The main purpose of this patch is to remove top-level cgroups when they
are remvoed from finit.conf. However, this is tricky, becasue there may
still be supervised services (and children of them) running. We must
postpone removal until a cgroup.events change. To make matters worse,
events may arrive out-of-order, i.e. the last-child event for the parent
cgroup before the sub-group.
A spin-off from this patch is that we can now support arbitrarily long
group names and group config. (Only applies to top-level cgroups, not
run/task/services.)
Limitations:
- Processes in "removed" cgroups are not migrated/orphaned, the reasons
are several: overhead and complexity and the fact that memory cannot
be migrated
- A lingering child of a moved service may prevent an old top-level
cgroup from being removed.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
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>
- Use iwatch, modeled after pidfile plugin
- Use one .conf watcher for all *.conf paths/files
- Use full path of conf file for changes, from realpath().
This fixes a long-standing limitation on unique filenames
for services, that absolutely nobody knew about
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Up until now Finit has only read /proc/cmdline to determine debug level,
single user mode, etc. This patch is one in a series to make enable it
to run also in containers.
Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
This patch is an optimization. Now that we monitor for any .conf file
changes (as soon as the event loop starts) we can skip automatic reload
of all .conf files and services if no .conf file has changed. Unless
the user issues an `initctl reload`, `init q`, or sends us SIGHUP.
Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
Until now Finit has used mtime to determine if a file has been changed,
or simply touched to request reload, when `initctl reload` is called.
Using mtime for this purpose is a monumentally bad idea since time can
be changed at any point: a user may adjust the time, NTP continously
tunes the clock, and time stamps are stored as the walltime. So if we
compare timestamps against the last time we (booted or) did reload, we
would miss .conf file changes.
This patch replaces the mtime mistake with an inotify watcher for the
following files: /etc/finit.d/*.conf, /etc/finit.d/available/*.conf,
and /etc/finit.conf. All file changes between (bootstraps and) calls
to `initctl reload` are tracked, like the mtime backend it replaces.
Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
This patch extends the existing rlimit implementation to support setting
limits per service, run/task, inetd, and tty.
Use rlimit in /etc/finit.conf to change the global setting, which is
then inherited to each /etc/finit.d/*.conf. For each .conf file the
rlimit is reinitialized to the global finit.conf settings.
Also, add `unlimited` keyword, to replace the now deprecated `infinity`
keyword. The latter is however kept, for compatibility with previous
releases, for the foreseeable future.
Signed-off-by: Joachim Nilsson <troglobit@gmail.com>
Joachim Wiberg