Fix so that O3CPU doesnt segfault on exit.

Major thing was to not execute commit if there are no active threads in CPU.

src/cpu/o3/alpha/thread_context.hh:
    call deallocate instead of deallocateContext
src/cpu/o3/commit_impl.hh:
    dont run commit stage if there are no instructions
src/cpu/o3/cpu.cc:
    add deallocate event, deactivateThread function, and edit deallocateContext.
src/cpu/o3/cpu.hh:
    add deallocate event and add optional delay to deallocateContext
src/cpu/o3/thread_context.hh:
    optional delay for deallocate
src/cpu/o3/thread_context_impl.hh:
    edit DPRINTFs to say Thread Context instead of Alpha TC
src/cpu/thread_context.hh:
    optional delay
src/sim/syscall_emul.hh:
    name stuff

--HG--
extra : convert_revision : f4033e1f66b3043d30ad98dcc70d8b193dea70b6

6 files changed, 216 insertions, 119 deletions

diff --git a/src/cpu/o3/alpha/thread_context.hh b/src/cpu/o3/alpha/thread_context.hh
index 78b0ee788..ad52b0d2e 100644
--- a/src/cpu/o3/alpha/thread_context.hh
+++ b/src/cpu/o3/alpha/thread_context.hh
@@ -70,18 +70,19 @@ class AlphaTC : public O3ThreadContext<Impl>
     { panic("Not supported on Alpha!"); }
 
 
-    // This function exits the thread context in the CPU and returns
-    // 1 if the CPU has no more active threads (meaning it's OK to exit);
-    // Used in syscall-emulation mode when a thread executes the 'exit'
-    // syscall.
+    /** This function exits the thread context in the CPU and returns
+     * 1 if the CPU has no more active threads (meaning it's OK to exit);
+     * Used in syscall-emulation mode when a thread executes the 'exit'
+     * syscall.
+     */
     virtual int exit()
     {
-        this->cpu->deallocateContext(this->thread->readTid());
+        this->deallocate();
 
         // If there are still threads executing in the system
         if (this->cpu->numActiveThreads())
-            return 0;
+            return 0; // don't exit simulation
         else
-            return 1;
+            return 1; // exit simulation
     }
 };
diff --git a/src/cpu/o3/commit_impl.hh b/src/cpu/o3/commit_impl.hh
index 06b8e8a95..53d247e97 100644
--- a/src/cpu/o3/commit_impl.hh
+++ b/src/cpu/o3/commit_impl.hh
@@ -562,6 +562,9 @@ DefaultCommit<Impl>::tick()
         return;
     }
 
+    if ((*activeThreads).size() <= 0)
+        return;
+
     list<unsigned>::iterator threads = (*activeThreads).begin();
 
     // Check if any of the threads are done squashing.  Change the
diff --git a/src/cpu/o3/cpu.cc b/src/cpu/o3/cpu.cc
index c88146fa6..0a564169a 100644
--- a/src/cpu/o3/cpu.cc
+++ b/src/cpu/o3/cpu.cc
@@ -115,6 +115,36 @@ FullO3CPU<Impl>::ActivateThreadEvent::description()
 }
 
 template <class Impl>
+FullO3CPU<Impl>::DeallocateContextEvent::DeallocateContextEvent()
+    : Event(&mainEventQueue, CPU_Tick_Pri)
+{
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::DeallocateContextEvent::init(int thread_num,
+                                           FullO3CPU<Impl> *thread_cpu)
+{
+    tid = thread_num;
+    cpu = thread_cpu;
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::DeallocateContextEvent::process()
+{
+    cpu->deactivateThread(tid);
+    cpu->removeThread(tid);
+}
+
+template <class Impl>
+const char *
+FullO3CPU<Impl>::DeallocateContextEvent::description()
+{
+    return "FullO3CPU \"Deallocate Context\" event";
+}
+
+template <class Impl>
 FullO3CPU<Impl>::FullO3CPU(Params *params)
     : BaseO3CPU(params),
       tickEvent(this),
@@ -461,6 +491,118 @@ FullO3CPU<Impl>::init()
 
 template <class Impl>
 void
+FullO3CPU<Impl>::activateThread(unsigned tid)
+{
+    list<unsigned>::iterator isActive = find(
+        activeThreads.begin(), activeThreads.end(), tid);
+
+    if (isActive == activeThreads.end()) {
+        DPRINTF(O3CPU, "[tid:%i]: Adding to active threads list\n",
+                tid);
+
+        activeThreads.push_back(tid);
+    }
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::deactivateThread(unsigned tid)
+{
+    //Remove From Active List, if Active
+    list<unsigned>::iterator thread_it =
+        find(activeThreads.begin(), activeThreads.end(), tid);
+
+    if (thread_it != activeThreads.end()) {
+        DPRINTF(O3CPU,"[tid:%i]: Removing from active threads list\n",
+                tid);
+        activeThreads.erase(thread_it);
+    }
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::activateContext(int tid, int delay)
+{
+    // Needs to set each stage to running as well.
+    if (delay){
+        DPRINTF(O3CPU, "[tid:%i]: Scheduling thread context to activate "
+                "on cycle %d\n", tid, curTick + cycles(delay));
+        scheduleActivateThreadEvent(tid, delay);
+    } else {
+        activateThread(tid);
+    }
+
+    if(lastActivatedCycle < curTick) {
+        scheduleTickEvent(delay);
+
+        // Be sure to signal that there's some activity so the CPU doesn't
+        // deschedule itself.
+        activityRec.activity();
+        fetch.wakeFromQuiesce();
+
+        lastActivatedCycle = curTick;
+
+        _status = Running;
+    }
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::deallocateContext(int tid, int delay)
+{
+    // Schedule removal of thread data from CPU
+    if (delay){
+        DPRINTF(O3CPU, "[tid:%i]: Scheduling thread context to deallocate "
+                "on cycle %d\n", tid, curTick + cycles(delay));
+        scheduleDeallocateContextEvent(tid, delay);
+    } else {
+        deactivateThread(tid);
+        removeThread(tid);
+    }
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::suspendContext(int tid)
+{
+    DPRINTF(O3CPU,"[tid: %i]: Suspending Thread Context.\n", tid);
+    unscheduleTickEvent();
+    _status = Idle;
+/*
+    //Remove From Active List, if Active
+    list<unsigned>::iterator isActive = find(
+        activeThreads.begin(), activeThreads.end(), tid);
+
+    if (isActive != activeThreads.end()) {
+        DPRINTF(O3CPU,"[tid:%i]: Removing from active threads list\n",
+                tid);
+        activeThreads.erase(isActive);
+    }
+*/
+}
+
+template <class Impl>
+void
+FullO3CPU<Impl>::haltContext(int tid)
+{
+    DPRINTF(O3CPU,"[tid:%i]: Halting Thread Context", tid);
+/*
+    //Remove From Active List, if Active
+    list<unsigned>::iterator isActive = find(
+        activeThreads.begin(), activeThreads.end(), tid);
+
+    if (isActive != activeThreads.end()) {
+        DPRINTF(O3CPU,"[tid:%i]: Removing from active threads list\n",
+                tid);
+        activeThreads.erase(isActive);
+
+        removeThread(tid);
+    }
+*/
+}
+
+template <class Impl>
+void
 FullO3CPU<Impl>::insertThread(unsigned tid)
 {
     DPRINTF(O3CPU,"[tid:%i] Initializing thread into CPU");
@@ -511,7 +653,7 @@ template <class Impl>
 void
 FullO3CPU<Impl>::removeThread(unsigned tid)
 {
-    DPRINTF(O3CPU,"[tid:%i] Removing thread from CPU.");
+    DPRINTF(O3CPU,"[tid:%i] Removing thread context from CPU.");
 
     // Copy Thread Data From RegFile
     // If thread is suspended, it might be re-allocated
@@ -537,6 +679,8 @@ FullO3CPU<Impl>::removeThread(unsigned tid)
     fetch.squash(0,tid);
     decode.squash(tid);
     rename.squash(tid);
+    iew.squash(tid);
+    commit.rob->squash(commit.rob->readHeadInst(tid)->seqNum, tid);
 
     assert(iew.ldstQueue.getCount(tid) == 0);
 
@@ -600,6 +744,7 @@ FullO3CPU<Impl>::activateWhenReady(int tid)
         //blocks fetch
         contextSwitch = true;
 
+        //@todo: dont always add to waitlist
         //do waitlist
         cpuWaitList.push_back(tid);
     }
@@ -607,108 +752,6 @@ FullO3CPU<Impl>::activateWhenReady(int tid)
 
 template <class Impl>
 void
-FullO3CPU<Impl>::activateThread(unsigned int tid)
-{
-    list<unsigned>::iterator isActive = find(
-        activeThreads.begin(), activeThreads.end(), tid);
-
-    if (isActive == activeThreads.end()) {
-        DPRINTF(O3CPU, "[tid:%i]: Adding to active threads list\n",
-                tid);
-
-        activeThreads.push_back(tid);
-    }
-}
-
-
-template <class Impl>
-void
-FullO3CPU<Impl>::activateContext(int tid, int delay)
-{
-    // Needs to set each stage to running as well.
-    if (delay){
-        DPRINTF(O3CPU, "[tid:%i]: Scheduling thread context to activate "
-                "on cycle %d\n", tid, curTick + cycles(delay));
-        scheduleActivateThreadEvent(tid, delay);
-    } else {
-        activateThread(tid);
-    }
-
-    if(lastActivatedCycle < curTick) {
-        scheduleTickEvent(delay);
-
-        // Be sure to signal that there's some activity so the CPU doesn't
-        // deschedule itself.
-        activityRec.activity();
-        fetch.wakeFromQuiesce();
-
-        lastActivatedCycle = curTick;
-
-        _status = Running;
-    }
-}
-
-template <class Impl>
-void
-FullO3CPU<Impl>::suspendContext(int tid)
-{
-    DPRINTF(O3CPU,"[tid: %i]: Suspending Thread Context.\n", tid);
-    unscheduleTickEvent();
-    _status = Idle;
-/*
-    //Remove From Active List, if Active
-    list<unsigned>::iterator isActive = find(
-        activeThreads.begin(), activeThreads.end(), tid);
-
-    if (isActive != activeThreads.end()) {
-        DPRINTF(O3CPU,"[tid:%i]: Removing from active threads list\n",
-                tid);
-        activeThreads.erase(isActive);
-    }
-*/
-}
-
-template <class Impl>
-void
-FullO3CPU<Impl>::deallocateContext(int tid)
-{
-    DPRINTF(O3CPU,"[tid:%i]: Deallocating Thread Context", tid);
-
-    //Remove From Active List, if Active
-    list<unsigned>::iterator thread_it =
-        find(activeThreads.begin(), activeThreads.end(), tid);
-
-    if (thread_it != activeThreads.end()) {
-        DPRINTF(O3CPU,"[tid:%i]: Removing from active threads list\n",
-                tid);
-        activeThreads.erase(thread_it);
-
-        removeThread(tid);
-    }
-}
-
-template <class Impl>
-void
-FullO3CPU<Impl>::haltContext(int tid)
-{
-    DPRINTF(O3CPU,"[tid:%i]: Halting Thread Context", tid);
-/*
-    //Remove From Active List, if Active
-    list<unsigned>::iterator isActive = find(
-        activeThreads.begin(), activeThreads.end(), tid);
-
-    if (isActive != activeThreads.end()) {
-        DPRINTF(O3CPU,"[tid:%i]: Removing from active threads list\n",
-                tid);
-        activeThreads.erase(isActive);
-
-        removeThread(tid);
-    }
-*/
-}
-
-template <class Impl>
-void
 FullO3CPU<Impl>::switchOut()
 {
     switchCount = 0;
diff --git a/src/cpu/o3/cpu.hh b/src/cpu/o3/cpu.hh
index bd0451601..476b5ffb3 100644
--- a/src/cpu/o3/cpu.hh
+++ b/src/cpu/o3/cpu.hh
@@ -197,6 +197,49 @@ class FullO3CPU : public BaseO3CPU
     /** The tick event used for scheduling CPU ticks. */
     ActivateThreadEvent activateThreadEvent[Impl::MaxThreads];
 
+    class DeallocateContextEvent : public Event
+    {
+      private:
+        /** Number of Thread to Activate */
+        int tid;
+
+        /** Pointer to the CPU. */
+        FullO3CPU<Impl> *cpu;
+
+      public:
+        /** Constructs the event. */
+        DeallocateContextEvent();
+
+        /** Initialize Event */
+        void init(int thread_num, FullO3CPU<Impl> *thread_cpu);
+
+        /** Processes the event, calling activateThread() on the CPU. */
+        void process();
+
+        /** Returns the description of the event. */
+        const char *description();
+    };
+
+    /** Schedule cpu to deallocate thread context.*/
+    void scheduleDeallocateContextEvent(int tid, int delay)
+    {
+        // Schedule thread to activate, regardless of its current state.
+        if (deallocateContextEvent[tid].squashed())
+            deallocateContextEvent[tid].reschedule(curTick + cycles(delay));
+        else if (!deallocateContextEvent[tid].scheduled())
+            deallocateContextEvent[tid].schedule(curTick + cycles(delay));
+    }
+
+    /** Unschedule thread deallocation in CPU */
+    void unscheduleDeallocateContextEvent(int tid)
+    {
+        if (deallocateContextEvent[tid].scheduled())
+            deallocateContextEvent[tid].squash();
+    }
+
+    /** The tick event used for scheduling CPU ticks. */
+    DeallocateContextEvent deallocateContextEvent[Impl::MaxThreads];
+
   public:
     /** Constructs a CPU with the given parameters. */
     FullO3CPU(Params *params);
@@ -219,7 +262,10 @@ class FullO3CPU : public BaseO3CPU
     { return activeThreads.size(); }
 
     /** Add Thread to Active Threads List */
-    void activateThread(unsigned int tid);
+    void activateThread(unsigned tid);
+
+    /** Remove Thread from Active Threads List */
+    void deactivateThread(unsigned tid);
 
     /** Setup CPU to insert a thread's context */
     void insertThread(unsigned tid);
@@ -247,7 +293,7 @@ class FullO3CPU : public BaseO3CPU
     /** Remove Thread from Active Threads List &&
      *  Remove Thread Context from CPU.
      */
-    void deallocateContext(int tid);
+    void deallocateContext(int tid, int delay = 1);
 
     /** Remove Thread from Active Threads List &&
      *  Remove Thread Context from CPU.
diff --git a/src/cpu/o3/thread_context.hh b/src/cpu/o3/thread_context.hh
index d097ee63e..df8d1a6d8 100755
--- a/src/cpu/o3/thread_context.hh
+++ b/src/cpu/o3/thread_context.hh
@@ -112,7 +112,7 @@ class O3ThreadContext : public ThreadContext
     virtual void suspend();
 
     /** Set the status to Unallocated. */
-    virtual void deallocate();
+    virtual void deallocate(int delay = 0);
 
     /** Set the status to Halted. */
     virtual void halt();
diff --git a/src/cpu/o3/thread_context_impl.hh b/src/cpu/o3/thread_context_impl.hh
index cfb71f623..bf8cbf850 100755
--- a/src/cpu/o3/thread_context_impl.hh
+++ b/src/cpu/o3/thread_context_impl.hh
@@ -115,7 +115,8 @@ template <class Impl>
 void
 O3ThreadContext<Impl>::activate(int delay)
 {
-    DPRINTF(O3CPU, "Calling activate on AlphaTC\n");
+    DPRINTF(O3CPU, "Calling activate on Thread Context %d\n",
+            getThreadNum());
 
     if (thread->status() == ThreadContext::Active)
         return;
@@ -139,7 +140,8 @@ template <class Impl>
 void
 O3ThreadContext<Impl>::suspend()
 {
-    DPRINTF(O3CPU, "Calling suspend on AlphaTC\n");
+    DPRINTF(O3CPU, "Calling suspend on Thread Context %d\n",
+            getThreadNum());
 
     if (thread->status() == ThreadContext::Suspended)
         return;
@@ -163,22 +165,24 @@ O3ThreadContext<Impl>::suspend()
 
 template <class Impl>
 void
-O3ThreadContext<Impl>::deallocate()
+O3ThreadContext<Impl>::deallocate(int delay)
 {
-    DPRINTF(O3CPU, "Calling deallocate on AlphaTC\n");
+    DPRINTF(O3CPU, "Calling deallocate on Thread Context %d\n",
+            getThreadNum());
 
     if (thread->status() == ThreadContext::Unallocated)
         return;
 
     thread->setStatus(ThreadContext::Unallocated);
-    cpu->deallocateContext(thread->readTid());
+    cpu->deallocateContext(thread->readTid(), delay);
 }
 
 template <class Impl>
 void
 O3ThreadContext<Impl>::halt()
 {
-    DPRINTF(O3CPU, "Calling halt on AlphaTC\n");
+    DPRINTF(O3CPU, "Calling halt on Thread Context %d\n",
+            getThreadNum());
 
     if (thread->status() == ThreadContext::Halted)
         return;