mem: Use the new unbound port reporting mechanism in the mem ports.

There was an add-hoc check added to getAddrRanges, but the other methods
would just segfault if they tried to talk to their peers. This change
wraps all the calls in try blocks and catches the exception which the
peer will throw if it's the default and the port is not actually
connected to anything.

Change-Id: Ie46be0230f33f74305c599b251ca319a65ba008d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/30296
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

diff --git a/src/mem/port.cc b/src/mem/port.cc
index 883b5925684257f98657a2d461087116d15854f6..47e94f4714ec4cc3c9f4d161c9d41aac3dfc2442 100644 (file)
--- a/src/mem/port.cc
+++ b/src/mem/port.cc
@@ -47,11 +47,72 @@
 #include "base/trace.hh"
 #include "sim/sim_object.hh"
 
+namespace
+{
+
+class DefaultMasterPort : public MasterPort
+{
+  protected:
+    [[noreturn]] void
+    blowUp() const
+    {
+        throw UnboundPortException();
+    }
+
+  public:
+    DefaultMasterPort() : MasterPort("default_master_port", nullptr) {}
+
+    // Atomic protocol.
+    Tick recvAtomicSnoop(PacketPtr) override { blowUp(); }
+
+    // Timing protocol.
+    bool recvTimingResp(PacketPtr) override { blowUp(); }
+    void recvTimingSnoopReq(PacketPtr) override { blowUp(); }
+    void recvReqRetry() override { blowUp(); }
+    void recvRetrySnoopResp() override { blowUp(); }
+
+    // Functional protocol.
+    void recvFunctionalSnoop(PacketPtr) override { blowUp(); }
+};
+
+class DefaultSlavePort : public SlavePort
+{
+  protected:
+    [[noreturn]] void
+    blowUp() const
+    {
+        throw UnboundPortException();
+    }
+
+  public:
+    DefaultSlavePort() : SlavePort("default_slave_port", nullptr) {}
+
+    // Atomic protocol.
+    Tick recvAtomic(PacketPtr) override { blowUp(); }
+
+    // Timing protocol.
+    bool recvTimingReq(PacketPtr) override { blowUp(); }
+    bool tryTiming(PacketPtr) override { blowUp(); }
+    bool recvTimingSnoopResp(PacketPtr) override { blowUp(); }
+    void recvRespRetry() override { blowUp(); }
+
+    // Functional protocol.
+    void recvFunctional(PacketPtr) override { blowUp(); }
+
+    // General.
+    AddrRangeList getAddrRanges() const override { return AddrRangeList(); }
+};
+
+DefaultMasterPort defaultMasterPort;
+DefaultSlavePort defaultSlavePort;
+
+} // anonymous namespace
+
 /**
  * Master port
  */
 MasterPort::MasterPort(const std::string& name, SimObject* _owner, PortID _id)
-    : Port(name, _id), _slavePort(NULL), owner(*_owner)
+    : Port(name, _id), _slavePort(&defaultSlavePort), owner(*_owner)
 {
 }
 
@@ -63,10 +124,8 @@ void
 MasterPort::bind(Port &peer)
 {
     auto *slave_port = dynamic_cast<SlavePort *>(&peer);
-    if (!slave_port) {
-        fatal("Attempt to bind port %s to non-slave port %s.",
-                name(), peer.name());
-    }
+    fatal_if(!slave_port, "Can't bind port %s to non-slave port %s.",
+             name(), peer.name());
     // master port keeps track of the slave port
     _slavePort = slave_port;
     Port::bind(peer);
@@ -77,11 +136,10 @@ MasterPort::bind(Port &peer)
 void
 MasterPort::unbind()
 {
-    if (_slavePort == NULL)
-        panic("Attempting to unbind master port %s that is not connected\n",
-              name());
+    panic_if(!isConnected(), "Can't unbind master port %s which is not bound.",
+             name());
     _slavePort->slaveUnbind();
-    _slavePort = nullptr;
+    _slavePort = &defaultSlavePort;
     Port::unbind();
 }
 
@@ -108,8 +166,8 @@ MasterPort::printAddr(Addr a)
  * Slave port
  */
 SlavePort::SlavePort(const std::string& name, SimObject* _owner, PortID id)
-    : Port(name, id), _masterPort(NULL), defaultBackdoorWarned(false),
-    owner(*_owner)
+    : Port(name, id), _masterPort(&defaultMasterPort),
+    defaultBackdoorWarned(false), owner(*_owner)
 {
 }
 
@@ -120,7 +178,7 @@ SlavePort::~SlavePort()
 void
 SlavePort::slaveUnbind()
 {
-    _masterPort = NULL;
+    _masterPort = &defaultMasterPort;
     Port::unbind();
 }
 

diff --git a/src/mem/port.hh b/src/mem/port.hh
index d84e46f207b3120eb98ae282f5cdf0bd570923aa..eadf7f44aa688aff6062c80793354e0511bcf8cd 100644 (file)
--- a/src/mem/port.hh
+++ b/src/mem/port.hh
@@ -258,6 +258,7 @@ class SlavePort : public Port, public AtomicResponseProtocol,
 
   private:
     MasterPort* _masterPort;
+
     bool defaultBackdoorWarned;
 
   protected:
@@ -278,13 +279,7 @@ class SlavePort : public Port, public AtomicResponseProtocol,
     /**
      * Called by the owner to send a range change
      */
-    void
-    sendRangeChange() const
-    {
-        fatal_if(!_masterPort,
-                "%s cannot sendRangeChange() without master port.", name());
-        _masterPort->recvRangeChange();
-    }
+    void sendRangeChange() const { _masterPort->recvRangeChange(); }
 
     /**
      * Get a list of the non-overlapping address ranges the owner is
@@ -316,7 +311,11 @@ class SlavePort : public Port, public AtomicResponseProtocol,
     Tick
     sendAtomicSnoop(PacketPtr pkt)
     {
-        return AtomicResponseProtocol::sendSnoop(_masterPort, pkt);
+        try {
+            return AtomicResponseProtocol::sendSnoop(_masterPort, pkt);
+        } catch (UnboundPortException) {
+            reportUnbound();
+        }
     }
 
   public:
@@ -332,7 +331,11 @@ class SlavePort : public Port, public AtomicResponseProtocol,
     void
     sendFunctionalSnoop(PacketPtr pkt) const
     {
-        FunctionalResponseProtocol::sendSnoop(_masterPort, pkt);
+        try {
+            FunctionalResponseProtocol::sendSnoop(_masterPort, pkt);
+        } catch (UnboundPortException) {
+            reportUnbound();
+        }
     }
 
   public:
@@ -352,7 +355,11 @@ class SlavePort : public Port, public AtomicResponseProtocol,
     bool
     sendTimingResp(PacketPtr pkt)
     {
-        return TimingResponseProtocol::sendResp(_masterPort, pkt);
+        try {
+            return TimingResponseProtocol::sendResp(_masterPort, pkt);
+        } catch (UnboundPortException) {
+            reportUnbound();
+        }
     }
 
     /**
@@ -365,7 +372,11 @@ class SlavePort : public Port, public AtomicResponseProtocol,
     void
     sendTimingSnoopReq(PacketPtr pkt)
     {
-        TimingResponseProtocol::sendSnoopReq(_masterPort, pkt);
+        try {
+            TimingResponseProtocol::sendSnoopReq(_masterPort, pkt);
+        } catch (UnboundPortException) {
+            reportUnbound();
+        }
     }
 
     /**
@@ -375,7 +386,11 @@ class SlavePort : public Port, public AtomicResponseProtocol,
     void
     sendRetryReq()
     {
-        TimingResponseProtocol::sendRetryReq(_masterPort);
+        try {
+            TimingResponseProtocol::sendRetryReq(_masterPort);
+        } catch (UnboundPortException) {
+            reportUnbound();
+        }
     }
 
     /**
@@ -385,7 +400,11 @@ class SlavePort : public Port, public AtomicResponseProtocol,
     void
     sendRetrySnoopResp()
     {
-        TimingResponseProtocol::sendRetrySnoopResp(_masterPort);
+        try {
+            TimingResponseProtocol::sendRetrySnoopResp(_masterPort);
+        } catch (UnboundPortException) {
+            reportUnbound();
+        }
     }
 
   protected:
@@ -422,43 +441,71 @@ class SlavePort : public Port, public AtomicResponseProtocol,
 inline Tick
 MasterPort::sendAtomic(PacketPtr pkt)
 {
-    return AtomicRequestProtocol::send(_slavePort, pkt);
+    try {
+        return AtomicRequestProtocol::send(_slavePort, pkt);
+    } catch (UnboundPortException) {
+        reportUnbound();
+    }
 }
 
 inline Tick
 MasterPort::sendAtomicBackdoor(PacketPtr pkt, MemBackdoorPtr &backdoor)
 {
-    return AtomicRequestProtocol::sendBackdoor(_slavePort, pkt, backdoor);
+    try {
+        return AtomicRequestProtocol::sendBackdoor(_slavePort, pkt, backdoor);
+    } catch (UnboundPortException) {
+        reportUnbound();
+    }
 }
 
 inline void
 MasterPort::sendFunctional(PacketPtr pkt) const
 {
-    return FunctionalRequestProtocol::send(_slavePort, pkt);
+    try {
+        return FunctionalRequestProtocol::send(_slavePort, pkt);
+    } catch (UnboundPortException) {
+        reportUnbound();
+    }
 }
 
 inline bool
 MasterPort::sendTimingReq(PacketPtr pkt)
 {
-    return TimingRequestProtocol::sendReq(_slavePort, pkt);
+    try {
+        return TimingRequestProtocol::sendReq(_slavePort, pkt);
+    } catch (UnboundPortException) {
+        reportUnbound();
+    }
 }
 
 inline bool
 MasterPort::tryTiming(PacketPtr pkt) const
 {
-    return TimingRequestProtocol::trySend(_slavePort, pkt);
+    try {
+        return TimingRequestProtocol::trySend(_slavePort, pkt);
+    } catch (UnboundPortException) {
+        reportUnbound();
+    }
 }
 
 inline bool
 MasterPort::sendTimingSnoopResp(PacketPtr pkt)
 {
-    return TimingRequestProtocol::sendSnoopResp(_slavePort, pkt);
+    try {
+        return TimingRequestProtocol::sendSnoopResp(_slavePort, pkt);
+    } catch (UnboundPortException) {
+        reportUnbound();
+    }
 }
 
 inline void
 MasterPort::sendRetryResp()
 {
-    TimingRequestProtocol::sendRetryResp(_slavePort);
+    try {
+        TimingRequestProtocol::sendRetryResp(_slavePort);
+    } catch (UnboundPortException) {
+        reportUnbound();
+    }
 }
 
 #endif //__MEM_PORT_HH__