src/mem/mem_checker_monitor.cc - public/gem5 - Git at Google

 /*
  * Copyright (c) 2012-2014 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: Thomas Grass
  *          Andreas Hansson
  *          Marco Elver
  */

 #include "mem/mem_checker_monitor.hh"

 #include <memory>

 #include "base/logging.hh"
 #include "base/output.hh"
 #include "base/trace.hh"
 #include "debug/MemCheckerMonitor.hh"

 MemCheckerMonitor::MemCheckerMonitor(Params* params)
     : MemObject(params),
       masterPort(name() + "-master", *this),
       slavePort(name() + "-slave", *this),
       warnOnly(params->warn_only),
       memchecker(params->memchecker)
 {}

 MemCheckerMonitor::~MemCheckerMonitor()
 {}

 MemCheckerMonitor*
 MemCheckerMonitorParams::create()
 {
     return new MemCheckerMonitor(this);
 }

 void
 MemCheckerMonitor::init()
 {
     // make sure both sides of the monitor are connected
     if (!slavePort.isConnected() || !masterPort.isConnected())
         fatal("Communication monitor is not connected on both sides.\n");
 }

 BaseMasterPort&
 MemCheckerMonitor::getMasterPort(const std::string& if_name, PortID idx)
 {
     if (if_name == "master" || if_name == "mem_side") {
         return masterPort;
     } else {
         return MemObject::getMasterPort(if_name, idx);
     }
 }

 BaseSlavePort&
 MemCheckerMonitor::getSlavePort(const std::string& if_name, PortID idx)
 {
     if (if_name == "slave" || if_name == "cpu_side") {
         return slavePort;
     } else {
         return MemObject::getSlavePort(if_name, idx);
     }
 }

 void
 MemCheckerMonitor::recvFunctional(PacketPtr pkt)
 {
     Addr addr = pkt->getAddr();
     unsigned size = pkt->getSize();

     // Conservatively reset this address-range. Alternatively we could try to
     // update the values seen by the memchecker, however, there may be other
     // reads/writes to these location from other devices we do not see.
     memchecker->reset(addr, size);

     masterPort.sendFunctional(pkt);

     DPRINTF(MemCheckerMonitor,
             "Forwarded functional access: addr = %#llx, size = %d\n",
             addr, size);
 }

 void
 MemCheckerMonitor::recvFunctionalSnoop(PacketPtr pkt)
 {
     Addr addr = pkt->getAddr();
     unsigned size = pkt->getSize();

     // See above.
     memchecker->reset(addr, size);

     slavePort.sendFunctionalSnoop(pkt);

     DPRINTF(MemCheckerMonitor,
             "Received functional snoop: addr = %#llx, size = %d\n",
             addr, size);
 }

 Tick
 MemCheckerMonitor::recvAtomic(PacketPtr pkt)
 {
     panic("Atomic not supported");
 }

 Tick
 MemCheckerMonitor::recvAtomicSnoop(PacketPtr pkt)
 {
     panic("Atomic not supported");
 }

 bool
 MemCheckerMonitor::recvTimingReq(PacketPtr pkt)
 {
     // should always see a request
     assert(pkt->isRequest());

     // Store relevant fields of packet, because packet may be modified
     // or even deleted when sendTiming() is called.
     //
     // For reads we are only interested in real reads, and not prefetches, as
     // it is not guaranteed that the prefetch returns any useful data.
     bool is_read = pkt->isRead() && !pkt->req->isPrefetch();
     bool is_write = pkt->isWrite();
     unsigned size = pkt->getSize();
     Addr addr = pkt->getAddr();
     bool expects_response = pkt->needsResponse() && !pkt->cacheResponding();
     std::unique_ptr<uint8_t[]> pkt_data;
     MemCheckerMonitorSenderState* state = NULL;

     if (expects_response && is_write) {
         // On receipt of a request, only need to allocate pkt_data if this is a
         // write. For reads, we have no data yet, so it doesn't make sense to
         // allocate.
         pkt_data.reset(new uint8_t[size]);
         pkt->writeData(pkt_data.get());
     }

     // If a cache miss is served by a cache, a monitor near the memory
     // would see a request which needs a response, but this response
     // would not come back from the memory. Therefore
     // we additionally have to check the inhibit flag.
     if (expects_response && (is_read || is_write)) {
         state = new MemCheckerMonitorSenderState(0);
         pkt->pushSenderState(state);
     }

     // Attempt to send the packet
     bool successful = masterPort.sendTimingReq(pkt);

     // If not successful, restore the sender state
     if (!successful && expects_response && (is_read || is_write)) {
         delete pkt->popSenderState();
     }

     if (successful && expects_response) {
         if (is_read) {
             MemChecker::Serial serial = memchecker->startRead(curTick(),
                                                               addr,
                                                               size);

             // At the time where we push the sender-state, we do not yet know
             // the serial the MemChecker class will assign to this request. We
             // cannot call startRead at the time we push the sender-state, as
             // the masterPort may not be successful in executing sendTimingReq,
             // and in case of a failure, we must not modify the state of the
             // MemChecker.
             //
             // Once we know that sendTimingReq was successful, we can set the
             // serial of the newly constructed sender-state. This is legal, as
             // we know that nobody else will touch nor is responsible for
             // deletion of our sender-state.
             state->serial = serial;

             DPRINTF(MemCheckerMonitor,
                     "Forwarded read request: serial = %d, addr = %#llx, "
                     "size = %d\n",
                     serial, addr, size);
         } else if (is_write) {
             MemChecker::Serial serial = memchecker->startWrite(curTick(),
                                                                addr,
                                                                size,
                                                                pkt_data.get());

             state->serial = serial;

             DPRINTF(MemCheckerMonitor,
                     "Forwarded write request: serial = %d, addr = %#llx, "
                     "size = %d\n",
                     serial, addr, size);
         } else {
             DPRINTF(MemCheckerMonitor,
                     "Forwarded non read/write request: addr = %#llx\n", addr);
         }
     } else if (successful) {
         DPRINTF(MemCheckerMonitor,
                 "Forwarded request marked for cache response: addr = %#llx\n",
                 addr);
     }

     return successful;
 }

 bool
 MemCheckerMonitor::recvTimingResp(PacketPtr pkt)
 {
     // should always see responses
     assert(pkt->isResponse());

     // Store relevant fields of packet, because packet may be modified
     // or even deleted when sendTiming() is called.
     bool is_read = pkt->isRead() && !pkt->req->isPrefetch();
     bool is_write = pkt->isWrite();
     bool is_failed_LLSC = pkt->isLLSC() && pkt->req->getExtraData() == 0;
     unsigned size = pkt->getSize();
     Addr addr = pkt->getAddr();
     std::unique_ptr<uint8_t[]> pkt_data;
     MemCheckerMonitorSenderState* received_state = NULL;

     if (is_read) {
         // On receipt of a response, only need to allocate pkt_data if this is
         // a read. For writes, we have already given the MemChecker the data on
         // the request, so it doesn't make sense to allocate on write.
         pkt_data.reset(new uint8_t[size]);
         pkt->writeData(pkt_data.get());
     }

     if (is_read || is_write) {
         received_state =
             dynamic_cast<MemCheckerMonitorSenderState*>(pkt->senderState);

         // Restore initial sender state
         panic_if(received_state == NULL,
                  "Monitor got a response without monitor sender state\n");

         // Restore the state
         pkt->senderState = received_state->predecessor;
     }

     // Attempt to send the packet
     bool successful = slavePort.sendTimingResp(pkt);

     // If packet successfully send, complete transaction in MemChecker
     // instance, and delete sender state, otherwise restore state.
     if (successful) {
         if (is_read) {
             DPRINTF(MemCheckerMonitor,
                     "Received read response: serial = %d, addr = %#llx, "
                     "size = %d\n",
                     received_state->serial, addr, size);

             bool result = memchecker->completeRead(received_state->serial,
                                                    curTick(),
                                                    addr,
                                                    size,
                                                    pkt_data.get());

             if (!result) {
                 warn("%s: read of %#llx @ cycle %d failed:\n%s\n",
                      name(),
                      addr, curTick(),
                      memchecker->getErrorMessage().c_str());

                 panic_if(!warnOnly, "MemChecker violation!");
             }

             delete received_state;
         } else if (is_write) {
             DPRINTF(MemCheckerMonitor,
                     "Received write response: serial = %d, addr = %#llx, "
                     "size = %d\n",
                     received_state->serial, addr, size);

             if (is_failed_LLSC) {
                 // The write was not successful, let MemChecker know.
                 memchecker->abortWrite(received_state->serial,
                                        addr,
                                        size);
             } else {
                 memchecker->completeWrite(received_state->serial,
                                           curTick(),
                                           addr,
                                           size);
             }

             delete received_state;
         } else {
             DPRINTF(MemCheckerMonitor,
                     "Received non read/write response: addr = %#llx\n", addr);
         }
     } else if (is_read || is_write) {
         // Don't delete anything and let the packet look like we
         // did not touch it
         pkt->senderState = received_state;
     }

     return successful;
 }

 void
 MemCheckerMonitor::recvTimingSnoopReq(PacketPtr pkt)
 {
     slavePort.sendTimingSnoopReq(pkt);
 }

 bool
 MemCheckerMonitor::recvTimingSnoopResp(PacketPtr pkt)
 {
     return masterPort.sendTimingSnoopResp(pkt);
 }

 bool
 MemCheckerMonitor::isSnooping() const
 {
     // check if the connected master port is snooping
     return slavePort.isSnooping();
 }

 AddrRangeList
 MemCheckerMonitor::getAddrRanges() const
 {
     // get the address ranges of the connected slave port
     return masterPort.getAddrRanges();
 }

 void
 MemCheckerMonitor::recvReqRetry()
 {
     slavePort.sendRetryReq();
 }

 void
 MemCheckerMonitor::recvRespRetry()
 {
     masterPort.sendRetryResp();
 }

 void
 MemCheckerMonitor::recvRangeChange()
 {
     slavePort.sendRangeChange();
 }
	/*
	* Copyright (c) 2012-2014 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: Thomas Grass
	* Andreas Hansson
	* Marco Elver
	*/

	#include "mem/mem_checker_monitor.hh"

	#include <memory>

	#include "base/logging.hh"
	#include "base/output.hh"
	#include "base/trace.hh"
	#include "debug/MemCheckerMonitor.hh"

	MemCheckerMonitor::MemCheckerMonitor(Params* params)
	: MemObject(params),
	masterPort(name() + "-master", *this),
	slavePort(name() + "-slave", *this),
	warnOnly(params->warn_only),
	memchecker(params->memchecker)
	{}

	MemCheckerMonitor::~MemCheckerMonitor()
	{}

	MemCheckerMonitor*
	MemCheckerMonitorParams::create()
	{
	return new MemCheckerMonitor(this);
	}

	void
	MemCheckerMonitor::init()
	{
	// make sure both sides of the monitor are connected
	if (!slavePort.isConnected() \|\| !masterPort.isConnected())
	fatal("Communication monitor is not connected on both sides.\n");
	}

	BaseMasterPort&
	MemCheckerMonitor::getMasterPort(const std::string& if_name, PortID idx)
	{
	if (if_name == "master" \|\| if_name == "mem_side") {
	return masterPort;
	} else {
	return MemObject::getMasterPort(if_name, idx);
	}
	}

	BaseSlavePort&
	MemCheckerMonitor::getSlavePort(const std::string& if_name, PortID idx)
	{
	if (if_name == "slave" \|\| if_name == "cpu_side") {
	return slavePort;
	} else {
	return MemObject::getSlavePort(if_name, idx);
	}
	}

	void
	MemCheckerMonitor::recvFunctional(PacketPtr pkt)
	{
	Addr addr = pkt->getAddr();
	unsigned size = pkt->getSize();

	// Conservatively reset this address-range. Alternatively we could try to
	// update the values seen by the memchecker, however, there may be other
	// reads/writes to these location from other devices we do not see.
	memchecker->reset(addr, size);

	masterPort.sendFunctional(pkt);

	DPRINTF(MemCheckerMonitor,
	"Forwarded functional access: addr = %#llx, size = %d\n",
	addr, size);
	}

	void
	MemCheckerMonitor::recvFunctionalSnoop(PacketPtr pkt)
	{
	Addr addr = pkt->getAddr();
	unsigned size = pkt->getSize();

	// See above.
	memchecker->reset(addr, size);

	slavePort.sendFunctionalSnoop(pkt);

	DPRINTF(MemCheckerMonitor,
	"Received functional snoop: addr = %#llx, size = %d\n",
	addr, size);
	}

	Tick
	MemCheckerMonitor::recvAtomic(PacketPtr pkt)
	{
	panic("Atomic not supported");
	}

	Tick
	MemCheckerMonitor::recvAtomicSnoop(PacketPtr pkt)
	{
	panic("Atomic not supported");
	}

	bool
	MemCheckerMonitor::recvTimingReq(PacketPtr pkt)
	{
	// should always see a request
	assert(pkt->isRequest());

	// Store relevant fields of packet, because packet may be modified
	// or even deleted when sendTiming() is called.
	//
	// For reads we are only interested in real reads, and not prefetches, as
	// it is not guaranteed that the prefetch returns any useful data.
	bool is_read = pkt->isRead() && !pkt->req->isPrefetch();
	bool is_write = pkt->isWrite();
	unsigned size = pkt->getSize();
	Addr addr = pkt->getAddr();
	bool expects_response = pkt->needsResponse() && !pkt->cacheResponding();
	std::unique_ptr<uint8_t[]> pkt_data;
	MemCheckerMonitorSenderState* state = NULL;

	if (expects_response && is_write) {
	// On receipt of a request, only need to allocate pkt_data if this is a
	// write. For reads, we have no data yet, so it doesn't make sense to
	// allocate.
	pkt_data.reset(new uint8_t[size]);
	pkt->writeData(pkt_data.get());
	}

	// If a cache miss is served by a cache, a monitor near the memory
	// would see a request which needs a response, but this response
	// would not come back from the memory. Therefore
	// we additionally have to check the inhibit flag.
	if (expects_response && (is_read \|\| is_write)) {
	state = new MemCheckerMonitorSenderState(0);
	pkt->pushSenderState(state);
	}

	// Attempt to send the packet
	bool successful = masterPort.sendTimingReq(pkt);

	// If not successful, restore the sender state
	if (!successful && expects_response && (is_read \|\| is_write)) {
	delete pkt->popSenderState();
	}

	if (successful && expects_response) {
	if (is_read) {
	MemChecker::Serial serial = memchecker->startRead(curTick(),
	addr,
	size);

	// At the time where we push the sender-state, we do not yet know
	// the serial the MemChecker class will assign to this request. We
	// cannot call startRead at the time we push the sender-state, as
	// the masterPort may not be successful in executing sendTimingReq,
	// and in case of a failure, we must not modify the state of the
	// MemChecker.
	//
	// Once we know that sendTimingReq was successful, we can set the
	// serial of the newly constructed sender-state. This is legal, as
	// we know that nobody else will touch nor is responsible for
	// deletion of our sender-state.
	state->serial = serial;

	DPRINTF(MemCheckerMonitor,
	"Forwarded read request: serial = %d, addr = %#llx, "
	"size = %d\n",
	serial, addr, size);
	} else if (is_write) {
	MemChecker::Serial serial = memchecker->startWrite(curTick(),
	addr,
	size,
	pkt_data.get());

	state->serial = serial;

	DPRINTF(MemCheckerMonitor,
	"Forwarded write request: serial = %d, addr = %#llx, "
	"size = %d\n",
	serial, addr, size);
	} else {
	DPRINTF(MemCheckerMonitor,
	"Forwarded non read/write request: addr = %#llx\n", addr);
	}
	} else if (successful) {
	DPRINTF(MemCheckerMonitor,
	"Forwarded request marked for cache response: addr = %#llx\n",
	addr);
	}

	return successful;
	}

	bool
	MemCheckerMonitor::recvTimingResp(PacketPtr pkt)
	{
	// should always see responses
	assert(pkt->isResponse());

	// Store relevant fields of packet, because packet may be modified
	// or even deleted when sendTiming() is called.
	bool is_read = pkt->isRead() && !pkt->req->isPrefetch();
	bool is_write = pkt->isWrite();
	bool is_failed_LLSC = pkt->isLLSC() && pkt->req->getExtraData() == 0;
	unsigned size = pkt->getSize();
	Addr addr = pkt->getAddr();
	std::unique_ptr<uint8_t[]> pkt_data;
	MemCheckerMonitorSenderState* received_state = NULL;

	if (is_read) {
	// On receipt of a response, only need to allocate pkt_data if this is
	// a read. For writes, we have already given the MemChecker the data on
	// the request, so it doesn't make sense to allocate on write.
	pkt_data.reset(new uint8_t[size]);
	pkt->writeData(pkt_data.get());
	}

	if (is_read \|\| is_write) {
	received_state =
	dynamic_cast<MemCheckerMonitorSenderState*>(pkt->senderState);

	// Restore initial sender state
	panic_if(received_state == NULL,
	"Monitor got a response without monitor sender state\n");

	// Restore the state
	pkt->senderState = received_state->predecessor;
	}

	// Attempt to send the packet
	bool successful = slavePort.sendTimingResp(pkt);

	// If packet successfully send, complete transaction in MemChecker
	// instance, and delete sender state, otherwise restore state.
	if (successful) {
	if (is_read) {
	DPRINTF(MemCheckerMonitor,
	"Received read response: serial = %d, addr = %#llx, "
	"size = %d\n",
	received_state->serial, addr, size);

	bool result = memchecker->completeRead(received_state->serial,
	curTick(),
	addr,
	size,
	pkt_data.get());

	if (!result) {
	warn("%s: read of %#llx @ cycle %d failed:\n%s\n",
	name(),
	addr, curTick(),
	memchecker->getErrorMessage().c_str());

	panic_if(!warnOnly, "MemChecker violation!");
	}

	delete received_state;
	} else if (is_write) {
	DPRINTF(MemCheckerMonitor,
	"Received write response: serial = %d, addr = %#llx, "
	"size = %d\n",
	received_state->serial, addr, size);

	if (is_failed_LLSC) {
	// The write was not successful, let MemChecker know.
	memchecker->abortWrite(received_state->serial,
	addr,
	size);
	} else {
	memchecker->completeWrite(received_state->serial,
	curTick(),
	addr,
	size);
	}

	delete received_state;
	} else {
	DPRINTF(MemCheckerMonitor,
	"Received non read/write response: addr = %#llx\n", addr);
	}
	} else if (is_read \|\| is_write) {
	// Don't delete anything and let the packet look like we
	// did not touch it
	pkt->senderState = received_state;
	}

	return successful;
	}

	void
	MemCheckerMonitor::recvTimingSnoopReq(PacketPtr pkt)
	{
	slavePort.sendTimingSnoopReq(pkt);
	}

	bool
	MemCheckerMonitor::recvTimingSnoopResp(PacketPtr pkt)
	{
	return masterPort.sendTimingSnoopResp(pkt);
	}

	bool
	MemCheckerMonitor::isSnooping() const
	{
	// check if the connected master port is snooping
	return slavePort.isSnooping();
	}

	AddrRangeList
	MemCheckerMonitor::getAddrRanges() const
	{
	// get the address ranges of the connected slave port
	return masterPort.getAddrRanges();
	}

	void
	MemCheckerMonitor::recvReqRetry()
	{
	slavePort.sendRetryReq();
	}

	void
	MemCheckerMonitor::recvRespRetry()
	{
	masterPort.sendRetryResp();
	}

	void
	MemCheckerMonitor::recvRangeChange()
	{
	slavePort.sendRangeChange();
	}