Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

The ID of the task is known at the time that the FIFOs need to be
created (it's passed into the IO-creator callback, and is also the same
as the container ID) so there is no need to hardcode it to "init". Name
the FIFOs after the task ID to be consistent with the FIFO names of
exec'ed processes. Delete the now-unused InitProcessName constant so it
can never again be used in place of a task/process ID.

Signed-off-by: Cory Snider <csnider@mirantis.com>

The containerd client is very chatty at the best of times. Because the
libcontained API is stateless and references containers and processes by
string ID for every method call, the implementation is essentially
forced to use the containerd client in a way which amplifies the number
of redundant RPCs invoked to perform any operation. The libcontainerd
remote implementation has to reload the containerd container, task
and/or process metadata for nearly every operation. This in turn
amplifies the number of context switches between dockerd and containerd
to perform any container operation or handle a containerd event,
increasing the load on the system which could otherwise be allocated to
workloads.

Overhaul the libcontainerd interface to reduce the impedance mismatch
with the containerd client so that the containerd client can be used
more efficiently. Split the API out into container, task and process
interfaces which the consumer is expected to retain so that
libcontainerd can retain state---especially the analogous containerd
client objects---without having to manage any state-store inside the
libcontainerd client.

Signed-off-by: Cory Snider <csnider@mirantis.com>

The OOMKilled flag on a container's state has historically behaved
rather unintuitively: it is updated on container exit to reflect whether
or not any process within the container has been OOM-killed during the
preceding run of the container. The OOMKilled flag would be set to true
when the container exits if any process within the container---including
execs---was OOM-killed at any time while the container was running,
whether or not the OOM-kill was the cause of the container exiting. The
flag is "sticky," persisting through the next start of the container;
only being cleared once the container exits without any processes having
been OOM-killed that run.

Alter the behavior of the OOMKilled flag such that it signals whether
any process in the container had been OOM-killed since the most recent
start of the container. Set the flag immediately upon any process being
OOM-killed, and clear it when the container transitions to the "running"
state.

There is an ulterior motive for this change. It reduces the amount of
state the libcontainerd client needs to keep track of and clean up on
container exit. It's one less place the client could leak memory if a
container was to be deleted without going through libcontainerd.

Signed-off-by: Cory Snider <csnider@mirantis.com>

This helps reducing some type-juggling / conversions further up
the stack.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

In dockerd we already have a concept of a "runtime", which specifies the
OCI runtime to use (e.g. runc).
This PR extends that config to add containerd shim configuration.
This option is only exposed within the daemon itself (cannot be
configured in daemon.json).
This is due to issues in supporting unknown shims which will require
more design work.

What this change allows us to do is keep all the runtime config in one
place.

So the default "runc" runtime will just have it's already existing shim
config codified within the runtime config alone.
I've also added 2 more "stock" runtimes which are basically runc+shimv1
and runc+shimv2.
These new runtime configurations are:

- io.containerd.runtime.v1.linux - runc + v1 shim using the V1 shim API
- io.containerd.runc.v2 - runc + shim v2

These names coincide with the actual names of the containerd shims.

This allows the user to essentially control what shim is going to be
used by either specifying these as a `--runtime` on container create or
by setting `--default-runtime` on the daemon.

For custom/user-specified runtimes, the default shim config (currently
shim v1) is used.

Signed-off-by: Brian Goff <cpuguy83@gmail.com>

The following fields are unsupported:

* BlkioStats: all fields other than IoServiceBytesRecursive
* CPUStats: CPUUsage.PercpuUsage
* MemoryStats: MaxUsage and Failcnt

Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>

follow-up to 27552ceb15bca544820229e574427d4c1d6ef585, where this
was left as a review comment, but the PR was already merged.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

full diff: https://github.com/containerd/cgroups/compare/c4b9ac5c7601384c965b9646fc515884e091ebb9...5fbad35c2a7e855762d3c60f2e474ffcad0d470a

- containerd/cgroups#82 Add go module support
- containerd/cgroups#96 Move metrics proto package to stats/v1
- containerd/cgroups#97 Allow overriding the default /proc folder in blkioController
- containerd/cgroups#98 Allows ignoring memory modules
- containerd/cgroups#99 Add Go 1.13 to Travis
- containerd/cgroups#100 stats/v1: export per-cgroup stats

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Add NewContainerOpts to libcontainerd.Create