mem: Move trace functionality from the CommMonitor to a probe

This changeset moves the access trace functionality from the
CommMonitor into a separate probe. The probe can be hooked up to any
component that exports probe points of the type ProbePoints::Packet.

This patch moves the dependency on Google's Protocol Buffers library
from the CommMonitor to the MemTraceProbe, which means that the
CommMonitor (including stack distance profiling) no long depends on
it.

4 files changed, 239 insertions, 0 deletions

diff --git a/src/mem/probes/MemTraceProbe.py b/src/mem/probes/MemTraceProbe.py
new file mode 100644
index 000000000..971765eb4
--- /dev/null
+++ b/src/mem/probes/MemTraceProbe.py
@@ -0,0 +1,51 @@
+# Copyright (c) 2014-2015 ARM Limited
+# All rights reserved.
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
+# 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: Andreas Sandberg
+
+from m5.params import *
+from m5.proxy import *
+from BaseMemProbe import BaseMemProbe
+
+class MemTraceProbe(BaseMemProbe):
+    type = 'MemTraceProbe'
+    cxx_header = "mem/probes/mem_trace.hh"
+
+    # Boolean to compress the trace or not.
+    trace_compress = Param.Bool(True, "Enable trace compression")
+
+    # packet trace output file, disabled by default
+    trace_file = Param.String("", "Packet trace output file")
+
diff --git a/src/mem/probes/SConscript b/src/mem/probes/SConscript
index 7391545fb..78423c5d6 100644
--- a/src/mem/probes/SConscript
+++ b/src/mem/probes/SConscript
@@ -44,3 +44,8 @@ Source('base.cc')
 
 SimObject('StackDistProbe.py')
 Source('stack_dist.cc')
+
+# Packet tracing requires protobuf support
+if env['HAVE_PROTOBUF']:
+    SimObject('MemTraceProbe.py')
+    Source('mem_trace.cc')
diff --git a/src/mem/probes/mem_trace.cc b/src/mem/probes/mem_trace.cc
new file mode 100644
index 000000000..6bf6f7f77
--- /dev/null
+++ b/src/mem/probes/mem_trace.cc
@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2015 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * 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: Andreas Hansson
+ *          Andreas Sandberg
+ */
+
+#include "mem/probes/mem_trace.hh"
+
+#include "base/callback.hh"
+#include "base/output.hh"
+#include "params/MemTraceProbe.hh"
+#include "proto/packet.pb.h"
+
+MemTraceProbe::MemTraceProbe(MemTraceProbeParams *p)
+    : BaseMemProbe(p),
+      traceStream(nullptr)
+{
+    std::string filename;
+    if (p->trace_file != "") {
+        // If the trace file is not specified as an absolute path,
+        // append the current simulation output directory
+        filename = simout.resolve(p->trace_file);
+
+        const std::string suffix = ".gz";
+        // If trace_compress has been set, check the suffix. Append
+        // accordingly.
+        if (p->trace_compress &&
+            filename.compare(filename.size() - suffix.size(), suffix.size(),
+                             suffix) != 0)
+            filename = filename + suffix;
+    } else {
+        // Generate a filename from the name of the SimObject. Append .trc
+        // and .gz if we want compression enabled.
+        filename = simout.resolve(name() + ".trc" +
+                                  (p->trace_compress ? ".gz" : ""));
+    }
+
+    traceStream = new ProtoOutputStream(filename);
+
+    // Create a protobuf message for the header and write it to
+    // the stream
+    ProtoMessage::PacketHeader header_msg;
+    header_msg.set_obj_id(name());
+    header_msg.set_tick_freq(SimClock::Frequency);
+    traceStream->write(header_msg);
+
+    // Register a callback to compensate for the destructor not
+    // being called. The callback forces the stream to flush and
+    // closes the output file.
+    registerExitCallback(
+        new MakeCallback<MemTraceProbe, &MemTraceProbe::closeStreams>(this));
+}
+
+void
+MemTraceProbe::closeStreams()
+{
+    if (traceStream != NULL)
+        delete traceStream;
+}
+
+void
+MemTraceProbe::handleRequest(const PacketPtr &pkt)
+{
+    ProtoMessage::Packet pkt_msg;
+
+    pkt_msg.set_tick(curTick());
+    pkt_msg.set_cmd(pkt->cmdToIndex());
+    pkt_msg.set_flags(pkt->req->getFlags());
+    pkt_msg.set_addr(pkt->getAddr());
+    pkt_msg.set_size(pkt->getSize());
+
+    traceStream->write(pkt_msg);
+}
+
+
+MemTraceProbe *
+MemTraceProbeParams::create()
+{
+    return new MemTraceProbe(this);
+}
diff --git a/src/mem/probes/mem_trace.hh b/src/mem/probes/mem_trace.hh
new file mode 100644
index 000000000..93c6067ae
--- /dev/null
+++ b/src/mem/probes/mem_trace.hh
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2015 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
+ * 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: Andreas Sandberg
+ */
+
+#ifndef __MEM_PROBES_STACK_DIST_HH__
+#define __MEM_PROBES_STACK_DIST_HH__
+
+#include "mem/packet.hh"
+#include "mem/probes/base.hh"
+#include "proto/protoio.hh"
+
+struct MemTraceProbeParams;
+
+class MemTraceProbe : public BaseMemProbe
+{
+  public:
+    MemTraceProbe(MemTraceProbeParams *params);
+
+  protected:
+    void handleRequest(const PacketPtr &pkt) M5_ATTR_OVERRIDE;
+
+    /**
+     * Callback to flush and close all open output streams on exit. If
+     * we were calling the destructor it could be done there.
+     */
+    void closeStreams();
+
+  protected:
+
+    /** Trace output stream */
+    ProtoOutputStream *traceStream;
+};
+
+#endif //__MEM_PROBES_STACK_DIST_HH__