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diff --git a/src/sim/futex_map.hh b/src/sim/futex_map.hh
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+/*
+ * Copyright (c) 2017 Advanced Micro Devices, Inc.
+ * 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: Brandon Potter
+ *          Steve Reinhardt
+ *          Alexandru Dutu
+ */
+
+#ifndef __FUTEX_MAP_HH__
+#define __FUTEX_MAP_HH__
+
+#include <unordered_map>
+
+#include <cpu/thread_context.hh>
+
+/**
+ * FutexKey class defines an unique identifier for a particular futex in the
+ * system. The tgid and an address are the unique values needed as the key.
+ */
+class FutexKey {
+  public:
+    uint64_t addr;
+    uint64_t tgid;
+
+    FutexKey(uint64_t addr_in, uint64_t tgid_in)
+        : addr(addr_in), tgid(tgid_in)
+    {
+    }
+
+    bool
+    operator==(const FutexKey &in) const
+    {
+        return addr == in.addr && tgid == in.tgid;
+    }
+};
+
+namespace std {
+    /**
+     * The unordered_map structure needs the parenthesis operator defined for
+     * std::hash if a user defined key is used. Our key is is user defined
+     * so we need to provide the hash functor.
+     */
+    template <>
+    struct hash<FutexKey>
+    {
+        size_t operator()(const FutexKey& in) const
+        {
+            size_t hash = 65521;
+            for (int i = 0; i < sizeof(uint64_t) / sizeof(size_t); i++) {
+                hash ^= (size_t)(in.addr >> sizeof(size_t) * i) ^
+                        (size_t)(in.tgid >> sizeof(size_t) * i);
+            }
+            return hash;
+        }
+    };
+}
+
+typedef std::list<ThreadContext *> ThreadContextList;
+
+/**
+ * FutexMap class holds a map of all futexes used in the system
+ */
+class FutexMap : public std::unordered_map<FutexKey, ThreadContextList>
+{
+  public:
+    /** Inserts a futex into the map with one waiting TC */
+    void
+    suspend(Addr addr, uint64_t tgid, ThreadContext *tc)
+    {
+        FutexKey key(addr, tgid);
+        auto it = find(key);
+
+        if (it == end()) {
+            ThreadContextList tcList {tc};
+            insert({key, tcList});
+        } else {
+            it->second.push_back(tc);
+        }
+
+        /** Suspend the thread context */
+        tc->suspend();
+    }
+
+    /** Wakes up at most count waiting threads on a futex */
+    int
+    wakeup(Addr addr, uint64_t tgid, int count)
+    {
+        FutexKey key(addr, tgid);
+        auto it = find(key);
+
+        if (it == end())
+            return 0;
+
+        int woken_up = 0;
+        auto &tcList = it->second;
+
+        while (!tcList.empty() && woken_up < count) {
+            tcList.front()->activate();
+            tcList.pop_front();
+            woken_up++;
+        }
+
+        if (tcList.empty())
+            erase(it);
+
+        return woken_up;
+    }
+
+};
+
+#endif // __FUTEX_MAP_HH__