Add support for disabling turbo boost on more CPUs

docs/denoise.md

@@ -5,7 +5,7 @@ It adjusts the system settings to reduce interference by:
 
  - raising the process priority to minimize the impact of the process scheduler 
  - using CPU core shielding to minimize interference from other processes
- - requesting the system to avoid tubo-boosting to keep the CPU at a constant frequency
+ - requesting the system to avoid turbo-boosting to keep the CPU at a constant frequency
  - requesting the system to use a performance governor, which tries to keep the CPU at a high frequency
  - reducing the frequency with which perf events can be collected, except when in profiling mode
 

rebench/denoise.py

@@ -4,20 +4,29 @@
 import sys
 
 from argparse import ArgumentParser
+from glob import glob
 from math import log, floor
 from multiprocessing import Pool
+from os.path import isfile, join as path_join, abspath, dirname, realpath
 from subprocess import check_output, CalledProcessError, DEVNULL, STDOUT
-from typing import Optional, Union, Literal, TypedDict, TYPE_CHECKING
+from typing import (
+    Literal,
+    Optional,
+    Tuple,
+    TypedDict,
+    Union,
+    TYPE_CHECKING,
+)
 
 if TYPE_CHECKING:
     from typing import NotRequired
 
-denoise_py = os.path.abspath(__file__)
+denoise_py = abspath(__file__)
 
 if __name__ == "__main__":
     # ensure that the rebench module is available
-    rebench_module = os.path.dirname(denoise_py)
-    sys.path.append(os.path.dirname(rebench_module))
+    rebench_module = dirname(denoise_py)
+    sys.path.append(dirname(rebench_module))
 
     # pylint: disable-next=import-error
     from output import output_as_str, UIError  # type: ignore
@@ -65,7 +74,7 @@ def __init__(self):
 
     def get_which(self):
         if not self._which_path:
-            if os.path.isfile("/usr/bin/which"):
+            if isfile("/usr/bin/which"):
                 self._which_path = "/usr/bin/which"
             else:
                 raise UIError(
@@ -87,7 +96,7 @@ def absolute_path_for_command(self, command, arguments_for_successful_exe):
             selected_cmd = output_as_str(
                 check_output([self.get_which(), command], shell=False, stderr=DEVNULL)
             ).strip()
-            result_cmd = os.path.realpath(selected_cmd)
+            result_cmd = realpath(selected_cmd)
         except CalledProcessError:
             result_cmd = command
 
@@ -115,7 +124,7 @@ def ensure_denoise(self):
         if self._denoise_path is None:
             if os.access(denoise_py, os.X_OK):
                 self._denoise_path = denoise_py
-            elif not os.path.isfile(denoise_py):
+            elif not isfile(denoise_py):
                 raise UIError(
                     f"{denoise_py} not found. "
                     "Could it be that the user has no access to the file? "
@@ -269,32 +278,73 @@ def _set_scaling_governor(governor, num_cores) -> str:
     return governor
 
 
+_INTEL_NO_TURBO = "/sys/devices/system/cpu/intel_pstate/no_turbo"
+_CPUFREQ_BOOST = "/sys/devices/system/cpu/cpufreq/boost"
+_CPUFREQ_POLICY_DIR = "/sys/devices/system/cpu/cpufreq"
+
+
+def _find_turbo_boost_control() -> Union[Tuple[list[str], bool], str]:
+    """
+    Find the paths that allow us to disable turbo boost.
+    """
+    if isfile(_INTEL_NO_TURBO):
+        return [_INTEL_NO_TURBO], True
+
+    if isfile(_CPUFREQ_BOOST):
+        return [_CPUFREQ_BOOST], False
+
+    # e.g. amd-pstate in active mode only provides per-policy boost files
+    policy_boost_files = sorted(
+        glob(path_join(_CPUFREQ_POLICY_DIR, "policy*", "boost"))
+    )
+    if policy_boost_files:
+        return policy_boost_files, False
+
+    return (
+        "failed: No turbo boost control found. Checked "
+        + _INTEL_NO_TURBO
+        + ", "
+        + _CPUFREQ_BOOST
+        + ", and "
+        + path_join(_CPUFREQ_POLICY_DIR, "policy*", "boost")
+    )
+
+
 def _read_no_turbo() -> Optional[Union[bool, str]]:
+    control = _find_turbo_boost_control()
+    if isinstance(control, str):
+        return control
+
+    files, indicates_disabled = control
     try:
-        with open(
-            "/sys/devices/system/cpu/intel_pstate/no_turbo", "r", encoding="utf-8"
-        ) as nt_file:
-            return nt_file.read().strip() == "1"
+        values = []
+        for filename in files:
+            with open(filename, "r", encoding="utf-8") as nt_file:
+                values.append(nt_file.read().strip() == "1")
     except IOError as e:
-        if e.errno == 2 and "No such file" in str(e):
-            return "failed: No such file: /sys/devices/system/cpu/intel_pstate/no_turbo"
         return "failed: " + str(e)
 
+    if indicates_disabled:
+        return all(values)
+    return not any(values)
+
 
 def _set_no_turbo(no_turbo_value: bool) -> Union[Literal[True], str]:
-    if no_turbo_value:
-        value = "1"
+    control = _find_turbo_boost_control()
+    if isinstance(control, str):
+        return control
+
+    files, indicates_disabled = control
+    if indicates_disabled:
+        value = "1" if no_turbo_value else "0"
     else:
-        value = "0"
+        value = "0" if no_turbo_value else "1"
 
     try:
-        with open(
-            "/sys/devices/system/cpu/intel_pstate/no_turbo", "w", encoding="utf-8"
-        ) as nt_file:
-            nt_file.write(value + "\n")
+        for filename in files:
+            with open(filename, "w", encoding="utf-8") as nt_file:
+                nt_file.write(value + "\n")
     except IOError as e:
-        if e.errno == 2 and "No such file" in str(e):
-            return "failed: No such file: /sys/devices/system/cpu/intel_pstate/no_turbo"
         return "failed: " + str(e)
 
     return True

rebench/tests/integration_test.py

@@ -65,9 +65,24 @@ def test_rebench(rebench_cmd, rebench_conf, rebench_module_path, test_data_file)
         "can_set_scaling_governor",
         "can_minimize_perf_sampling",
     ],
-    "cassius": ["can_set_nice", "can_set_scaling_governor"],
-    "laertes": ["can_set_nice", "can_set_scaling_governor"],
-    "ophelia": ["can_set_nice", "can_set_scaling_governor"],
+    "cassius": [
+        "can_set_nice",
+        "can_set_scaling_governor",
+        "initial_no_turbo",
+        "can_minimize_perf_sampling",
+    ],
+    "laertes": [
+        "can_set_nice",
+        "can_set_scaling_governor",
+        "initial_no_turbo",
+        "can_minimize_perf_sampling",
+    ],
+    "ophelia": [
+        "can_set_nice",
+        "can_set_scaling_governor",
+        "initial_no_turbo",
+        "can_minimize_perf_sampling",
+    ],
     "zullie1": ["can_set_nice"],
 }
 _default_capabilities = [
@@ -111,11 +126,21 @@ def test_machine_denoise_capabilities():
         assert isinstance(
             capabilities, dict
         ), f"Expected capabilities to be a dict, but got {capabilities}"
+
+        bool_expectations = {}
+        for k, v in capabilities.items():
+            if v is True:
+                bool_expectations[k] = v
+
         for cap in expectations:
-            assert cap in capabilities, (
+            assert cap in bool_expectations, (
                 f"Expected {cap} to be in capabilities, but got {capabilities},"
                 f" got_json: {got_json}, raw_output: {raw_output} on {hostname}"
             )
             assert (
-                capabilities[cap] is True
+                bool_expectations[cap] is True
             ), f"Expected {cap} to be True, but got {capabilities} on {hostname}"
+            del bool_expectations[cap]
+        assert (
+            not bool_expectations
+        ), f"Expected no more capabilities, but got {bool_expectations}"