Make sure we only pick up GRAALPY_HOME for a custom benchmark config

Author: timfel

mx.graalpython/mx_graalpython.py

@@ -321,7 +321,7 @@ def graalpy_native_pgo_build_and_test(_):
                 GRAALPY_HOME=instrumented_home,
         ):
             graalpytest(["--python", instrumented_launcher, "test_venv.py"])
-            mx.command_function('benchmark')(["meso-small:*"])
+            mx.command_function('benchmark')(["meso-small:*", "--", "--python-vm", "graalpython", "--python-vm-config", "custom"])
 
         iprof_path = Path(SUITE.dir) / 'default.iprof'
         lcov_path = Path(SUITE.dir) / 'default.lcov'

mx.graalpython/mx_graalpython_benchmark.py

@@ -62,6 +62,7 @@
 
 PYTHON_VM_REGISTRY_NAME = "Python"
 CONFIGURATION_DEFAULT = "default"
+CONFIGURATION_CUSTOM = "custom"
 CONFIGURATION_INTERPRETER = "interpreter"
 CONFIGURATION_NATIVE_INTERPRETER = "native-interpreter"
 CONFIGURATION_DEFAULT_MULTI = "default-multi"
@@ -279,9 +280,12 @@ def launcher_type(self):
     @property
     @functools.lru_cache
     def interpreter(self):
-        if home := mx.get_env("GRAALPY_HOME"):
+        if self.config_name() == CONFIGURATION_CUSTOM:
+            home = mx.get_env("GRAALPY_HOME")
+            if not home:
+                mx.abort("The custom benchmark config for graalpy is to run with a custom GRAALPY_HOME locally")
             launcher = join(home, "bin", "graalpy")
-            mx.log(f"Using {launcher} based on GRAALPY_HOME environment variable.")
+            mx.log(f"Using {launcher} based on GRAALPY_HOME environment for custom config.")
             return launcher
         from mx_graalpython import graalpy_standalone
         launcher = graalpy_standalone(self.launcher_type, build=False)
@@ -1033,6 +1037,7 @@ def add_graalpy_vm(name, *extra_polyglot_args):
         python_vm_registry.add_vm(GraalPythonVm(config_name=name, extra_polyglot_args=extra_polyglot_args), suite, 10)
 
     # GraalPy VMs:
+    add_graalpy_vm(CONFIGURATION_CUSTOM)
     add_graalpy_vm(CONFIGURATION_DEFAULT)
     add_graalpy_vm(CONFIGURATION_INTERPRETER, '--experimental-options', '--engine.Compilation=false')
     add_graalpy_vm(CONFIGURATION_DEFAULT_MULTI, '--experimental-options', '-multi-context')