From 5cd9dd29bdb56fe496d78fcef0dfb0d6230ddc77 Mon Sep 17 00:00:00 2001
From: Nilay Vaish <nilay@cs.wisc.edu>
Date: Sat, 1 Mar 2014 23:59:58 -0600
Subject: [PATCH] ruby: message buffer: changes related to tracking push/pop
 times The last pop operation is now tracked as a Tick instead of in Cycles.
 This helps in avoiding use of the receiver's clock during the enqueue
 operation.

---
 src/mem/ruby/buffers/MessageBuffer.cc | 10 +++++-----
 src/mem/ruby/buffers/MessageBuffer.hh |  6 +++---
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/mem/ruby/buffers/MessageBuffer.cc b/src/mem/ruby/buffers/MessageBuffer.cc
index 0486f627e..19ad9ee7d 100644
--- a/src/mem/ruby/buffers/MessageBuffer.cc
+++ b/src/mem/ruby/buffers/MessageBuffer.cc
@@ -89,11 +89,11 @@ MessageBuffer::areNSlotsAvailable(unsigned int n)
     // size immediately
     unsigned int current_size = 0;
 
-    if (m_time_last_time_pop < m_receiver->curCycle()) {
+    if (m_time_last_time_pop < m_sender->clockEdge()) {
         // no pops this cycle - heap size is correct
         current_size = m_prio_heap.size();
     } else {
-        if (m_time_last_time_enqueue < m_receiver->curCycle()) {
+        if (m_time_last_time_enqueue < m_sender->curCycle()) {
             // no enqueues this cycle - m_size_at_cycle_start is correct
             current_size = m_size_at_cycle_start;
         } else {
@@ -242,9 +242,9 @@ MessageBuffer::dequeue()
 
     // record previous size and time so the current buffer size isn't
     // adjusted until next cycle
-    if (m_time_last_time_pop < m_receiver->curCycle()) {
+    if (m_time_last_time_pop < m_receiver->clockEdge()) {
         m_size_at_cycle_start = m_prio_heap.size();
-        m_time_last_time_pop = m_receiver->curCycle();
+        m_time_last_time_pop = m_receiver->clockEdge();
     }
 
     pop_heap(m_prio_heap.begin(), m_prio_heap.end(),
@@ -259,7 +259,7 @@ MessageBuffer::clear()
 
     m_msg_counter = 0;
     m_time_last_time_enqueue = Cycles(0);
-    m_time_last_time_pop = Cycles(0);
+    m_time_last_time_pop = 0;
     m_size_at_cycle_start = 0;
     m_msgs_this_cycle = 0;
 }
diff --git a/src/mem/ruby/buffers/MessageBuffer.hh b/src/mem/ruby/buffers/MessageBuffer.hh
index 444a7fc30..6019f3d6c 100644
--- a/src/mem/ruby/buffers/MessageBuffer.hh
+++ b/src/mem/ruby/buffers/MessageBuffer.hh
@@ -186,7 +186,9 @@ class MessageBuffer
     // variables used so enqueues appear to happen imediately, while
     // pop happen the next cycle
     Cycles m_time_last_time_enqueue;
-    Cycles m_time_last_time_pop;
+    Tick m_time_last_time_pop;
+    Tick m_last_arrival_time;
+
     unsigned int m_size_at_cycle_start;
     unsigned int m_msgs_this_cycle;
 
@@ -198,8 +200,6 @@ class MessageBuffer
     bool m_ordering_set;
     bool m_randomization;
 
-    Tick m_last_arrival_time;
-
     int m_input_link_id;
     int m_vnet_id;
 };