sim: have a curTick per eventq

This patch adds a _curTick variable to an eventq. This variable is updated
whenever an event is serviced in function serviceOne(), or all events upto
a particular time are processed in function serviceEvents(). This change
helps when there are eventqs that do not make use of curTick for scheduling
events.

12 files changed, 123 insertions, 77 deletions

diff --git a/src/sim/clocked_object.hh b/src/sim/clocked_object.hh
index 9a4c1034a..d9630139a 100644
--- a/src/sim/clocked_object.hh
+++ b/src/sim/clocked_object.hh
@@ -47,6 +47,7 @@
 
 #include "base/intmath.hh"
 #include "params/ClockedObject.hh"
+#include "sim/core.hh"
 #include "sim/sim_object.hh"
 
 /**
diff --git a/src/sim/core.cc b/src/sim/core.cc
index ab75e1d9a..aa618bdb3 100644
--- a/src/sim/core.cc
+++ b/src/sim/core.cc
@@ -35,11 +35,10 @@
 #include "base/callback.hh"
 #include "base/output.hh"
 #include "sim/core.hh"
+#include "sim/eventq.hh"
 
 using namespace std;
 
-Tick _curTick = 0;
-
 namespace SimClock {
 /// The simulated frequency of curTick(). (In ticks per second)
 Tick Frequency;
diff --git a/src/sim/core.hh b/src/sim/core.hh
index 4f842ab48..b5a082bcb 100644
--- a/src/sim/core.hh
+++ b/src/sim/core.hh
@@ -39,12 +39,10 @@
 #include <string>
 
 #include "base/types.hh"
+#include "sim/eventq.hh"
 
 /// The universal simulation clock.
-extern Tick _curTick;
-
-inline Tick curTick() { return _curTick; }
-inline void curTick(Tick newVal) { _curTick = newVal; }
+inline Tick curTick() { return mainEventQueue.getCurTick(); }
 
 const Tick retryTime = 1000;
 
diff --git a/src/sim/debug.cc b/src/sim/debug.cc
index fadd89ae1..51b92740e 100644
--- a/src/sim/debug.cc
+++ b/src/sim/debug.cc
@@ -36,7 +36,7 @@
 
 #include "base/debug.hh"
 #include "sim/debug.hh"
-#include "sim/eventq.hh"
+#include "sim/eventq_impl.hh"
 #include "sim/sim_events.hh"
 #include "sim/sim_exit.hh"
 
diff --git a/src/sim/eventq.cc b/src/sim/eventq.cc
index b32b330e7..d81937a86 100644
--- a/src/sim/eventq.cc
+++ b/src/sim/eventq.cc
@@ -42,7 +42,7 @@
 #include "cpu/smt.hh"
 #include "debug/Config.hh"
 #include "sim/core.hh"
-#include "sim/eventq.hh"
+#include "sim/eventq_impl.hh"
 
 using namespace std;
 
@@ -201,6 +201,9 @@ EventQueue::serviceOne()
 
     // handle action
     if (!event->squashed()) {
+        // forward current cycle to the time when this event occurs.
+        setCurTick(event->when());
+
         event->process();
         if (event->isExitEvent()) {
             assert(!event->flags.isSet(Event::AutoDelete) ||
@@ -429,5 +432,5 @@ Event::dump() const
 }
 
 EventQueue::EventQueue(const string &n)
-    : objName(n), head(NULL)
+    : objName(n), head(NULL), _curTick(0)
 {}
diff --git a/src/sim/eventq.hh b/src/sim/eventq.hh
index 5362dcf34..5d5764a6a 100644
--- a/src/sim/eventq.hh
+++ b/src/sim/eventq.hh
@@ -44,7 +44,6 @@
 
 #include "base/flags.hh"
 #include "base/misc.hh"
-#include "base/trace.hh"
 #include "base/types.hh"
 #include "debug/Event.hh"
 #include "sim/serialize.hh"
@@ -361,6 +360,7 @@ class EventQueue : public Serializable
   private:
     std::string objName;
     Event *head;
+    Tick _curTick;
 
     void insert(Event *event);
     void remove(Event *event);
@@ -379,6 +379,9 @@ class EventQueue : public Serializable
     void reschedule(Event *event, Tick when, bool always = false);
 
     Tick nextTick() const { return head->when(); }
+    void setCurTick(Tick newVal) { _curTick = newVal; }
+    Tick getCurTick() { return _curTick; }
+
     Event *serviceOne();
 
     // process all events up to the given timestamp.  we inline a
@@ -398,6 +401,8 @@ class EventQueue : public Serializable
             //assert(head->when() >= when && "event scheduled in the past");
             serviceOne();
         }
+
+        setCurTick(when);
     }
 
     // return true if no events are queued
@@ -476,67 +481,9 @@ class EventManager
     {
         eventq->reschedule(event, when, always);
     }
-};
-
-inline void
-EventQueue::schedule(Event *event, Tick when)
-{
-    assert(when >= curTick());
-    assert(!event->scheduled());
-    assert(event->initialized());
-
-    event->setWhen(when, this);
-    insert(event);
-    event->flags.set(Event::Scheduled);
-    if (this == &mainEventQueue)
-        event->flags.set(Event::IsMainQueue);
-    else
-        event->flags.clear(Event::IsMainQueue);
-
-    if (DTRACE(Event))
-        event->trace("scheduled");
-}
-
-inline void
-EventQueue::deschedule(Event *event)
-{
-    assert(event->scheduled());
-    assert(event->initialized());
 
-    remove(event);
-
-    event->flags.clear(Event::Squashed);
-    event->flags.clear(Event::Scheduled);
-
-    if (DTRACE(Event))
-        event->trace("descheduled");
-
-    if (event->flags.isSet(Event::AutoDelete))
-        delete event;
-}
-
-inline void
-EventQueue::reschedule(Event *event, Tick when, bool always)
-{
-    assert(when >= curTick());
-    assert(always || event->scheduled());
-    assert(event->initialized());
-
-    if (event->scheduled())
-        remove(event);
-            
-    event->setWhen(when, this);
-    insert(event);
-    event->flags.clear(Event::Squashed);
-    event->flags.set(Event::Scheduled);
-    if (this == &mainEventQueue)
-        event->flags.set(Event::IsMainQueue);
-    else
-        event->flags.clear(Event::IsMainQueue);
-
-    if (DTRACE(Event))
-        event->trace("rescheduled");
-}
+    void setCurTick(Tick newVal) { eventq->setCurTick(newVal); }
+};
 
 template <class T, void (T::* F)()>
 void
diff --git a/src/sim/eventq_impl.hh b/src/sim/eventq_impl.hh
new file mode 100644
index 000000000..c53a4da77
--- /dev/null
+++ b/src/sim/eventq_impl.hh
@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2012 The Regents of The University of Michigan
+ * Copyright (c) 2012 Mark D. Hill and David A. Wood
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Steve Reinhardt
+ *          Nathan Binkert
+ *          Nilay Vaish
+ */
+
+#ifndef __SIM_EVENTQ_IMPL_HH__
+#define __SIM_EVENTQ_IMPL_HH__
+
+#include "base/trace.hh"
+#include "sim/eventq.hh"
+
+inline void
+EventQueue::schedule(Event *event, Tick when)
+{
+    assert(when >= getCurTick());
+    assert(!event->scheduled());
+    assert(event->initialized());
+
+    event->setWhen(when, this);
+    insert(event);
+    event->flags.set(Event::Scheduled);
+    if (this == &mainEventQueue)
+        event->flags.set(Event::IsMainQueue);
+    else
+        event->flags.clear(Event::IsMainQueue);
+
+    if (DTRACE(Event))
+        event->trace("scheduled");
+}
+
+inline void
+EventQueue::deschedule(Event *event)
+{
+    assert(event->scheduled());
+    assert(event->initialized());
+
+    remove(event);
+
+    event->flags.clear(Event::Squashed);
+    event->flags.clear(Event::Scheduled);
+
+    if (DTRACE(Event))
+        event->trace("descheduled");
+
+    if (event->flags.isSet(Event::AutoDelete))
+        delete event;
+}
+
+inline void
+EventQueue::reschedule(Event *event, Tick when, bool always)
+{
+    assert(when >= getCurTick());
+    assert(always || event->scheduled());
+    assert(event->initialized());
+
+    if (event->scheduled())
+        remove(event);
+
+    event->setWhen(when, this);
+    insert(event);
+    event->flags.clear(Event::Squashed);
+    event->flags.set(Event::Scheduled);
+    if (this == &mainEventQueue)
+        event->flags.set(Event::IsMainQueue);
+    else
+        event->flags.clear(Event::IsMainQueue);
+
+    if (DTRACE(Event))
+        event->trace("rescheduled");
+}
+
+#endif // __SIM_EVENTQ_IMPL_HH__
diff --git a/src/sim/root.cc b/src/sim/root.cc
index b8fadf190..f77159486 100644
--- a/src/sim/root.cc
+++ b/src/sim/root.cc
@@ -32,6 +32,7 @@
  */
 
 #include "base/misc.hh"
+#include "base/trace.hh"
 #include "config/the_isa.hh"
 #include "debug/TimeSync.hh"
 #include "sim/full_system.hh"
diff --git a/src/sim/serialize.cc b/src/sim/serialize.cc
index 54b7926d6..9ef92d449 100644
--- a/src/sim/serialize.cc
+++ b/src/sim/serialize.cc
@@ -465,7 +465,7 @@ Globals::unserialize(Checkpoint *cp, const std::string &section)
 {
     Tick tick;
     paramIn(cp, section, "curTick", tick);
-    curTick(tick);
+    mainEventQueue.setCurTick(tick);
 
     mainEventQueue.unserialize(cp, "MainEventQueue");
 }
diff --git a/src/sim/sim_events.cc b/src/sim/sim_events.cc
index 2354e89f7..0ae7e573e 100644
--- a/src/sim/sim_events.cc
+++ b/src/sim/sim_events.cc
@@ -32,7 +32,7 @@
 
 #include "base/callback.hh"
 #include "base/hostinfo.hh"
-#include "sim/eventq.hh"
+#include "sim/eventq_impl.hh"
 #include "sim/sim_events.hh"
 #include "sim/sim_exit.hh"
 #include "sim/stats.hh"
diff --git a/src/sim/sim_object.hh b/src/sim/sim_object.hh
index f04289e2f..6424f631b 100644
--- a/src/sim/sim_object.hh
+++ b/src/sim/sim_object.hh
@@ -46,7 +46,7 @@
 #include "enums/MemoryMode.hh"
 #include "params/SimObject.hh"
 #include "sim/drain.hh"
-#include "sim/eventq.hh"
+#include "sim/eventq_impl.hh"
 #include "sim/serialize.hh"
 
 class BaseCPU;
diff --git a/src/sim/simulate.cc b/src/sim/simulate.cc
index 238e68787..6962fab9f 100644
--- a/src/sim/simulate.cc
+++ b/src/sim/simulate.cc
@@ -33,7 +33,7 @@
 #include "base/pollevent.hh"
 #include "base/types.hh"
 #include "sim/async.hh"
-#include "sim/eventq.hh"
+#include "sim/eventq_impl.hh"
 #include "sim/sim_events.hh"
 #include "sim/sim_exit.hh"
 #include "sim/simulate.hh"
@@ -65,9 +65,6 @@ simulate(Tick num_cycles)
         assert(curTick() <= mainEventQueue.nextTick() &&
                "event scheduled in the past");
 
-        // forward current cycle to the time of the first event on the
-        // queue
-        curTick(mainEventQueue.nextTick());
         Event *exit_event = mainEventQueue.serviceOne();
         if (exit_event != NULL) {
             // hit some kind of exit event; return to Python