arch: cpu: Track kernel stats using the base ISA agnostic type.

Then cast to the ISA specific type when necessary. This removes
(mostly) an ISA specific aspect to some of the interfaces. The ISA
specific version of the kernel stats still needs to be constructed and
stored in a few places which means that kernel_stats.hh still needs to
be a switching arch header, for instance.

In the future, I'd like to make the kernel its own object like the
Process objects in SE mode, and then it would be able to instantiate
and maintain its own stats.

Change-Id: I8309d49019124f6bea1482aaea5b5b34e8c97433
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18429
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

src/arch/alpha/ev5.cc

@@ -219,6 +219,9 @@ int break_ipl = -1;
 void
 ISA::setIpr(int idx, uint64_t val, ThreadContext *tc)
 {
+    auto *stats = dynamic_cast<AlphaISA::Kernel::Statistics *>(
+            tc->getKernelStats());
+    assert(stats || !tc->getKernelStats());
     switch (idx) {
       case IPR_PALtemp0:
       case IPR_PALtemp1:
@@ -267,8 +270,8 @@ ISA::setIpr(int idx, uint64_t val, ThreadContext *tc)
 
       case IPR_PALtemp23:
         // write entire quad w/ no side-effect
-        if (tc->getKernelStats())
-            tc->getKernelStats()->context(ipr[idx], val, tc);
+        if (stats)
+            stats->context(ipr[idx], val, tc);
         ipr[idx] = val;
         break;
 
@@ -291,17 +294,17 @@ ISA::setIpr(int idx, uint64_t val, ThreadContext *tc)
       case IPR_IPLR:
         // only write least significant five bits - interrupt level
         ipr[idx] = val & 0x1f;
-        if (tc->getKernelStats())
-            tc->getKernelStats()->swpipl(ipr[idx]);
+        if (stats)
+            stats->swpipl(ipr[idx]);
         break;
 
       case IPR_DTB_CM:
         if (val & 0x18) {
-            if (tc->getKernelStats())
-                tc->getKernelStats()->mode(Kernel::user, tc);
+            if (stats)
+                stats->mode(Kernel::user, tc);
         } else {
-            if (tc->getKernelStats())
-                tc->getKernelStats()->mode(Kernel::kernel, tc);
+            if (stats)
+                stats->mode(Kernel::kernel, tc);
         }
         M5_FALLTHROUGH;
 
@@ -485,6 +488,9 @@ using namespace AlphaISA;
 Fault
 SimpleThread::hwrei()
 {
+    auto *stats = dynamic_cast<AlphaISA::Kernel::Statistics *>(kernelStats);
+    assert(stats || !kernelStats);
+
     PCState pc = pcState();
     if (!(pc.pc() & 0x3))
         return std::make_shared<UnimplementedOpcodeFault>();
@@ -494,8 +500,8 @@ SimpleThread::hwrei()
 
     CPA::cpa()->swAutoBegin(this, pc.npc());
 
-    if (kernelStats)
-        kernelStats->hwrei();
+    if (stats)
+        stats->hwrei();
 
     // FIXME: XXX check for interrupts? XXX
     return NoFault;
@@ -508,8 +514,11 @@ SimpleThread::hwrei()
 bool
 SimpleThread::simPalCheck(int palFunc)
 {
-    if (kernelStats)
-        kernelStats->callpal(palFunc, this);
+    auto *stats = dynamic_cast<AlphaISA::Kernel::Statistics *>(kernelStats);
+    assert(stats || !kernelStats);
+
+    if (stats)
+        stats->callpal(palFunc, this);
 
     switch (palFunc) {
       case PAL::halt:

src/arch/alpha/idle_event.cc

@@ -41,7 +41,10 @@ IdleStartEvent::process(ThreadContext *tc)
 {
     if (tc->getKernelStats()) {
         RegVal val = tc->readMiscRegNoEffect(IPR_PALtemp23);
-        tc->getKernelStats()->setIdleProcess(val, tc);
+        auto *stats = dynamic_cast<AlphaISA::Kernel::Statistics *>(
+                tc->getKernelStats());
+        assert(stats);
+        stats->setIdleProcess(val, tc);
     }
     remove();
 }

src/cpu/checker/cpu.cc

@@ -47,7 +47,6 @@
 #include <string>
 
 #include "arch/generic/tlb.hh"
-#include "arch/kernel_stats.hh"
 #include "arch/vtophys.hh"
 #include "cpu/base.hh"
 #include "cpu/simple_thread.hh"

src/cpu/checker/thread_context.hh

@@ -52,10 +52,10 @@
 #include "debug/Checker.hh"
 
 class EndQuiesceEvent;
+namespace Kernel {
+    class Statistics;
+};
 namespace TheISA {
-    namespace Kernel {
-        class Statistics;
-    };
     class Decoder;
 };
 
@@ -134,7 +134,7 @@ class CheckerThreadContext : public ThreadContext
 
     System *getSystemPtr() override { return actualTC->getSystemPtr(); }
 
-    TheISA::Kernel::Statistics *
+    ::Kernel::Statistics *
     getKernelStats() override
     {
         return actualTC->getKernelStats();

src/cpu/o3/cpu.cc

@@ -925,7 +925,10 @@ FullO3CPU<Impl>::hwrei(ThreadID tid)
     // Need to clear the lock flag upon returning from an interrupt.
     this->setMiscRegNoEffect(AlphaISA::MISCREG_LOCKFLAG, false, tid);
 
-    this->thread[tid]->kernelStats->hwrei();
+    auto *stats = dynamic_cast<AlphaISA::Kernel::Statistics *>(
+            this->thread[tid]->kernelStats);
+    assert(stats);
+    stats->hwrei();
 
     // FIXME: XXX check for interrupts? XXX
 #endif
@@ -937,9 +940,10 @@ bool
 FullO3CPU<Impl>::simPalCheck(int palFunc, ThreadID tid)
 {
 #if THE_ISA == ALPHA_ISA
-    if (this->thread[tid]->kernelStats)
-        this->thread[tid]->kernelStats->callpal(palFunc,
-                                                this->threadContexts[tid]);
+    auto *stats = dynamic_cast<AlphaISA::Kernel::Statistics *>(
+            this->thread[tid]->kernelStats);
+    if (stats)
+        stats->callpal(palFunc, this->threadContexts[tid]);
 
     switch (palFunc) {
       case PAL::halt:

src/cpu/o3/regfile.hh

@@ -48,7 +48,6 @@
 #include <vector>
 
 #include "arch/isa_traits.hh"
-#include "arch/kernel_stats.hh"
 #include "arch/types.hh"
 #include "base/trace.hh"
 #include "config/the_isa.hh"

src/cpu/o3/thread_context.hh

@@ -119,7 +119,7 @@ class O3ThreadContext : public ThreadContext
     System *getSystemPtr() override { return cpu->system; }
 
     /** Returns a pointer to this thread's kernel statistics. */
-    TheISA::Kernel::Statistics *
+    ::Kernel::Statistics *
     getKernelStats() override
     {
         return thread->kernelStats;

src/cpu/simple/base.cc

@@ -43,7 +43,6 @@
 
 #include "cpu/simple/base.hh"
 
-#include "arch/kernel_stats.hh"
 #include "arch/stacktrace.hh"
 #include "arch/utility.hh"
 #include "arch/vtophys.hh"

src/cpu/simple_thread.hh

@@ -74,10 +74,8 @@ class CheckerCPU;
 class FunctionProfile;
 class ProfileNode;
 
-namespace TheISA {
-    namespace Kernel {
-        class Statistics;
-    }
+namespace Kernel {
+    class Statistics;
 }
 
 /**
@@ -212,7 +210,7 @@ class SimpleThread : public ThreadState, public ThreadContext
 
     System *getSystemPtr() override { return system; }
 
-    TheISA::Kernel::Statistics *
+    Kernel::Statistics *
     getKernelStats() override
     {
         return ThreadState::getKernelStats();

src/cpu/thread_context.cc

@@ -44,7 +44,6 @@
 #include "cpu/thread_context.hh"
 
 #include "arch/generic/vec_pred_reg.hh"
-#include "arch/kernel_stats.hh"
 #include "base/logging.hh"
 #include "base/trace.hh"
 #include "config/the_isa.hh"
@@ -52,6 +51,7 @@
 #include "cpu/quiesce_event.hh"
 #include "debug/Context.hh"
 #include "debug/Quiesce.hh"
+#include "kern/kernel_stats.hh"
 #include "params/BaseCPU.hh"
 #include "sim/full_system.hh"
 
@@ -139,7 +139,7 @@ ThreadContext::quiesce()
 
     suspend();
     if (getKernelStats())
-       getKernelStats()->quiesce();
+        getKernelStats()->quiesce();
 }
 
 

src/cpu/thread_context.hh

@@ -70,10 +70,8 @@ class FSTranslatingPortProxy;
 class PortProxy;
 class Process;
 class System;
-namespace TheISA {
-    namespace Kernel {
-        class Statistics;
-    }
+namespace Kernel {
+    class Statistics;
 }
 
 /**
@@ -150,7 +148,7 @@ class ThreadContext
 
     virtual System *getSystemPtr() = 0;
 
-    virtual TheISA::Kernel::Statistics *getKernelStats() = 0;
+    virtual ::Kernel::Statistics *getKernelStats() = 0;
 
     virtual PortProxy &getPhysProxy() = 0;
 

src/cpu/thread_state.cc

@@ -30,11 +30,11 @@
 
 #include "cpu/thread_state.hh"
 
-#include "arch/kernel_stats.hh"
 #include "base/output.hh"
 #include "cpu/base.hh"
 #include "cpu/profile.hh"
 #include "cpu/quiesce_event.hh"
+#include "kern/kernel_stats.hh"
 #include "mem/fs_translating_port_proxy.hh"
 #include "mem/port.hh"
 #include "mem/port_proxy.hh"

src/cpu/thread_state.hh

@@ -41,10 +41,8 @@
 class EndQuiesceEvent;
 class FunctionProfile;
 class ProfileNode;
-namespace TheISA {
-    namespace Kernel {
-        class Statistics;
-    }
+namespace Kernel {
+    class Statistics;
 }
 
 class Checkpoint;
@@ -98,7 +96,7 @@ struct ThreadState : public Serializable {
 
     void profileSample();
 
-    TheISA::Kernel::Statistics *getKernelStats() { return kernelStats; }
+    Kernel::Statistics *getKernelStats() { return kernelStats; }
 
     PortProxy &getPhysProxy();
 
@@ -185,7 +183,7 @@ struct ThreadState : public Serializable {
     Addr profilePC;
     EndQuiesceEvent *quiesceEvent;
 
-    TheISA::Kernel::Statistics *kernelStats;
+    Kernel::Statistics *kernelStats;
 
   protected:
     Process *process;

src/kern/kernel_stats.hh

@@ -53,7 +53,7 @@ class Statistics : public Serializable
     virtual ~Statistics() {}
 
     const std::string name() const { return myname; }
-    void regStats(const std::string &name);
+    virtual void regStats(const std::string &name);
 
   public:
     void arm() { _arm++; }

src/sim/pseudo_inst.cc

@@ -53,7 +53,6 @@
 
 #include <gem5/asm/generic/m5ops.h>
 
-#include "arch/kernel_stats.hh"
 #include "arch/pseudo_inst.hh"
 #include "arch/utility.hh"
 #include "arch/vtophys.hh"
@@ -68,6 +67,7 @@
 #include "debug/Quiesce.hh"
 #include "debug/WorkItems.hh"
 #include "dev/net/dist_iface.hh"
+#include "kern/kernel_stats.hh"
 #include "params/BaseCPU.hh"
 #include "sim/full_system.hh"
 #include "sim/initparam_keys.hh"