def test_cpu_freq_procfs(tmp_path: pathlib.Path) -> None:
populate_directory(
str(tmp_path),
{
"sysfs": {
"devices": {
"system": {
"cpu": {}
}
}
},
"procfs": {
"cpuinfo":
"""
core id: 0
physical id: 0
cpu MHz: 2000
core id: 1
physical id: 0
cpu MHz: 2500
"""
},
},
)
with replace_info_directories(sysfs=str(tmp_path / "sysfs"),
procfs=str(tmp_path / "procfs")):
assert pypsutil.percpu_freq() == [ # type: ignore
pypsutil.CPUFrequencies(current=2000, min=0, max=0),
pypsutil.CPUFrequencies(current=2500, min=0, max=0),
]
assert pypsutil.cpu_freq() == ( # type: ignore
pypsutil.CPUFrequencies(current=2250, min=0, max=0))
def test_cpu_freq_range() -> None:
freqs = pypsutil.cpu_freq() # type: ignore[attr-defined] # pylint: disable=no-member
if freqs is None:
pytest.skip("Unable to determine CPU frequencies")
assert freqs.current > 0
assert freqs.min == 0.0 or freqs.current >= freqs.min
assert freqs.max == 0.0 or freqs.current <= freqs.max
def test_cpu_freq_none(tmp_path: pathlib.Path) -> None:
populate_directory(
str(tmp_path),
{
"sysfs": {},
"procfs": {}
},
)
with replace_info_directories(sysfs=str(tmp_path / "sysfs"),
procfs=str(tmp_path / "procfs")):
assert pypsutil.percpu_freq() == [] # type: ignore
assert pypsutil.cpu_freq() is None # type: ignore
def test_cpu_freq_sysfs(tmp_path: pathlib.Path) -> None:
populate_directory(
str(tmp_path),
{
"devices": {
"system": {
"cpu": {
"cpu0": {
"cpufreq": {
"scaling_min_freq": "1000000",
"scaling_cur_freq": "2000000",
"scaling_max_freq": "3000000",
},
},
"cpu1": {
"cpufreq": {
"scaling_min_freq": "1500000",
"scaling_cur_freq": "2500000",
"scaling_max_freq": "3500000",
},
},
"online": "0-4",
}
}
}
},
)
with replace_info_directories(sysfs=str(tmp_path)):
assert pypsutil.percpu_freq() == [ # type: ignore
pypsutil.CPUFrequencies(current=2000, min=1000, max=3000),
pypsutil.CPUFrequencies(current=2500, min=1500, max=3500),
]
assert pypsutil.cpu_freq() == ( # type: ignore
pypsutil.CPUFrequencies(current=2250, min=1250, max=3250))
def cpu_freq(
percpu: bool = False,
) -> Union[pypsutil.CPUFrequencies, List[pypsutil.CPUFrequencies]]:
return pypsutil.percpu_freq() if percpu else pypsutil.cpu_freq() # type: ignore
time.sleep(3)
message_bit = []
"""
The transmit unit is pretty easy to understand. However, here needs more explanation.
We monitor the CPU frequency 9-10 time in each 5-second interval and add the signals to frequency list.
At the end of 5 seconds, we calculate of average of the frequency list to make sure the signal is 1 or 0.
Feel free the to modify the timing and let me know if you find a better tweak.
Note: in the tested device, CPU frequency is 2800Mhz under load and 1000 when ideal. So, I chose a threshold of 2000.
"""
busy_threshold = 2000
number_of_bits = 80
for i in range(number_of_bits):
frequency = []
start = int(time.time())
while int(time.time()) - start < 5:
if pypsutil.cpu_freq().current > busy_threshold:
frequency.append(1)
else:
frequency.append(0)
time.sleep(0.5)
signal = sum(frequency) / len(frequency)
if signal > 0.5:
message_bit.append(1)
else:
message_bit.append(0)
print(message_bit)
print(message_bit)
message_bit = ''.join(str(x) for x in message_bit)
"""
We added { to the beginning of the message and } to the end of it.