diff options
Diffstat (limited to 'src/linux.rs')
| -rw-r--r-- | src/linux.rs | 104 |
1 files changed, 54 insertions, 50 deletions
diff --git a/src/linux.rs b/src/linux.rs index 671a943..36f4727 100644 --- a/src/linux.rs +++ b/src/linux.rs @@ -18,7 +18,7 @@ macro_rules! debug { } macro_rules! some { - ($e:expr) => ({ + ($e:expr) => {{ match $e { Some(v) => v, None => { @@ -26,7 +26,7 @@ macro_rules! some { return None; } } - }) + }}; } pub fn get_num_cpus() -> usize { @@ -126,18 +126,15 @@ fn init_cgroups() { // Should only be called once debug_assert!(CGROUPS_CPUS.load(Ordering::SeqCst) == 0); - match load_cgroups("/proc/self/cgroup", "/proc/self/mountinfo") { - Some(quota) => { - if quota == 0 { - return; - } + if let Some(quota) = load_cgroups("/proc/self/cgroup", "/proc/self/mountinfo") { + if quota == 0 { + return; + } - let logical = logical_cpus(); - let count = ::std::cmp::min(quota, logical); + let logical = logical_cpus(); + let count = ::std::cmp::min(quota, logical); - CGROUPS_CPUS.store(count, Ordering::SeqCst); - } - None => return, + CGROUPS_CPUS.store(count, Ordering::SeqCst); } } @@ -167,18 +164,14 @@ struct Subsys { impl Cgroup { fn new(dir: PathBuf) -> Cgroup { - Cgroup { - base: dir, - } + Cgroup { base: dir } } fn translate(mntinfo: MountInfo, subsys: Subsys) -> Option<Cgroup> { // Translate the subsystem directory via the host paths. debug!( "subsys = {:?}; root = {:?}; mount_point = {:?}", - subsys.base, - mntinfo.root, - mntinfo.mount_point + subsys.base, mntinfo.root, mntinfo.mount_point ); let rel_from_root = some!(Path::new(&subsys.base).strip_prefix(&mntinfo.root).ok()); @@ -238,13 +231,27 @@ impl MountInfo { fn parse_line(line: String) -> Option<MountInfo> { let mut fields = line.split(' '); + // 7 5 0:6 </> /sys/fs/cgroup/cpu,cpuacct rw,nosuid,nodev,noexec,relatime shared:7 - cgroup cgroup rw,cpu,cpuacct let mnt_root = some!(fields.nth(3)); - let mnt_point = some!(fields.nth(0)); + // 7 5 0:6 / </sys/fs/cgroup/cpu,cpuacct> rw,nosuid,nodev,noexec,relatime shared:7 - cgroup cgroup rw,cpu,cpuacct + let mnt_point = some!(fields.next()); + + // Ignore all fields until the separator(-). + // Note: there could be zero or more optional fields before hyphen. + // See: https://man7.org/linux/man-pages/man5/proc.5.html + // 7 5 0:6 / /sys/fs/cgroup/cpu,cpuacct rw,nosuid,nodev,noexec,relatime shared:7 <-> cgroup cgroup rw,cpu,cpuacct + // Note: we cannot use `?` here because we need to support Rust 1.13. + match fields.find(|&s| s == "-") { + Some(_) => {} + None => return None, + }; - if fields.nth(3) != Some("cgroup") { + // 7 5 0:6 / /sys/fs/cgroup/cpu,cpuacct rw,nosuid,nodev,noexec,relatime shared:7 - <cgroup> cgroup rw,cpu,cpuacct + if fields.next() != Some("cgroup") { return None; } + // 7 5 0:6 / /sys/fs/cgroup/cpu,cpuacct rw,nosuid,nodev,noexec,relatime shared:7 - cgroup cgroup <rw,cpu,cpuacct> let super_opts = some!(fields.nth(1)); // We only care about the 'cpu' option @@ -281,16 +288,18 @@ impl Subsys { return None; } - fields.next().map(|path| Subsys { base: path.to_owned() }) + fields.next().map(|path| Subsys { + base: path.to_owned(), + }) } } #[cfg(test)] mod tests { - use std::path::{Path, PathBuf}; use super::{Cgroup, MountInfo, Subsys}; + use std::path::{Path, PathBuf}; - + // `static_in_const` feature is not stable in Rust 1.13. static FIXTURES_PROC: &'static str = "fixtures/cgroups/proc/cgroups"; static FIXTURES_CGROUPS: &'static str = "fixtures/cgroups/cgroups"; @@ -304,12 +313,29 @@ mod tests { #[test] fn test_load_mountinfo() { + // test only one optional fields let path = join!(FIXTURES_PROC, "mountinfo"); let mnt_info = MountInfo::load_cpu(path).unwrap(); assert_eq!(mnt_info.root, "/"); assert_eq!(mnt_info.mount_point, "/sys/fs/cgroup/cpu,cpuacct"); + + // test zero optional field + let path = join!(FIXTURES_PROC, "mountinfo_zero_opt"); + + let mnt_info = MountInfo::load_cpu(path).unwrap(); + + assert_eq!(mnt_info.root, "/"); + assert_eq!(mnt_info.mount_point, "/sys/fs/cgroup/cpu,cpuacct"); + + // test multi optional fields + let path = join!(FIXTURES_PROC, "mountinfo_multi_opt"); + + let mnt_info = MountInfo::load_cpu(path).unwrap(); + + assert_eq!(mnt_info.root, "/"); + assert_eq!(mnt_info.mount_point, "/sys/fs/cgroup/cpu,cpuacct"); } #[test] @@ -324,12 +350,7 @@ mod tests { #[test] fn test_cgroup_mount() { let cases = &[ - ( - "/", - "/sys/fs/cgroup/cpu", - "/", - Some("/sys/fs/cgroup/cpu"), - ), + ("/", "/sys/fs/cgroup/cpu", "/", Some("/sys/fs/cgroup/cpu")), ( "/docker/01abcd", "/sys/fs/cgroup/cpu", @@ -348,27 +369,10 @@ mod tests { "/docker/01abcd/large", Some("/sys/fs/cgroup/cpu/large"), ), - // fails - - ( - "/docker/01abcd", - "/sys/fs/cgroup/cpu", - "/", - None, - ), - ( - "/docker/01abcd", - "/sys/fs/cgroup/cpu", - "/docker", - None, - ), - ( - "/docker/01abcd", - "/sys/fs/cgroup/cpu", - "/elsewhere", - None, - ), + ("/docker/01abcd", "/sys/fs/cgroup/cpu", "/", None), + ("/docker/01abcd", "/sys/fs/cgroup/cpu", "/docker", None), + ("/docker/01abcd", "/sys/fs/cgroup/cpu", "/elsewhere", None), ( "/docker/01abcd", "/sys/fs/cgroup/cpu", @@ -387,7 +391,7 @@ mod tests { }; let actual = Cgroup::translate(mnt_info, subsys).map(|c| c.base); - let expected = expected.map(|s| PathBuf::from(s)); + let expected = expected.map(PathBuf::from); assert_eq!(actual, expected); } } |