1 files changed, 300 insertions, 0 deletions

diff --git a/src/mem/ruby/system/StoreBuffer.cc b/src/mem/ruby/system/StoreBuffer.cc
new file mode 100644
index 000000000..c6880bdd1
--- /dev/null
+++ b/src/mem/ruby/system/StoreBuffer.cc
@@ -0,0 +1,300 @@
+
+/*
+ * Copyright (c) 1999-2008 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.
+ */
+
+/*
+ * $Id$
+ *
+ */
+
+#include "Global.hh"
+#include "RubyConfig.hh"
+#include "StoreBuffer.hh"
+#include "AbstractChip.hh"
+#include "System.hh"
+#include "Driver.hh"
+#include "Vector.hh"
+#include "EventQueue.hh"
+#include "AddressProfiler.hh"
+#include "Sequencer.hh"
+#include "SubBlock.hh"
+#include "Profiler.hh"
+
+// *** Begin Helper class ***
+struct StoreBufferEntry {
+  StoreBufferEntry() {} // So we can allocate a vector of StoreBufferEntries
+  StoreBufferEntry(const SubBlock& block, CacheRequestType type, const Address& pc, AccessModeType access_mode, int size, int thread) : m_subblock(block) {
+    m_type = type;
+    m_pc = pc;
+    m_access_mode = access_mode;
+    m_size = size;
+    m_thread = thread;
+    m_time = g_eventQueue_ptr->getTime();
+  }
+
+  void print(ostream& out) const
+  {
+    out << "[StoreBufferEntry: "
+        << "SubBlock: " << m_subblock
+        << ", Type: " << m_type
+        << ", PC: " << m_pc
+        << ", AccessMode: " << m_access_mode
+        << ", Size: " << m_size
+        << ", Thread: " << m_thread
+        << ", Time: " << m_time
+        << "]";
+  }
+
+  SubBlock m_subblock;
+  CacheRequestType m_type;
+  Address m_pc;
+  AccessModeType m_access_mode;
+  int m_size;
+  int m_thread;
+  Time m_time;
+};
+
+extern inline
+ostream& operator<<(ostream& out, const StoreBufferEntry& obj)
+{
+  obj.print(out);
+  out << flush;
+  return out;
+}
+
+// *** End Helper class ***
+
+const int MAX_ENTRIES = 128;
+
+static void inc_index(int& index)
+{
+  index++;
+  if (index >= MAX_ENTRIES) {
+    index = 0;
+  }
+}
+
+StoreBuffer::StoreBuffer(AbstractChip* chip_ptr, int version) :
+  m_store_cache()
+{
+  m_chip_ptr = chip_ptr;
+  m_version = version;
+  m_queue_ptr = new Vector<StoreBufferEntry>(MAX_ENTRIES);
+  m_queue_ptr->setSize(MAX_ENTRIES);
+  m_pending = false;
+  m_seen_atomic = false;
+  m_head = 0;
+  m_tail = 0;
+  m_size = 0;
+  m_deadlock_check_scheduled = false;
+}
+
+StoreBuffer::~StoreBuffer()
+{
+  delete m_queue_ptr;
+}
+
+// Used only to check for deadlock
+void StoreBuffer::wakeup()
+{
+  // Check for deadlock of any of the requests
+  Time current_time = g_eventQueue_ptr->getTime();
+
+  int queue_pointer = m_head;
+  for (int i=0; i<m_size; i++) {
+    if (current_time - (getEntry(queue_pointer).m_time) >= g_DEADLOCK_THRESHOLD) {
+      WARN_EXPR(getEntry(queue_pointer));
+      WARN_EXPR(m_chip_ptr->getID());
+      WARN_EXPR(current_time);
+      ERROR_MSG("Possible Deadlock detected");
+    }
+    inc_index(queue_pointer);
+  }
+
+  if (m_size > 0) { // If there are still outstanding requests, keep checking
+    g_eventQueue_ptr->scheduleEvent(this, g_DEADLOCK_THRESHOLD);
+  } else {
+    m_deadlock_check_scheduled = false;
+  }
+}
+
+void StoreBuffer::printConfig(ostream& out)
+{
+  out << "Store buffer entries: " << MAX_ENTRIES << " (Only valid if TSO is enabled)" << endl;
+}
+
+// Handle an incoming store request, this method is responsible for
+// calling hitCallback as needed
+void StoreBuffer::insertStore(const CacheMsg& request)
+{
+  Address addr = request.getAddress();
+  CacheRequestType type = request.getType();
+  Address pc = request.getProgramCounter();
+  AccessModeType access_mode = request.getAccessMode();
+  int size = request.getSize();
+  int threadID = request.getThreadID();
+
+  DEBUG_MSG(STOREBUFFER_COMP, MedPrio, "insertStore");
+  DEBUG_EXPR(STOREBUFFER_COMP, MedPrio, g_eventQueue_ptr->getTime());
+  assert((type == CacheRequestType_ST) || (type == CacheRequestType_ATOMIC));
+  assert(isReady());
+
+  // See if we should schedule a deadlock check
+  if (m_deadlock_check_scheduled == false) {
+    g_eventQueue_ptr->scheduleEvent(this, g_DEADLOCK_THRESHOLD);
+    m_deadlock_check_scheduled = true;
+  }
+
+  // Perform the hit-callback for the store
+  SubBlock subblock(addr, size);
+  if(type == CacheRequestType_ST) {
+    g_system_ptr->getDriver()->hitCallback(m_chip_ptr->getID(), subblock, type, threadID);
+    assert(subblock.getSize() != 0);
+  } else {
+    // wait to perform the hitCallback until later for Atomics
+  }
+
+  // Perform possible pre-fetch
+  if(!isEmpty()) {
+    CacheMsg new_request = request;
+    new_request.getPrefetch() = PrefetchBit_Yes;
+    m_chip_ptr->getSequencer(m_version)->makeRequest(new_request);
+  }
+
+  // Update the StoreCache
+  m_store_cache.add(subblock);
+
+  // Enqueue the entry
+  StoreBufferEntry entry(subblock, type, pc, access_mode, size, threadID); // FIXME
+  enqueue(entry);
+
+  if(type == CacheRequestType_ATOMIC) {
+    m_seen_atomic = true;
+  }
+
+  processHeadOfQueue();
+}
+
+void StoreBuffer::callBack(const Address& addr, DataBlock& data)
+{
+  DEBUG_MSG(STOREBUFFER_COMP, MedPrio, "callBack");
+  DEBUG_EXPR(STOREBUFFER_COMP, MedPrio, g_eventQueue_ptr->getTime());
+  assert(!isEmpty());
+  assert(m_pending == true);
+  assert(line_address(addr) == addr);
+  assert(line_address(m_pending_address) == addr);
+  assert(line_address(peek().m_subblock.getAddress()) == addr);
+  CacheRequestType type = peek().m_type;
+  int threadID = peek().m_thread;
+  assert((type == CacheRequestType_ST) || (type == CacheRequestType_ATOMIC));
+  m_pending = false;
+
+  // If oldest entry was ATOMIC, perform the callback
+  if(type == CacheRequestType_ST) {
+    // We already performed the call back for the store at insert time
+  } else {
+    // We waited to perform the hitCallback until now for Atomics
+    peek().m_subblock.mergeFrom(data);  // copy the correct bytes from DataBlock into the SubBlock for the Load part of the atomic Load/Store
+    g_system_ptr->getDriver()->hitCallback(m_chip_ptr->getID(), peek().m_subblock, type, threadID);
+    m_seen_atomic = false;
+
+    /// FIXME - record the time spent in the store buffer - split out ST vs ATOMIC
+  }
+  assert(peek().m_subblock.getSize() != 0);
+
+  // Apply the head entry to the datablock
+  peek().m_subblock.mergeTo(data);  // For both the Store and Atomic cases
+
+  // Update the StoreCache
+  m_store_cache.remove(peek().m_subblock);
+
+  // Dequeue the entry from the store buffer
+  dequeue();
+
+  if (isEmpty()) {
+    assert(m_store_cache.isEmpty());
+  }
+
+  if(type == CacheRequestType_ATOMIC) {
+    assert(isEmpty());
+  }
+
+  // See if we can remove any more entries
+  processHeadOfQueue();
+}
+
+void StoreBuffer::processHeadOfQueue()
+{
+  if(!isEmpty() && !m_pending) {
+    StoreBufferEntry& entry = peek();
+    assert(m_pending == false);
+    m_pending = true;
+    m_pending_address = entry.m_subblock.getAddress();
+    CacheMsg request(entry.m_subblock.getAddress(), entry.m_subblock.getAddress(), entry.m_type, entry.m_pc, entry.m_access_mode, entry.m_size, PrefetchBit_No, 0, Address(0), entry.m_thread, 0, false);
+    m_chip_ptr->getSequencer(m_version)->doRequest(request);
+  }
+}
+
+bool StoreBuffer::isReady() const
+{
+  return ((m_size < MAX_ENTRIES) && (!m_seen_atomic));
+}
+
+// Queue implementation methods
+
+StoreBufferEntry& StoreBuffer::peek()
+{
+  return getEntry(m_head);
+}
+
+void StoreBuffer::dequeue()
+{
+  assert(m_size > 0);
+  m_size--;
+  inc_index(m_head);
+}
+
+void StoreBuffer::enqueue(const StoreBufferEntry& entry)
+{
+  //  assert(isReady());
+  (*m_queue_ptr)[m_tail] = entry;
+  m_size++;
+  g_system_ptr->getProfiler()->storeBuffer(m_size, m_store_cache.size());
+  inc_index(m_tail);
+}
+
+StoreBufferEntry& StoreBuffer::getEntry(int index)
+{
+  return (*m_queue_ptr)[index];
+}
+
+void StoreBuffer::print(ostream& out) const
+{
+  out << "[StoreBuffer]";
+}
+