This patch adds support for modifying settings for the default cgroups;
init, user, and system, as well as adding up to a total of eight groups
for the system.
Services can now be assigned to a cgroup, with optional extra settings
for that particular process group. The syntax is slightly contrivied
but follows the overall Finit syntax of prop:value,prop':value', e.g.
cgroup maint cpu.weight:123,mem.max:10000
Starting with the introduction of rlimits, a group of services sharing
the same .conf file can share the same (locally "global") rlimits, and
now also the same cgroup, e.g.
cgroup.maint
service foo
service bar cgroup:mem.max:1000
This puts foo and bar in the same top-level cgroup 'maint', with an
extra memory restriction on bar for max 1000 bytes memory.
NOTE: 'mem.' is a Finit extension, a shorthand for cgroups2 'memory.'
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
More often than not, the file to write to in sysfs changes rather than
the value. This patch changes echo() into a fnwrite(), flipping what
is vsnprintf()'ed, and adds a stupid str() function that converts any
value (float/int/double/uint64_t) to a static string buffer.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Replaces previous cgreaper.sh functionality for release notification and
cleanup of service groups.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Since the cgroups support in Finit is not yet officially released, we
decided to change the back-end to use cgroups v2 instead of the aging
and rather clumsy cgroups v1. Even this initial refactor is a lot
easier to read and understand, more can still be done since there's
a lot of concepts, data values and the ilk that can now be shared
between different controllers.
Still ToDo: inotify for cgroup.events to clean up leaf nodes, which
in cgroups v1 was handled by cgreaper.sh. This is fixed
in the next commit in the series.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Even systemd have collapsed a few of the cgroup controllers into a
semi-unified hierarchy and uses this approach. We just take it to
the extreme and have collapsed all of them (like cgroup v2).
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
- Fix obvious refactor mistake in cpu.shares assignment
- For unified memory hierarchy we need to set .use_hierarch=1
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
As of now, the default finit cgroup behavior is to use a unified
hierarchy of controllers under /sys/fs/cgroup/finit.
We mount cpu,cpuacct,cpuset,memory (if available) and gain the
ability to control our three major groups: init, system, user.
The default CPU share setup is ~10% for init and user, and 90% for
system. These are guaranteed CPU shares to ensure we do not starve
PID 1 or user processes. Support for configuring these limits will
be added in a later commit.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
- Decleare some return values with (void)fn(), for cases where
we don't care (dropping table headers), or best effor
- Check return value from fgets() and chdir() in some cases that
are valid, i.e., continuing execution is pointless
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
We want to have unique cgroups per instance. I.e., a DHCP client for
eth0 should have its own cgroup separate from a DHCP client for eth1.
Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
Similar to how systemd creates cgroups for all services, for purposes of
tracking, Finit now does the same. We also mount all available cgroups
in the /sys/fs/cgroup namespace.
This patch adds support for grouping processes in logical cgroups, like
systemd, and an `initctl ps` command to list the hieararchy.
Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
Joachim Wiberg