From df059f45a0cbd230ad00f6da24cfc5d228430e16 Mon Sep 17 00:00:00 2001
From: Andreas Sandberg <andreas@sandberg.pp.se>
Date: Tue, 11 Jun 2013 09:24:40 +0200
Subject: [PATCH] kvm: Maintain a local instruction counter and update
 totalNumInsts

Update the system's totalNumInst counter when exiting from KVM and
maintain an internal absolute instruction count instead of relying on
the one from perf.
---
 src/cpu/kvm/base.cc | 9 ++++++---
 src/cpu/kvm/base.hh | 3 +++
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/cpu/kvm/base.cc b/src/cpu/kvm/base.cc
index a0aa511ea..6ffad82d7 100644
--- a/src/cpu/kvm/base.cc
+++ b/src/cpu/kvm/base.cc
@@ -80,7 +80,8 @@ BaseKvmCPU::BaseKvmCPU(BaseKvmCPUParams *params)
       pageSize(sysconf(_SC_PAGE_SIZE)),
       tickEvent(*this),
       perfControlledByTimer(params->usePerfOverflow),
-      hostFactor(params->hostFactor)
+      hostFactor(params->hostFactor),
+      ctrInsts(0)
 {
     if (pageSize == -1)
         panic("KVM: Failed to determine host page size (%i)\n",
@@ -416,14 +417,14 @@ BaseKvmCPU::getContext(int tn)
 Counter
 BaseKvmCPU::totalInsts() const
 {
-    return hwInstructions.read();
+    return ctrInsts;
 }
 
 Counter
 BaseKvmCPU::totalOps() const
 {
     hack_once("Pretending totalOps is equivalent to totalInsts()\n");
-    return hwInstructions.read();
+    return ctrInsts;
 }
 
 void
@@ -522,6 +523,8 @@ BaseKvmCPU::kvmRun(Tick ticks)
     numCycles += simCyclesExecuted;;
     ++numVMExits;
     numInsts += instsExecuted;
+    ctrInsts += instsExecuted;
+    system->totalNumInsts += instsExecuted;
 
     DPRINTF(KvmRun, "KVM: Executed %i instructions in %i cycles (%i ticks, sim cycles: %i).\n",
             instsExecuted, hostCyclesExecuted, ticksExecuted, simCyclesExecuted);
diff --git a/src/cpu/kvm/base.hh b/src/cpu/kvm/base.hh
index c53f715e3..81b24a378 100644
--- a/src/cpu/kvm/base.hh
+++ b/src/cpu/kvm/base.hh
@@ -561,6 +561,9 @@ class BaseKvmCPU : public BaseCPU
     Stats::Scalar numInterrupts;
     Stats::Scalar numHypercalls;
     /* @} */
+
+    /** Number of instructions executed by the CPU */
+    Counter ctrInsts;
 };
 
 #endif
-- 
2.30.2