From d4525d7460d6d129d3a6e4b94a125afb6a06e6ca Mon Sep 17 00:00:00 2001
From: David Hildenbrand <david@redhat.com>
Date: Tue, 17 Oct 2017 19:15:31 +0200
Subject: [PATCH 26/69] tools/kvm_stat: fix trace setup glitch on field updates
 in TracepointProvider
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RH-Author: David Hildenbrand <david@redhat.com>
Message-id: <20171017191605.2378-6-david@redhat.com>
Patchwork-id: 77316
O-Subject: [RHEL-7.5 qemu-kvm-rhev PATCH 05/39] tools/kvm_stat: fix trace setup glitch on field updates in TracepointProvider
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 a183606937489ab5ada2215aa8211374a6b26bd3

commit a183606937489ab5ada2215aa8211374a6b26bd3
Author: Stefan Raspl <raspl@linux.vnet.ibm.com>
Date:   Fri Mar 10 13:40:04 2017 +0100

    tools/kvm_stat: fix trace setup glitch on field updates in TracepointProvider

    Updating the fields of the TracepointProvider does not propagate changes to the
    tracepoints. This shows when a pid filter is enabled, whereby subsequent
    extensions of the fields of the Tracepoint provider (e.g. by toggling
    drilldown) will not modify the tracepoints as required.
    To reproduce, select a specific process via interactive command 'p', and
    enable drilldown via 'x' - none of the fields with the braces will appear
    although they should.
    The fix will always leave all available fields in the TracepointProvider
    enabled.

    Signed-off-by: Stefan Raspl <raspl@linux.vnet.ibm.com>
    Based-on-text-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 | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/scripts/kvm/kvm_stat b/scripts/kvm/kvm_stat
index 231186a..6207843 100755
--- a/scripts/kvm/kvm_stat
+++ b/scripts/kvm/kvm_stat
@@ -550,6 +550,7 @@ class TracepointProvider(object):
     def setup_traces(self):
         """Creates all event and group objects needed to be able to retrieve
         data."""
+        fields = self.get_available_fields()
         if self._pid > 0:
             # Fetch list of all threads of the monitored pid, as qemu
             # starts a thread for each vcpu.
@@ -560,7 +561,7 @@ class TracepointProvider(object):
 
         # The constant is needed as a buffer for python libs, std
         # streams and other files that the script opens.
-        newlim = len(groupids) * len(self._fields) + 50
+        newlim = len(groupids) * len(fields) + 50
         try:
             softlim_, hardlim = resource.getrlimit(resource.RLIMIT_NOFILE)
 
@@ -576,7 +577,7 @@ class TracepointProvider(object):
 
         for groupid in groupids:
             group = Group()
-            for name in self._fields:
+            for name in fields:
                 tracepoint = name
                 tracefilter = None
                 match = re.match(r'(.*)\((.*)\)', name)
-- 
1.8.3.1