stdlib,tests: Fix stdlib SE mode for multicore setups

The `set_se_binary_workload` function was only setting up the binary to
work on one (the first) processor core. This caused an exception to be
thrown when trying to run an SE mode binary on a multicore system.

Tests have been added to ensure this works as intended.

Note: While this implementation fixes the bugs, it is limited. Future
work is needed to allow for multiprogram workloads.

Change-Id: I33dbaf5015705c299215dc83e8449b16df301cd4
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/62014
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>

src/python/gem5/components/boards/se_binary_workload.py

@@ -40,6 +40,10 @@ class SEBinaryWorkload:
     For this to function correctly the SEBinaryWorkload class should be added
     as a superclass to a board (i.e., something that inherits from
     AbstractBoard).
+
+    **Important Notes:** At present this implementation is limited. A single
+    process is added to all cores as the workload. Therefore, despite allowing
+    for multi-core setups, multi-program workloads are not presently supported.
     """
 
     def set_se_binary_workload(
@@ -52,7 +56,7 @@ class SEBinaryWorkload:
         """Set up the system to run a specific binary.
 
         **Limitations**
-        * Only supports single threaded applications
+        * Only supports single threaded applications.
         * Dynamically linked executables are partially supported when the host
           ISA and the simulated ISA are the same.
 
@@ -80,7 +84,8 @@ class SEBinaryWorkload:
         if stdin_file is not None:
             process.input = stdin_file.get_local_path()
 
-        self.get_processor().get_cores()[0].set_workload(process)
+        for core in self.get_processor().get_cores():
+            core.set_workload(process)
 
         # Set whether to exit on work items for the se_workload
         self.exit_on_work_items = exit_on_work_items

tests/gem5/configs/simple_binary_run.py

@@ -90,6 +90,15 @@ parser.add_argument(
     help="The input arguments for the binary.",
 )
 
+parser.add_argument(
+    "-n",
+    "--num-cores",
+    type=int,
+    default=1,
+    required=False,
+    help="The number of CPU cores to run.",
+)
+
 args = parser.parse_args()
 
 # Setup the system.
@@ -102,10 +111,11 @@ if args.base_cpu_processor:
             core=SimpleCore.cpu_simobject_factory(
                 cpu_type=get_cpu_type_from_str(args.cpu),
                 isa=get_isa_from_str(args.isa),
-                core_id=0,
+                core_id=i,
             ),
             isa=get_isa_from_str(args.isa),
         )
+        for i in range(args.num_cores)
     ]
 
     processor = BaseCPUProcessor(
@@ -115,7 +125,7 @@ else:
     processor = SimpleProcessor(
         cpu_type=get_cpu_type_from_str(args.cpu),
         isa=get_isa_from_str(args.isa),
-        num_cores=1,
+        num_cores=args.num_cores,
     )
 
 motherboard = SimpleBoard(

tests/gem5/se_mode/hello_se/test_se_multicore.py

@@ -0,0 +1,56 @@
+# Copyright (c) 2022 The Regents of the University of California
+# All Rights Reserved.
+#
+# 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.
+
+"""
+Tests which test SE mode's functionality when running workloads on multiple
+core setups.
+"""
+from testlib import *
+
+if config.bin_path:
+    resource_path = config.bin_path
+else:
+    resource_path = joinpath(absdirpath(__file__), "..", "..", "resources")
+
+gem5_verify_config(
+    name="test-x86-hello-4-atomic-core-se-mode",
+    fixtures=(),
+    verifiers=(),
+    config=joinpath(
+        config.base_dir, "tests", "gem5", "configs", "simple_binary_run.py"
+    ),
+    config_args=[
+        "x86-hello64-static",
+        "atomic",
+        "x86",
+        "--num-cores",
+        "4",
+        "--resource-directory",
+        resource_path,
+    ],
+    valid_isas=(constants.vega_x86_tag,),
+    length=constants.quick_tag,
+)