ruby: reset and dump stats along with reset of the system

This patch adds support to ruby so that the statistics maintained by ruby
are reset/dumped when the statistics for the rest of the system are
reset/dumped. For resetting the statistics, ruby now provides the
resetStats() function that a sim object can provide. As a consequence, the
clearStats() function has been removed from RubySystem. For dumping stats,
Ruby now adds a callback event to the dumpStatsQueue. The exit callback that
ruby used to add earlier is being removed.

Created by: Hamid Reza Khaleghzadeh.
Improved by: Lluc Alvarez, Nilay Vaish
Committed by: Nilay Vaish

src/mem/ruby/profiler/Profiler.cc

@@ -438,6 +438,7 @@ void
 Profiler::clearStats()
 {
     m_ruby_start = g_system_ptr->getTime();
+    m_real_time_start_time = time(NULL);
 
     m_cycles_executed_at_start.resize(m_num_of_sequencers);
     for (int i = 0; i < m_num_of_sequencers; i++) {

src/mem/ruby/system/System.cc

@@ -32,7 +32,7 @@
 #include <cstdio>
 
 #include "base/intmath.hh"
-#include "base/output.hh"
+#include "base/statistics.hh"
 #include "debug/RubyCacheTrace.hh"
 #include "debug/RubySystem.hh"
 #include "mem/ruby/common/Address.hh"
@@ -80,8 +80,9 @@ RubySystem::RubySystem(const Params *p)
         m_mem_vec_ptr->resize(m_memory_size_bytes);
     }
 
-    // Print ruby configuration and stats at exit
-    registerExitCallback(new RubyExitCallback(p->stats_filename, this));
+    // Print ruby configuration and stats at exit and when asked for
+    Stats::registerDumpCallback(new RubyDumpStatsCallback(p->stats_filename,
+                                                          this));
 
     m_warmup_enabled = false;
     m_cooldown_enabled = false;
@@ -91,6 +92,7 @@ void
 RubySystem::init()
 {
     m_profiler_ptr->clearStats();
+    m_network_ptr->clearStats();
 }
 
 void
@@ -297,7 +299,7 @@ RubySystem::unserialize(Checkpoint *cp, const string &section)
     // that the profiler can correctly set its start time to the unserialized
     // value of curTick()
     //
-    clearStats();
+    resetStats();
     uint8_t *uncompressed_trace = NULL;
 
     if (m_mem_vec_ptr != NULL) {
@@ -391,7 +393,7 @@ RubySystem::RubyEvent::process()
 }
 
 void
-RubySystem::clearStats() const
+RubySystem::resetStats()
 {
     m_profiler_ptr->clearStats();
     m_network_ptr->clearStats();
@@ -625,8 +627,7 @@ RubySystemParams::create()
  * queue is executed.
  */
 void
-RubyExitCallback::process()
+RubyDumpStatsCallback::process()
 {
-    std::ostream *os = simout.create(stats_filename);
     ruby_system->printStats(*os);
 }

src/mem/ruby/system/System.hh

@@ -36,6 +36,7 @@
 #define __MEM_RUBY_SYSTEM_SYSTEM_HH__
 
 #include "base/callback.hh"
+#include "base/output.hh"
 #include "mem/packet.hh"
 #include "mem/ruby/common/Global.hh"
 #include "mem/ruby/recorder/CacheRecorder.hh"
@@ -103,7 +104,7 @@ class RubySystem : public ClockedObject
     }
 
     void printStats(std::ostream& out);
-    void clearStats() const;
+    void resetStats();
 
     uint64 getInstructionCount(int thread) { return 1; }
 
@@ -172,18 +173,19 @@ operator<<(std::ostream& out, const RubySystem& obj)
     return out;
 }
 
-class RubyExitCallback : public Callback
+class RubyDumpStatsCallback : public Callback
 {
   private:
-    std::string stats_filename;
+    std::ostream *os;
     RubySystem *ruby_system;
 
   public:
-    virtual ~RubyExitCallback() {}
+    virtual ~RubyDumpStatsCallback() {}
 
-    RubyExitCallback(const std::string& _stats_filename, RubySystem *system)
+    RubyDumpStatsCallback(const std::string& _stats_filename,
+                          RubySystem *system)
     {
-        stats_filename = _stats_filename;
+        os = simout.create(_stats_filename);
         ruby_system = system;
     }