moby/pkg/sysinfo/sysinfo.go
Erik St. Martin 56f77d5ade Implementing support for --cpu-rt-period and --cpu-rt-runtime so that
containers may specify these cgroup values at runtime. This will allow
processes to change their priority to real-time within the container
when CONFIG_RT_GROUP_SCHED is enabled in the kernel. See #22380.

Also added sanity checks for the new --cpu-rt-runtime and --cpu-rt-period
flags to ensure that that the kernel supports these features and that
runtime is not greater than period.

Daemon will support a --cpu-rt-runtime flag to initialize the parent
cgroup on startup, this prevents the administrator from alotting runtime
to docker after each restart.

There are additional checks that could be added but maybe too far? Check
parent cgroups to ensure values are <= parent, inspecting rtprio ulimit
and issuing a warning.

Signed-off-by: Erik St. Martin <alakriti@gmail.com>
2016-10-26 11:33:06 -04:00

144 lines
3.7 KiB
Go

package sysinfo
import "github.com/docker/docker/pkg/parsers"
// SysInfo stores information about which features a kernel supports.
// TODO Windows: Factor out platform specific capabilities.
type SysInfo struct {
// Whether the kernel supports AppArmor or not
AppArmor bool
// Whether the kernel supports Seccomp or not
Seccomp bool
cgroupMemInfo
cgroupCPUInfo
cgroupBlkioInfo
cgroupCpusetInfo
cgroupPids
// Whether IPv4 forwarding is supported or not, if this was disabled, networking will not work
IPv4ForwardingDisabled bool
// Whether bridge-nf-call-iptables is supported or not
BridgeNFCallIPTablesDisabled bool
// Whether bridge-nf-call-ip6tables is supported or not
BridgeNFCallIP6TablesDisabled bool
// Whether the cgroup has the mountpoint of "devices" or not
CgroupDevicesEnabled bool
}
type cgroupMemInfo struct {
// Whether memory limit is supported or not
MemoryLimit bool
// Whether swap limit is supported or not
SwapLimit bool
// Whether soft limit is supported or not
MemoryReservation bool
// Whether OOM killer disable is supported or not
OomKillDisable bool
// Whether memory swappiness is supported or not
MemorySwappiness bool
// Whether kernel memory limit is supported or not
KernelMemory bool
}
type cgroupCPUInfo struct {
// Whether CPU shares is supported or not
CPUShares bool
// Whether CPU CFS(Completely Fair Scheduler) period is supported or not
CPUCfsPeriod bool
// Whether CPU CFS(Completely Fair Scheduler) quota is supported or not
CPUCfsQuota bool
// Whether CPU real-time period is supported or not
CPURealtimePeriod bool
// Whether CPU real-time runtime is supported or not
CPURealtimeRuntime bool
}
type cgroupBlkioInfo struct {
// Whether Block IO weight is supported or not
BlkioWeight bool
// Whether Block IO weight_device is supported or not
BlkioWeightDevice bool
// Whether Block IO read limit in bytes per second is supported or not
BlkioReadBpsDevice bool
// Whether Block IO write limit in bytes per second is supported or not
BlkioWriteBpsDevice bool
// Whether Block IO read limit in IO per second is supported or not
BlkioReadIOpsDevice bool
// Whether Block IO write limit in IO per second is supported or not
BlkioWriteIOpsDevice bool
}
type cgroupCpusetInfo struct {
// Whether Cpuset is supported or not
Cpuset bool
// Available Cpuset's cpus
Cpus string
// Available Cpuset's memory nodes
Mems string
}
type cgroupPids struct {
// Whether Pids Limit is supported or not
PidsLimit bool
}
// IsCpusetCpusAvailable returns `true` if the provided string set is contained
// in cgroup's cpuset.cpus set, `false` otherwise.
// If error is not nil a parsing error occurred.
func (c cgroupCpusetInfo) IsCpusetCpusAvailable(provided string) (bool, error) {
return isCpusetListAvailable(provided, c.Cpus)
}
// IsCpusetMemsAvailable returns `true` if the provided string set is contained
// in cgroup's cpuset.mems set, `false` otherwise.
// If error is not nil a parsing error occurred.
func (c cgroupCpusetInfo) IsCpusetMemsAvailable(provided string) (bool, error) {
return isCpusetListAvailable(provided, c.Mems)
}
func isCpusetListAvailable(provided, available string) (bool, error) {
parsedProvided, err := parsers.ParseUintList(provided)
if err != nil {
return false, err
}
parsedAvailable, err := parsers.ParseUintList(available)
if err != nil {
return false, err
}
for k := range parsedProvided {
if !parsedAvailable[k] {
return false, nil
}
}
return true, nil
}
// Returns bit count of 1, used by NumCPU
func popcnt(x uint64) (n byte) {
x -= (x >> 1) & 0x5555555555555555
x = (x>>2)&0x3333333333333333 + x&0x3333333333333333
x += x >> 4
x &= 0x0f0f0f0f0f0f0f0f
x *= 0x0101010101010101
return byte(x >> 56)
}