hostifo: update LXC, add Cloud Run.

Recent LXC support no longer has "lxc" in /proc/1/cgroup:
    # cat /proc/1/cgroup
    12:freezer:/
    11:rdma:/
    10:cpuset:/
    9:pids:/
    8:blkio:/
    7:devices:/
    6:perf_event:/
    5:net_cls,net_prio:/
    4:memory:/
    3:hugetlb:/
    2:cpu,cpuacct:/
    1:name=systemd:/init.scope
    0::/init.scope

Look for fuse.lxcfs in /proc.mounts in addition:
    # grep lxc /proc/mounts
    lxcfs /proc/cpuinfo fuse.lxcfs ...
    lxcfs /proc/diskstats fuse.lxcfs ...
    lxcfs /proc/loadavg fuse.lxcfs ...
    lxcfs /proc/meminfo fuse.lxcfs ...
    lxcfs /proc/stat fuse.lxcfs ...
    lxcfs /proc/swaps fuse.lxcfs ...
    lxcfs /proc/uptime fuse.lxcfs ...
    lxcfs /sys/devices/system/cpu/online fuse.lxcfs ...

Add Knative detection by looking for the environment variables
which are part of its container contract.

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
This commit is contained in:
Denton Gentry 2021-04-02 00:08:58 -07:00 committed by Denton Gentry
parent 57756ef673
commit 224e60cef2

View File

@ -11,6 +11,7 @@
"fmt"
"io"
"io/ioutil"
"os"
"strings"
"syscall"
@ -58,6 +59,9 @@ func osVersionLinux() string {
if inContainer() {
attrBuf.WriteString("; container")
}
if inKnative() {
attrBuf.WriteString("; env=kn")
}
attr := attrBuf.String()
id := m["ID"]
@ -99,5 +103,21 @@ func inContainer() (ret bool) {
}
return nil
})
lineread.File("/proc/mounts", func(line []byte) error {
if mem.Contains(mem.B(line), mem.S("fuse.lxcfs")) {
ret = true
return io.EOF
}
return nil
})
return
}
func inKnative() bool {
// https://cloud.google.com/run/docs/reference/container-contract#env-vars
if os.Getenv("K_REVISION") != "" && os.Getenv("K_CONFIGURATION") != "" &&
os.Getenv("K_SERVICE") != "" && os.Getenv("PORT") != "" {
return true
}
return false
}