#[macro_use]
extern crate smart_default;
use std::io::{self, Read, Write};
use std::fmt::Display;
use std::fs::{File, OpenOptions};
use std::path::{Path, PathBuf};
use std::str::FromStr;
#[derive(Copy, Clone, Debug, Eq, Hash, PartialEq, SmartDefault)]
pub struct PStateValues {
pub min_perf_pct: u8,
#[default = "100"]
pub max_perf_pct: u8,
pub no_turbo: bool
}
pub struct PState {
path: PathBuf,
}
impl PState {
pub fn new() -> io::Result<PState> {
let path = PathBuf::from("/sys/devices/system/cpu/intel_pstate");
if path.is_dir() {
Ok(PState { path })
} else {
Err(io::Error::new(io::ErrorKind::NotFound, "intel_pstate directory not found"))
}
}
pub fn min_perf_pct(&self) -> io::Result<u8> {
parse_file(self.path.join("min_perf_pct"))
}
pub fn set_min_perf_pct(&self, value: u8) -> io::Result<()> {
write_file(self.path.join("min_perf_pct"), format!("{}", value))
}
pub fn max_perf_pct(&self) -> io::Result<u8> {
parse_file(self.path.join("max_perf_pct"))
}
pub fn set_max_perf_pct(&self, value: u8) -> io::Result<()> {
write_file(self.path.join("max_perf_pct"), format!("{}", value))
}
pub fn no_turbo(&self) -> io::Result<bool> {
let value: u8 = parse_file(self.path.join("no_turbo"))?;
Ok(value > 0)
}
pub fn set_no_turbo(&self, value: bool) -> io::Result<()> {
write_file(self.path.join("no_turbo"), if value { "1" } else { "0" })
}
pub fn values(&self) -> io::Result<PStateValues> {
let values = PStateValues {
min_perf_pct: self.min_perf_pct()?,
max_perf_pct: self.max_perf_pct()?,
no_turbo: self.no_turbo()?
};
Ok(values)
}
pub fn set_values(&self, values: PStateValues) -> io::Result<()> {
self.set_min_perf_pct(values.min_perf_pct)?;
self.set_max_perf_pct(values.max_perf_pct)?;
self.set_no_turbo(values.no_turbo)
}
}
fn read_file<P: AsRef<Path>>(path: P) -> io::Result<String> {
let mut data = String::new();
{
let mut file = File::open(path.as_ref())?;
file.read_to_string(&mut data)?;
}
Ok(data)
}
fn write_file<P: AsRef<Path>, S: AsRef<[u8]>>(path: P, data: S) -> io::Result<()> {
{
let mut file = OpenOptions::new().write(true).open(path)?;
file.write_all(data.as_ref())?
}
Ok(())
}
fn parse_file<F: FromStr, P: AsRef<Path>>(path: P) -> io::Result<F> where F::Err: Display {
read_file(path)?.trim().parse().map_err(|err| {
io::Error::new(
io::ErrorKind::InvalidData,
format!("{}", err)
)
})
}