cpu: Get rid of the nextInstEventCount method.

This was only used by the KVM CPU, and it has access to all it needs to
figure out that value locally without requiring all the ThreadContexts
to implement an equivalent function.

Change-Id: I17a14ce669db2519edf129db761ebd8dc3bd4129
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22114
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

6 files changed, 6 insertions, 23 deletions

diff --git a/src/arch/arm/fastmodel/iris/thread_context.hh b/src/arch/arm/fastmodel/iris/thread_context.hh
index ef5214333..acb325cdb 100644
--- a/src/arch/arm/fastmodel/iris/thread_context.hh
+++ b/src/arch/arm/fastmodel/iris/thread_context.hh
@@ -96,7 +96,6 @@ class ThreadContext : public ::ThreadContext
     bool schedule(PCEvent *e) override { return false; }
     bool remove(PCEvent *e) override { return false; }
 
-    Tick nextInstEventCount() override { return MaxTick; }
     void scheduleInstCountEvent(Event *event, Tick count) override {}
     void descheduleInstCountEvent(Event *event) override {}
     Tick getCurrentInstCount() override;
diff --git a/src/cpu/checker/thread_context.hh b/src/cpu/checker/thread_context.hh
index d32e0fa70..347c4bab6 100644
--- a/src/cpu/checker/thread_context.hh
+++ b/src/cpu/checker/thread_context.hh
@@ -92,11 +92,6 @@ class CheckerThreadContext : public ThreadContext
     bool schedule(PCEvent *e) override { return actualTC->schedule(e); }
     bool remove(PCEvent *e) override { return actualTC->remove(e); }
 
-    Tick
-    nextInstEventCount() override
-    {
-        return actualTC->nextInstEventCount();
-    }
     void
     scheduleInstCountEvent(Event *event, Tick count) override
     {
diff --git a/src/cpu/kvm/base.cc b/src/cpu/kvm/base.cc
index 2522eeeb2..83cb04f47 100644
--- a/src/cpu/kvm/base.cc
+++ b/src/cpu/kvm/base.cc
@@ -630,7 +630,9 @@ BaseKvmCPU::tick()
 
       case RunningServiceCompletion:
       case Running: {
-          const uint64_t nextInstEvent(tc->nextInstEventCount());
+          auto &queue = thread->comInstEventQueue;
+          const uint64_t nextInstEvent(
+                  queue.empty() ? MaxTick : queue.nextTick());
           // Enter into KVM and complete pending IO instructions if we
           // have an instruction event pending.
           const Tick ticksToExecute(
@@ -686,7 +688,7 @@ BaseKvmCPU::tick()
           // Service any pending instruction events. The vCPU should
           // have exited in time for the event using the instruction
           // counter configured by setupInstStop().
-          thread->comInstEventQueue.serviceEvents(ctrInsts);
+          queue.serviceEvents(ctrInsts);
 
           if (tryDrain())
               _status = Idle;
@@ -1346,10 +1348,10 @@ BaseKvmCPU::ioctlRun()
 void
 BaseKvmCPU::setupInstStop()
 {
-    Tick next = tc->nextInstEventCount();
-    if (next == MaxTick) {
+    if (thread->comInstEventQueue.empty()) {
         setupInstCounter(0);
     } else {
+        Tick next = thread->comInstEventQueue.nextTick();
         assert(next > ctrInsts);
         setupInstCounter(next - ctrInsts);
     }
diff --git a/src/cpu/o3/thread_context.hh b/src/cpu/o3/thread_context.hh
index 65496429b..c68f34c07 100644
--- a/src/cpu/o3/thread_context.hh
+++ b/src/cpu/o3/thread_context.hh
@@ -86,12 +86,6 @@ class O3ThreadContext : public ThreadContext
         return thread->pcEventQueue.remove(e);
     }
 
-    Tick
-    nextInstEventCount() override
-    {
-        return thread->comInstEventQueue.empty() ?
-            MaxTick : thread->comInstEventQueue.nextTick();
-    }
     void
     scheduleInstCountEvent(Event *event, Tick count) override
     {
diff --git a/src/cpu/simple_thread.hh b/src/cpu/simple_thread.hh
index 367eceab3..3a7c85a90 100644
--- a/src/cpu/simple_thread.hh
+++ b/src/cpu/simple_thread.hh
@@ -198,12 +198,6 @@ class SimpleThread : public ThreadState, public ThreadContext
     bool schedule(PCEvent *e) override { return pcEventQueue.schedule(e); }
     bool remove(PCEvent *e) override { return pcEventQueue.remove(e); }
 
-    Tick
-    nextInstEventCount() override
-    {
-        return comInstEventQueue.empty() ?
-            MaxTick : comInstEventQueue.nextTick();
-    }
     void
     scheduleInstCountEvent(Event *event, Tick count) override
     {
diff --git a/src/cpu/thread_context.hh b/src/cpu/thread_context.hh
index 2e1b572e6..a77ac4848 100644
--- a/src/cpu/thread_context.hh
+++ b/src/cpu/thread_context.hh
@@ -192,7 +192,6 @@ class ThreadContext : public PCEventScope
 
     virtual EndQuiesceEvent *getQuiesceEvent() = 0;
 
-    virtual Tick nextInstEventCount() = 0;
     virtual void scheduleInstCountEvent(Event *event, Tick count) = 0;
     virtual void descheduleInstCountEvent(Event *event) = 0;
     virtual Tick getCurrentInstCount() = 0;