From: Stefan Raspl <stefan.raspl@de.ibm.com>
Date: Mon, 5 Feb 2018 12:59:57 +0000 (+0100)
Subject: tools/kvm_stat: fix crash when filtering out all non-child trace events
X-Git-Tag: v4.16-rc4~38^2~17
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3df33a0f34a3883b6696bff8cc8fcda3c7444a62;p=thirdparty%2Fkernel%2Flinux.git

tools/kvm_stat: fix crash when filtering out all non-child trace events

When we apply a filter that will only leave child trace events, we
receive a ZeroDivisionError when calculating the percentages.
In that case, provide percentages based on child events only.
To reproduce, run 'kvm_stat -f .*[\(].*'.

Signed-off-by: Stefan Raspl <raspl@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---

diff --git a/tools/kvm/kvm_stat/kvm_stat b/tools/kvm/kvm_stat/kvm_stat
index e3f0becb6632e..4e0f282c52896 100755
--- a/tools/kvm/kvm_stat/kvm_stat
+++ b/tools/kvm/kvm_stat/kvm_stat
@@ -1084,9 +1084,15 @@ class Tui(object):
         self.screen.clrtobot()
         stats = self.stats.get(self._display_guests)
         total = 0.
+        ctotal = 0.
         for key, values in stats.items():
             if key.find('(') == -1:
                 total += values.value
+            else:
+                ctotal += values.value
+        if total == 0.:
+            # we don't have any fields, or all non-child events are filtered
+            total = ctotal
 
         if self._sorting == SORT_DEFAULT:
             def sortkey((_k, v)):