Yan Lee has uploaded this change for review. (
https://gem5-review.googlesource.com/c/public/gem5/+/71538?usp=email )
Change subject: mem: port: add TracingExtension for debug purpose
......................................................................
mem: port: add TracingExtension for debug purpose
TracingExtension contains a stack recording the port names
passed through of the Packet. The target receiving the Packet
can dump out the whole path of this Packet for the debug purpose.
This mechanism can be enabled with the debug flag PortTrace.
Change-Id: Ic11e708b35fdddc4f4b786d91b35fd4def08948c
---
M src/mem/SConscript
M src/mem/port.cc
M src/mem/port.hh
3 files changed, 92 insertions(+), 6 deletions(-)
diff --git a/src/mem/SConscript b/src/mem/SConscript
index 351f24e..6e017e0 100644
--- a/src/mem/SConscript
+++ b/src/mem/SConscript
@@ -151,6 +151,7 @@
DebugFlag('MMU')
DebugFlag('MemoryAccess')
DebugFlag('PacketQueue')
+DebugFlag("PortTrace")
DebugFlag('ResponsePort')
DebugFlag('StackDist')
DebugFlag("DRAMSim2")
diff --git a/src/mem/port.cc b/src/mem/port.cc
index 2a253b9..2f754c8 100644
--- a/src/mem/port.cc
+++ b/src/mem/port.cc
@@ -45,6 +45,7 @@
#include "mem/port.hh"
#include "base/trace.hh"
+#include "debug/PortTrace.hh"
#include "debug/ResponsePort.hh"
#include "sim/sim_object.hh"
@@ -186,6 +187,29 @@
sendFunctional(&pkt);
}
+void
+RequestPort::addTrace(PacketPtr pkt) const
+{
+ if (!gem5::debug::PortTrace || !pkt)
+ return;
+ auto ext = pkt->getExtension<TracingExtension>();
+ if (!ext) {
+ ext = std::make_shared<TracingExtension>();
+ pkt->setExtension(ext);
+ }
+ ext->add(name(), _responsePort->name());
+}
+
+void
+RequestPort::removeTrace(PacketPtr pkt) const
+{
+ if (!gem5::debug::PortTrace || !pkt)
+ return;
+ auto ext = pkt->getExtension<TracingExtension>();
+ panic_if(!ext, "There is no TracingExtension in the packet.");
+ ext->remove();
+}
+
/**
* Response port
*/
diff --git a/src/mem/port.hh b/src/mem/port.hh
index a3acffc..2555706 100644
--- a/src/mem/port.hh
+++ b/src/mem/port.hh
@@ -46,6 +46,10 @@
#ifndef __MEM_PORT_HH__
#define __MEM_PORT_HH__
+#include <memory>
+#include <stack>
+#include <string>
+
#include "base/addr_range.hh"
#include "mem/packet.hh"
#include "mem/protocol/atomic.hh"
@@ -65,6 +69,43 @@
class ResponsePort;
/**
+ * TracingExtension is an Extension of the Packet for recording the trace
+ * of the Packet. The stack in the TracingExtension holds the name of the
+ * ports that the Packet has passed through.
+ */
+class TracingExtension : public gem5::Extension<Packet, TracingExtension>
+{
+ public:
+ TracingExtension() = default;
+ TracingExtension(const std::stack<std::string>& q) { trace_ = q; }
+
+ std::unique_ptr<ExtensionBase> clone() const override
+ {
+ return std::make_unique<TracingExtension>(trace_);
+ }
+
+ void
+ add(std::string request_port, std::string response_port)
+ {
+ trace_.push(request_port);
+ trace_.push(response_port);
+ }
+
+ void
+ remove()
+ {
+ trace_.pop(); // Remove the response port name.
+ trace_.pop(); // Remove the request port name.
+ }
+
+ bool empty() { return trace_.empty(); }
+ std::stack<std::string>& getTrace() { return trace_; }
+
+ private:
+ std::stack<std::string> trace_;
+};
+
+/**
* A RequestPort is a specialisation of a Port, which
* implements the default protocol for the three different level of
* transport functions. In addition to the basic functionality of
@@ -266,6 +307,10 @@
{
panic("%s was not expecting a snoop retry.\n", name());
}
+
+ private:
+ void addTrace(PacketPtr pkt) const;
+ void removeTrace(PacketPtr pkt) const;
};
class [[deprecated]] MasterPort : public RequestPort
@@ -393,7 +438,11 @@
sendTimingResp(PacketPtr pkt)
{
try {
- return TimingResponseProtocol::sendResp(_requestPort, pkt);
+ _requestPort->removeTrace(pkt);
+ bool succ = TimingResponseProtocol::sendResp(_requestPort,
pkt);
+ if (!succ)
+ _requestPort->addTrace(pkt);
+ return succ;
} catch (UnboundPortException) {
reportUnbound();
}
@@ -487,7 +536,10 @@
RequestPort::sendAtomic(PacketPtr pkt)
{
try {
- return AtomicRequestProtocol::send(_responsePort, pkt);
+ addTrace(pkt);
+ Tick tick = AtomicRequestProtocol::send(_responsePort, pkt);
+ removeTrace(pkt);
+ return tick;
} catch (UnboundPortException) {
reportUnbound();
}
@@ -497,8 +549,11 @@
RequestPort::sendAtomicBackdoor(PacketPtr pkt, MemBackdoorPtr &backdoor)
{
try {
- return AtomicRequestProtocol::sendBackdoor(_responsePort,
- pkt, backdoor);
+ addTrace(pkt);
+ Tick tick = AtomicRequestProtocol::sendBackdoor(_responsePort,
+ pkt, backdoor);
+ removeTrace(pkt);
+ return tick;
} catch (UnboundPortException) {
reportUnbound();
}
@@ -508,7 +563,9 @@
RequestPort::sendFunctional(PacketPtr pkt) const
{
try {
- return FunctionalRequestProtocol::send(_responsePort, pkt);
+ addTrace(pkt);
+ FunctionalRequestProtocol::send(_responsePort, pkt);
+ removeTrace(pkt);
} catch (UnboundPortException) {
reportUnbound();
}
@@ -530,7 +587,11 @@
RequestPort::sendTimingReq(PacketPtr pkt)
{
try {
- return TimingRequestProtocol::sendReq(_responsePort, pkt);
+ addTrace(pkt);
+ bool succ = TimingRequestProtocol::sendReq(_responsePort, pkt);
+ if (!succ)
+ removeTrace(pkt);
+ return succ;
} catch (UnboundPortException) {
reportUnbound();
}
--
To view, visit
https://gem5-review.googlesource.com/c/public/gem5/+/71538?usp=email
To unsubscribe, or for help writing mail filters, visit
https://gem5-review.googlesource.com/settings?usp=email
Gerrit-MessageType: newchange
Gerrit-Project: public/gem5
Gerrit-Branch: develop
Gerrit-Change-Id: Ic11e708b35fdddc4f4b786d91b35fd4def08948c
Gerrit-Change-Number: 71538
Gerrit-PatchSet: 1
Gerrit-Owner: Yan Lee <yan...@google.com>
_______________________________________________
gem5-dev mailing list -- gem5-dev@gem5.org
To unsubscribe send an email to gem5-dev-le...@gem5.org
