mem-ruby: Allow Ruby to use all replacement policies in Classic

Add support in Ruby to use all replacement policies in Classic.
Furthermore, if new replacement policies are added to the
Classic system, the Ruby system will recognize new policies
without any other changes in Ruby system. The following list
all the major changes:

  * Make Ruby cache entries (AbstractCacheEntry) inherit from
    Classic cache entries (ReplaceableEntry). By doing this,
    replacement policies can use cache entries from Ruby caches.
    AccessPermission and print function are moved from
    AbstractEntry to AbstractCacheEntry, so AbstractEntry is no
    longer needed.

  * DirectoryMemory and all SLICC files are changed to use
    AbstractCacheEntry as their cache entry interface. So do the
    python files in mem/slicc/ast which check the entry
    interface.

  * "main='false'" argument is added to the protocol files where
    the DirectoryEntry is defined. This change helps
    differentiate DirectoryEntry from CacheEntry because they are
    both the instances of AbstractCacheEntry now.

  * Use BaseReplacementPolicy in Ruby caches instead of
    AbstractReplacementPolicy so that Ruby caches will recognize
    the replacement policies from Classic.

  * Add getLastAccess() and useOccupancy() function to Classic
    system so that Ruby caches can use them. Move lastTouchTick
    to ReplacementData struct because it's needed by
    getLastAccess() to return the correct value.

  * Add a 2-dimensional array of ReplacementData in Ruby caches
    to store information for different replacement policies. Note
    that, unlike Classic caches, where policy information is
    stored in cache entries, the policy information needs to be
    stored in a new 2-dimensional array. This is due to Ruby
    caches deleting the cache entry every time the corresponding
    cache line get evicted.

Change-Id: Idff6fdd2102a552c103e9d5f31f779aae052943f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20879
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

5 files changed, 27 insertions, 125 deletions

diff --git a/src/mem/ruby/slicc_interface/AbstractCacheEntry.cc b/src/mem/ruby/slicc_interface/AbstractCacheEntry.cc
index 00dfc6c64..b98425d7e 100644
--- a/src/mem/ruby/slicc_interface/AbstractCacheEntry.cc
+++ b/src/mem/ruby/slicc_interface/AbstractCacheEntry.cc
@@ -31,21 +31,29 @@
 #include "base/trace.hh"
 #include "debug/RubyCache.hh"
 
-AbstractCacheEntry::AbstractCacheEntry()
+AbstractCacheEntry::AbstractCacheEntry() : ReplaceableEntry()
 {
     m_Permission = AccessPermission_NotPresent;
     m_Address = 0;
     m_locked = -1;
+    m_last_touch_tick = 0;
 }
 
 AbstractCacheEntry::~AbstractCacheEntry()
 {
 }
 
+// Get cache permission
+AccessPermission
+AbstractCacheEntry::getPermission() const
+{
+    return m_Permission;
+}
+
 void
 AbstractCacheEntry::changePermission(AccessPermission new_perm)
 {
-    AbstractEntry::changePermission(new_perm);
+    m_Permission = new_perm;
     if ((new_perm == AccessPermission_Invalid) ||
         (new_perm == AccessPermission_NotPresent)) {
         m_locked = -1;
diff --git a/src/mem/ruby/slicc_interface/AbstractCacheEntry.hh b/src/mem/ruby/slicc_interface/AbstractCacheEntry.hh
index c943c75d0..0519b3f7d 100644
--- a/src/mem/ruby/slicc_interface/AbstractCacheEntry.hh
+++ b/src/mem/ruby/slicc_interface/AbstractCacheEntry.hh
@@ -36,21 +36,28 @@
 #include <iostream>
 
 #include "base/logging.hh"
+#include "mem/cache/replacement_policies/replaceable_entry.hh"
 #include "mem/ruby/common/Address.hh"
 #include "mem/ruby/protocol/AccessPermission.hh"
-#include "mem/ruby/slicc_interface/AbstractEntry.hh"
 
 class DataBlock;
 
-class AbstractCacheEntry : public AbstractEntry
+class AbstractCacheEntry : public ReplaceableEntry
 {
+  private:
+    // The last access tick for the cache entry.
+    Tick m_last_touch_tick;
+
   public:
     AbstractCacheEntry();
     virtual ~AbstractCacheEntry() = 0;
 
     // Get/Set permission of the entry
+    AccessPermission getPermission() const;
     void changePermission(AccessPermission new_perm);
 
+    virtual void print(std::ostream& out) const = 0;
+
     // The methods below are those called by ruby runtime, add when it
     // is absolutely necessary and should all be virtual function.
     virtual DataBlock& getDataBlk()
@@ -68,22 +75,20 @@ class AbstractCacheEntry : public AbstractEntry
     void clearLocked();
     bool isLocked(int context) const;
 
-    void setSetIndex(uint32_t s) { m_set_index = s; }
-    uint32_t getSetIndex() const { return m_set_index; }
-
-    void setWayIndex(uint32_t s) { m_way_index = s; }
-    uint32_t getWayIndex() const { return m_way_index; }
-
     // Address of this block, required by CacheMemory
     Addr m_Address;
     // Holds info whether the address is locked.
     // Required for implementing LL/SC operations.
     int m_locked;
 
-  private:
-    // Set and way coordinates of the entry within the cache memory object.
-    uint32_t m_set_index;
-    uint32_t m_way_index;
+    AccessPermission m_Permission; // Access permission for this
+                                   // block, required by CacheMemory
+
+    // Get the last access Tick.
+    Tick getLastAccess() { return m_last_touch_tick; }
+
+    // Set the last access Tick.
+    void setLastAccess(Tick tick) { m_last_touch_tick = tick; }
 };
 
 inline std::ostream&
diff --git a/src/mem/ruby/slicc_interface/AbstractEntry.cc b/src/mem/ruby/slicc_interface/AbstractEntry.cc
deleted file mode 100644
index 51f16df6a..000000000
--- a/src/mem/ruby/slicc_interface/AbstractEntry.cc
+++ /dev/null
@@ -1,50 +0,0 @@
-/*
- * 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.
- */
-
-#include "mem/ruby/slicc_interface/AbstractEntry.hh"
-
-AbstractEntry::AbstractEntry()
-{
-    m_Permission = AccessPermission_NotPresent;
-}
-
-AbstractEntry::~AbstractEntry()
-{
-}
-
-AccessPermission
-AbstractEntry::getPermission() const
-{
-    return m_Permission;
-}
-
-void
-AbstractEntry::changePermission(AccessPermission new_perm)
-{
-    m_Permission = new_perm;
-}
diff --git a/src/mem/ruby/slicc_interface/AbstractEntry.hh b/src/mem/ruby/slicc_interface/AbstractEntry.hh
deleted file mode 100644
index a75055f5e..000000000
--- a/src/mem/ruby/slicc_interface/AbstractEntry.hh
+++ /dev/null
@@ -1,60 +0,0 @@
-/*
- * 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.
- */
-
-#ifndef __MEM_RUBY_SLICC_INTERFACE_ABSTRACTENTRY_HH__
-#define __MEM_RUBY_SLICC_INTERFACE_ABSTRACTENTRY_HH__
-
-#include <iostream>
-
-#include "mem/ruby/protocol/AccessPermission.hh"
-
-class AbstractEntry
-{
-  public:
-    AbstractEntry();
-    virtual ~AbstractEntry() = 0;
-
-    // Get/Set permission of the entry
-    AccessPermission getPermission() const;
-    void changePermission(AccessPermission new_perm);
-
-    virtual void print(std::ostream& out) const = 0;
-
-    AccessPermission m_Permission; // Access permission for this
-                                   // block, required by CacheMemory
-};
-
-inline std::ostream&
-operator<<(std::ostream& out, const AbstractEntry& obj)
-{
-    obj.print(out);
-    out << std::flush;
-    return out;
-}
-
-#endif // __MEM_RUBY_SLICC_INTERFACE_ABSTRACTENTRY_HH__
diff --git a/src/mem/ruby/slicc_interface/SConscript b/src/mem/ruby/slicc_interface/SConscript
index 2d00fb7fe..d8d931c63 100644
--- a/src/mem/ruby/slicc_interface/SConscript
+++ b/src/mem/ruby/slicc_interface/SConscript
@@ -36,6 +36,5 @@ if env['PROTOCOL'] == 'None':
 SimObject('Controller.py')
 
 Source('AbstractController.cc')
-Source('AbstractEntry.cc')
 Source('AbstractCacheEntry.cc')
 Source('RubyRequest.cc')