Add CPU frequency support for FreeBSD (#1369)

Add CPU frequency support for FreeBSD (patch by @amanusk)

psutil/_psbsd.py

@@ -455,6 +455,32 @@ def sensors_temperatures():
 
         return ret
 
+    def cpu_freq():
+        """
+        Return frequency metrics for CPUs. Currently, only CPU 0 is supported
+        by FreeBSD, all other cores match the frequency of CPU 0.
+        """
+        ret = []
+        num_cpus = cpu_count_logical()
+        for cpu in range(num_cpus):
+            try:
+                current, available_freq = cext.cpu_frequency(cpu)
+            except NotImplementedError:
+                continue
+            min_freq = None
+            max_freq = None
+            if available_freq:
+                try:
+                    min_freq = int(available_freq.split(" ")[-1].split("/")[0])
+                except(IndexError, ValueError):
+                    pass
+                try:
+                    max_freq = int(available_freq.split(" ")[0].split("/")[0])
+                except(IndexError, ValueError):
+                    pass
+            ret.append(_common.scpufreq(current, min_freq, max_freq))
+        return ret
+
 
 # =====================================================================
 #  --- other system functions

psutil/_psutil_bsd.c

@@ -983,6 +983,8 @@ PsutilMethods[] = {
      "Return battery information."},
     {"sensors_cpu_temperature", psutil_sensors_cpu_temperature, METH_VARARGS,
      "Return temperature information for a given CPU core number."},
+    {"cpu_frequency", psutil_cpu_freq, METH_VARARGS,
+     "Return frequency of a given CPU"},
 #endif
 
     // --- others

psutil/arch/freebsd/specific.c

@@ -1046,3 +1046,36 @@ psutil_sensors_cpu_temperature(PyObject *self, PyObject *args) {
         PyErr_SetFromErrno(PyExc_OSError);
     return NULL;
 }
+
+
+/*
+ * Return frequency information of a given CPU
+ */
+PyObject *
+psutil_cpu_freq(PyObject *self, PyObject *args) {
+    int current;
+    int core;
+    char sensor[26];
+    char available_freq_levels[1000];
+    size_t size = sizeof(current);
+
+    if (! PyArg_ParseTuple(args, "i", &core))
+        return NULL;
+    sprintf(sensor, "dev.cpu.%d.freq", core);
+    if (sysctlbyname(sensor, &current, &size, NULL, 0))
+        goto error;
+
+    size = sizeof(available_freq_levels);
+    // In case of failure, an empty string is returned
+    sprintf(sensor, "dev.cpu.%d.freq_levels", core);
+    sysctlbyname(sensor, &available_freq_levels, &size, NULL, 0);
+
+    return Py_BuildValue("is", current, available_freq_levels);
+
+error:
+    if (errno == ENOENT)
+        PyErr_SetString(PyExc_NotImplementedError, "Unable to read frequency");
+    else
+        PyErr_SetFromErrno(PyExc_OSError);
+    return NULL;
+}

psutil/arch/freebsd/specific.h

@@ -30,4 +30,5 @@ PyObject* psutil_cpu_stats(PyObject* self, PyObject* args);
 #if defined(PSUTIL_FREEBSD)
 PyObject* psutil_sensors_battery(PyObject* self, PyObject* args);
 PyObject* psutil_sensors_cpu_temperature(PyObject* self, PyObject* args);
+PyObject* psutil_cpu_freq(PyObject* self, PyObject* args);
 #endif

psutil/tests/test_bsd.py

@@ -250,6 +250,24 @@ def test_proc_cpu_times(self):
         if len(tested) != 2:
             raise RuntimeError("couldn't find lines match in procstat out")
 
+    # --- cpu_freq(); tests against sysctl
+    def test_cpu_frequency_against_sysctl(self):
+        # Currently only cpu 0 is frequency is supported in FreeBSD
+        # All other cores use the same frequency
+        sensor = "dev.cpu.0.freq"
+        sysctl_result = int(sysctl(sensor))
+        self.assertEqual(psutil.cpu_freq().current, sysctl_result)
+
+        sensor = "dev.cpu.0.freq_levels"
+        sysctl_result = sysctl(sensor)
+        # sysctl returns a string of the format:
+        # <freq_level_1>/<voltage_level_1> <freq_level_2>/<voltage_level_2>...
+        # Ordered highest available to lowest available
+        max_freq = int(sysctl_result.split()[0].split("/")[0])
+        min_freq = int(sysctl_result.split()[-1].split("/")[0])
+        self.assertEqual(psutil.cpu_freq().max, max_freq)
+        self.assertEqual(psutil.cpu_freq().min, min_freq)
+
     # --- virtual_memory(); tests against sysctl
 
     @retry_before_failing()

psutil/tests/test_contracts.py

@@ -115,7 +115,7 @@ def test_cpu_freq(self):
                  (os.path.exists("/sys/devices/system/cpu/cpufreq") or
                   os.path.exists("/sys/devices/system/cpu/cpu0/cpufreq")))
         self.assertEqual(hasattr(psutil, "cpu_freq"),
-                         linux or MACOS or WINDOWS)
+                         linux or MACOS or WINDOWS or FREEBSD)
 
     def test_sensors_temperatures(self):
         self.assertEqual(