Now that listen_fds() have been split out, we can safely move the allocation
of the manager object after doing the forking (the fork is done to notify legcay
init-systems that the fds are ready).
Subsequently, we can merge manager_listen() back into managre_new().
This entails a minor behaviour change: the application of permissions to
static device nodes now happens after the fork (but still before notifying
systemd about being ready).
This will simply silently fail on non-systemd systems, so there is no reason
to make it conditional.
Also make it clear that we notify systemd about being ready as the last step
before starting the event loop, whereas the forking might need to happen
earlier.
This should have no behavioural change, but it is odd to tie the cgroup cleaning to
whether or not we are passed sockets.
The point really is if we are guaranteed to be in a dedicated cgroup, so instead
check for our parent being PID1 (we already implicitly only do this on systemd
systems).
We used to block all signals, and restore the original signal mask before exec'ing
external processes.
Now we just block the signals we care about and unconditionally unblock all signals
before exec'ing.
The communication channels must all be opened before forknig in daemon mode,
or we cannot guarantee that udevadm will work correctly as soon as udevd is
started.
Only log about starting in daemon mode, rely on PID1 to log this in notify mode. Also
explicitly set the STATUS variable, as is done in notify mode as is done for other
serivecs.
This allows us to drop the special sigterm handling in spawn_wait()
as this will now be passed directly to the worker event loop.
We now log failing spawend processes at 'warning' level, and timeouts
are in terms of CLOCK_BOOTTIME when available, otherwise the behavior
is unchanged.
Rather than trying to schedule new events on every main-loop iteration, do it explicitly when
processing an event finishes, a worker is killed, a new uevent is received, or the event queue
is explicitly restarted.
The behavior is mostly unchanged, but rather than only ever calling these functions at
fixed points in the event loop, they are called directly whenever they are invoked.
This partly reverts:
commit 6d1b1e0bc6
Author: Tom Gundersen <teg@jklm.no>
Date: Sun May 24 15:10:04 2015 +0200
udevd: worker - fully clean up unnecessary fds
The inotify-fd _is_ used in the workers, so don't close it! Have a look at
udev-watch.c, which keeps track of the inotify-fd as a global variable
(ugh!).
We would enforce that events could only be added to the queue from the
main process, but that brake in daemonized mode. Relax the restriction
to only allow one process to add events to the queue.
Reported by Mantas Mikulėnas.
We were returning rather than continuing in some cases. The intention
was always to fully process all pending events before returning
from the SIGCHLD handler. Restore this behaviour.
This way it is more obvious that the queue flag file is always
up-to-date. Moreover, we only have to touch/unlink it when the
first/last event is allocated/freed.
This avoids updating the flag files twice for every loop, and also removes another dependency
in the main-loop, so we are freer to reshufle it as we want.
Rather than skippling ctrl handling whenever we have handlede inotify events
(and hence may have synthesized a 'change' event), just call the uevent
handling explicitly from on_inotify() so that the event queue is up-to-date.
Make the worker context have the same life-span as the worker process. It is created on fork()
and free'd on SIGCHLD.
The change means that we can get worker_returned() for a worker context that is no longer around,
this is not a problem and we can just drop the message. The only use for worker_returned() is to
know to reschedule events to workers that are still around, so if the worker has already exited
it is not important to keep track of. We still print a debug statement in this case to be on the
safe side.
