cpu: Get rid of load count based events.

This was initially added in 2003 and only supported in the simple CPUs.
It's oddly specific since there are no other similar event queues for,
for instance, stores, branches, system calls, etc.

Given that this seems like a historical oddity which is only partially
supported and would be very hard to support on more diverse CPU types
like KVM or fast model which don't generally have hooks for counts of
specific instruction types.

Change-Id: I29209b7ffcf896cf424b71545c9c7546f439e2b9
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/21780
Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

diff --git a/src/cpu/BaseCPU.py b/src/cpu/BaseCPU.py
index 0e8c28917753781ae69fa2079ad5187ce7d181ca..85e37776e8e4f619aff0ac12a51783ad79479f86 100644 (file)
--- a/src/cpu/BaseCPU.py
+++ b/src/cpu/BaseCPU.py
@@ -122,7 +122,6 @@ class BaseCPU(ClockedObject):
         PyBindMethod("flushTLBs"),
         PyBindMethod("totalInsts"),
         PyBindMethod("scheduleInstStop"),
-        PyBindMethod("scheduleLoadStop"),
         PyBindMethod("getCurrentInstCount"),
     ]
 
@@ -196,10 +195,6 @@ class BaseCPU(ClockedObject):
         "terminate when any thread reaches this inst count")
     simpoint_start_insts = VectorParam.Counter([],
         "starting instruction counts of simpoints")
-    max_loads_all_threads = Param.Counter(0,
-        "terminate when all threads have reached this load count")
-    max_loads_any_thread = Param.Counter(0,
-        "terminate when any thread reaches this load count")
     progress_interval = Param.Frequency('0Hz',
         "frequency to print out the progress message")
 

diff --git a/src/cpu/base.cc b/src/cpu/base.cc
index 5bc3fe7c75b21d3322ffd0b26c4d835fd0418b73..7e0e79e9635dfd3ea7120aded3c0c226e752bad9 100644 (file)
--- a/src/cpu/base.cc
+++ b/src/cpu/base.cc
@@ -195,32 +195,9 @@ BaseCPU::BaseCPU(Params *p, bool is_checker)
         }
     }
 
-    // allocate per-thread load-based event queues
-    comLoadEventQueue = new EventQueue *[numThreads];
-    for (ThreadID tid = 0; tid < numThreads; ++tid)
-        comLoadEventQueue[tid] = new EventQueue("load-based event queue");
-
     //
     // set up instruction-count-based termination events, if any
     //
-    if (p->max_loads_any_thread != 0) {
-        const char *cause = "a thread reached the max load count";
-        for (ThreadID tid = 0; tid < numThreads; ++tid)
-            scheduleLoadStop(tid, p->max_loads_any_thread, cause);
-    }
-
-    if (p->max_loads_all_threads != 0) {
-        const char *cause = "all threads reached the max load count";
-        // allocate & initialize shared downcounter: each event will
-        // decrement this when triggered; simulation will terminate
-        // when counter reaches 0
-        int *counter = new int;
-        *counter = numThreads;
-        for (ThreadID tid = 0; tid < numThreads; ++tid) {
-            Event *event = new CountedExitEvent(cause, *counter);
-            comLoadEventQueue[tid]->schedule(event, p->max_loads_all_threads);
-        }
-    }
 
     functionTracingEnabled = false;
     if (p->function_trace) {
@@ -273,7 +250,6 @@ BaseCPU::enableFunctionTrace()
 BaseCPU::~BaseCPU()
 {
     delete profileEvent;
-    delete[] comLoadEventQueue;
     delete[] comInstEventQueue;
 }
 
@@ -781,15 +757,6 @@ bool AddressMonitor::doMonitor(PacketPtr pkt) {
     return false;
 }
 
-void
-BaseCPU::scheduleLoadStop(ThreadID tid, Counter loads, const char *cause)
-{
-    const Tick now(comLoadEventQueue[tid]->getCurTick());
-    Event *event(new LocalSimLoopExitEvent(cause, 0));
-
-    comLoadEventQueue[tid]->schedule(event, now + loads);
-}
-
 
 void
 BaseCPU::traceFunctionsInternal(Addr pc)

diff --git a/src/cpu/base.hh b/src/cpu/base.hh
index dfee21fabf8504474759cfe7f60337b9ca1cbe34..383ae818528d26f6aad05c30fe8417f26e473d80 100644 (file)
--- a/src/cpu/base.hh
+++ b/src/cpu/base.hh
@@ -390,13 +390,6 @@ class BaseCPU : public ClockedObject
      */
     EventQueue **comInstEventQueue;
 
-    /**
-     * Vector of per-thread load-based event queues.  Used for
-     * scheduling events based on number of loads committed by
-     *a particular thread.
-     */
-    EventQueue **comLoadEventQueue;
-
     System *system;
 
     /**
@@ -463,21 +456,6 @@ class BaseCPU : public ClockedObject
      */
     void scheduleInstStop(ThreadID tid, Counter insts, const char *cause);
 
-    /**
-     * Schedule an event that exits the simulation loops after a
-     * predefined number of load operations.
-     *
-     * This method is usually called from the configuration script to
-     * get an exit event some time in the future. It is typically used
-     * when the script wants to simulate for a specific number of
-     * loads rather than ticks.
-     *
-     * @param tid Thread monitor.
-     * @param loads Number of load instructions into the future.
-     * @param cause Cause to signal in the exit event.
-     */
-    void scheduleLoadStop(ThreadID tid, Counter loads, const char *cause);
-
     /**
      * Get the number of instructions executed by the specified thread
      * on this CPU. Used by Python to control simulation.

diff --git a/src/cpu/dummy_checker.cc b/src/cpu/dummy_checker.cc
index c42c8b5d604a7b5e7abe5f2e636086d83c3915b8..d119d618967f169109c475467d9c29e88f5f051a 100644 (file)
--- a/src/cpu/dummy_checker.cc
+++ b/src/cpu/dummy_checker.cc
@@ -48,7 +48,6 @@ DummyCheckerParams::create()
     // cpu and therefore any parameters for early exit don't make much
     // sense.
     fatal_if(max_insts_any_thread || max_insts_all_threads ||
-             max_loads_any_thread || max_loads_all_threads ||
              progress_interval, "Invalid checker parameters");
 
     return new DummyChecker(this);

diff --git a/src/cpu/o3/checker.cc b/src/cpu/o3/checker.cc
index 1713da7c1365bb3f6bdff1aad27875a9a5572c11..fdf7ec654e230a46fc36942a15ac5b345b7f9fd3 100644 (file)
--- a/src/cpu/o3/checker.cc
+++ b/src/cpu/o3/checker.cc
@@ -55,7 +55,6 @@ O3CheckerParams::create()
     // cpu and therefore any parameters for early exit don't make much
     // sense.
     fatal_if(max_insts_any_thread || max_insts_all_threads ||
-             max_loads_any_thread || max_loads_all_threads ||
              progress_interval, "Invalid checker parameters");
 
     return new O3Checker(this);

diff --git a/src/cpu/simple/base.cc b/src/cpu/simple/base.cc
index b93ae091281d6763b34cd50f4b2c3805640f059f..461f00fca3e870a80e03b44ab5df2d87bdd7d811 100644 (file)
--- a/src/cpu/simple/base.cc
+++ b/src/cpu/simple/base.cc
@@ -600,7 +600,6 @@ BaseSimpleCPU::postExecute()
 
     if (curStaticInst->isLoad()) {
         ++t_info.numLoad;
-        comLoadEventQueue[curThread]->serviceEvents(t_info.numLoad);
     }
 
     if (CPA::available()) {