thomas Huth <thuth@redhat.com>

Upstream-status: linux.git 9f114a03c6854f49065dd036c17e1b4bb947f842

Convertion of documentation (for man page generation) to texi.

commit 9f114a03c6854f49065dd036c17e1b4bb947f842

Author: Stefan Raspl <raspl@linux.vnet.ibm.com>

Date:   Fri Mar 10 13:40:15 2017 +0100

    tools/kvm_stat: add interactive command 'r'

    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 <raspl@linux.vnet.ibm.com>

    Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com>

    Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

Signed-off-by: David Hildenbrand <david@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 scripts/kvm/kvm_stat      | 65 +++++++++++++++++++++++++++++++++++++----------

 scripts/kvm/kvm_stat.texi |  3 +++

 2 files changed, 54 insertions(+), 14 deletions(-)

diff --git a/scripts/kvm/kvm_stat b/scripts/kvm/kvm_stat

index 676a92a..f8c48f8 100755

--- a/scripts/kvm/kvm_stat

+++ b/scripts/kvm/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/scripts/kvm/kvm_stat.texi b/scripts/kvm/kvm_stat.texi

index 203d61d..c0cb7bc 100644

--- a/scripts/kvm/kvm_stat.texi

+++ b/scripts/kvm/kvm_stat.texi

@@ -39,6 +39,9 @@ filter by PID

 @item q

 @kindex q

 quit

+@item r

+@kindex r

+reset stats

 @item x

 @kindex x

 toggle reporting of stats for child trace events

-- 

1.8.3.1