Only log at LOG_INFO level, i.e. make this informational. During start
let's leave it at LOG_WARNING though.
Of course, it's ugly leaving processes around like that either in start
or in stop, but at start its more dangerous than on stop, so be tougher
there.
Indicates that the tags list cannot be modified by notify_message function.
Since the tags list is created only once for multiple call to
notify_message functions.
In all the other cases, I think the code was clearer with the static table.
Here, not so much. And because of the existing dump code, the vtables cannot
be made static and need to remain exported. I still think it's worth to do the
change to have the cmdline introspection, but I'm disappointed with how this
came out.
With cgroup v2 the cgroup freezer is implemented as a cgroup
attribute called cgroup.freeze. cgroup can be frozen by writing "1"
to the file and kernel will send us a notification through
"cgroup.events" after the operation is finished and processes in the
cgroup entered quiescent state, i.e. they are not scheduled to
run. Writing "0" to the attribute file does the inverse and process
execution is resumed.
This commit exposes above low-level functionality through systemd's DBus
API. Each unit type must provide specialized implementation for these
methods, otherwise, we return an error. So far only service, scope, and
slice unit types provide the support. It is possible to check if a
given unit has the support using CanFreeze() DBus property.
Note that DBus API has a synchronous behavior and we dispatch the reply
to freeze/thaw requests only after the kernel has notified us that
requested operation was completed.
Just as log_full already does, check if the log level would result in
logging immediately in the macro in order to avoid doing
unnecessary work that adds up in hot spots.
Scheduling devices after a given unit can be useful to start device *jobs* at a
specific time in the transaction, see commit 4195077ab4.
This (hidden) change was introduced by commit eef85c4a3f.
UnitStatusMessageFormats.finished_job, if present,
will be called with the same arguments as
job_get_done_status_message_format() to provide a format string
appropriate for the context
This commit replaces "Started" with "Finished" for started oneshot
units, as mentioned in the referenced issue
Closes#2458.
We would flip to status=temporary mode on the first error, and then switch back
to status=auto after the initial transaction was done. This isn't very useful,
because usually all the messages about successfully started units and not
related to the original failure. In fact, all those messages most likely cause
the information about the prime error to scroll off screen. And if the user
requested quiet boot, there's no reason to think that they care about those
success messages.
Also, when logging about dependency cycles, treat this similarly to a unit
error and show the message even if the status is "soft disabled" (before we
wouldn't show it in that case).
This way we shuld be able to order mounts properly against their backing
services in case complex storage is used (i.e. LUKS), even if the device
path used for mounting the devices is different from the expected device
node of the backing service.
Specifically, if we have a LUKS device /dev/mapper/foo that is mounted
by this name all is trivial as the relationship can be established a
priori easily. But if it is mounted via a /dev/disk/by-uuid/ symlink or
similar we only can relate the device node generated to the one mounted
at the moment the device is actually established. That's because the
UUID of the fs is stored inside the encrypted volume and thus not
knowable until the volume is set up. This patch tries to improve on this
situation: a implicit After=blockdev@.target dependency is generated for
all mounts, based on the data from /proc/self/mountinfo, which should be
the actual device node, with all symlinks resolved. This means that as
soon as the mount is established the ordering via blockdev@.target will
work, and that means during shutdown it is honoured, which is what we
are looking for.
Note that specifying /etc/fstab entries via UUID= for LUKS devices still
sucks and shouldn't be done, because it means we cannot know which LUKS
device to activate to make an fs appear, and that means unless the
volume is set up at boot anyway we can't really handle things
automatically when putting together transactions that need the mount.
Similar, refuse triggering deps on units that cannot trigger.
And rework how we ignore After= dependencies on device units, to work
the same way.
See: #14142
Previously, when first connecting to the bus after connecting to it we'd
issue a ListNames() bus call to the driver to figure out which bus names
are currently active. This information was then used to initialize the
initial state for services that use BusName=.
This change removes the whole code for this and replaces it with
something vastly simpler.
First of all, the ListNames() call was issues synchronosuly, which meant
if dbus was for some reason synchronously calling into PID1 for some
reason we'd deadlock. As it turns out there's now a good chance it does:
the nss-systemd userdb hookup means that any user dbus-daemon resolves
might result in a varlink call into PID 1, and dbus resolves quite a lot
of users while parsing its policy. My original goal was to fix this
deadlock.
But as it turns out we don't need the ListNames() call at all anymore,
since #12957 has been merged. That PR was supposed to fix a race where
asynchronous installation of bus matches would cause us missing the
initial owner of a bus name when a service is first started. It fixed it
(correctly) by enquiring with GetOwnerName() who currently owns the
name, right after installing the match. But this means whenever we start watching a bus name we anyway
issue a GetOwnerName() for it, and that means also when first connecting
to the bus we don't need to issue ListNames() anymore since that just
tells us the same info: which names are currently owned.
hence, let's drop ListNames() and instead make better use of the
GetOwnerName() result: if it failed the name is not owned.
Also, while we are at it, let's simplify the unit's owner_name_changed()
callback(): let's drop the "old_owner" argument. We never used that
besides logging, and it's hard to synthesize from just the return of a
GetOwnerName(), hence don't bother.
unit_load_fragment_and_dropin() and unit_load_fragment_and_dropin_optional()
are really the same, with one minor difference in behaviour. Let's drop
the second function.
"_optional" in the name suggests that it's the "dropin" part that is optional.
(Which it is, but in this case, we mean the fragment to be optional.)
I think the new version with a flag is easier to understand.
v2:
- if RestartKillSignal= is not specified, fall back to KillSignal=. This is necessary
to preserve backwards compatibility (and keep KillSignal= generally useful).
"ratelimit" is a real word, so we don't need to use the other form anywhere.
We had both forms in various places, let's standarize on the shorter and more
correct one.
In high load scenarios it is possible for services to be started
before the NameOwnerChanged signal is properly installed.
Emulate a callback by also queuing a GetNameOwner when the match is
installed.
Fixes: #12956
This adds basic infrastructure to implement a "clean" operation for unit
types. This "clean" operation is supposed to remove on-disk resources of
units, and is supposed to be used in a later commit to clean our
RuntimeDirectory=, StateDirectory= and so on of service units.
Later commits will open this up to the bus, and hook up service units
with this.
This also adds a new generic ActiveState called UNIT_MAINTENANCE. It's
supposed to cover all kinds of "maintainance" state of units.
Specifically, this is supposed to cover the "cleaning" operations later
added for service units which might take a bit of time. This high-level,
generic, abstract state is called UNIT_MAINTENANCE instead of the
more specific "UNIT_CLEANING", since I think this should be kept open
for different operations possibly later on that could be nicely subsumed
under this (for example, maybe a recursive chown()ing operation could be
covered by this, and similar).
Takes a single /sys/fs/bpf/pinned_prog string as argument, but may be
specified multiple times. An empty assignment resets all previous filters.
Closes https://github.com/systemd/systemd/issues/10227
This was the last kind of accounting still not exposed on for each unit.
Let's fix that.
Note that this is a relatively simplistic approach: we don't expose
per-device stats, but sum them all up, much like cgtop does. This kind
of metric is probably the most interesting for most usecases, and covers
the "systemctl status" output best. If we want per-device stats one day
we can of course always add that eventually.
This adds a new per-service OOMPolicy= (along with a global
DefaultOOMPolicy=) that controls what to do if a process of the service
is killed by the kernel's OOM killer. It has three different values:
"continue" (old behaviour), "stop" (terminate the service), "kill" (let
the kernel kill all the service's processes).
On top of that, track OOM killer events per unit: generate a per-unit
structured, recognizable log message when we see an OOM killer event,
and put the service in a failure state if an OOM killer event was seen
and the selected policy was not "continue". A new "result" is defined
for this case: "oom-kill".
All of this relies on new cgroupv2 kernel functionality: the
"memory.events" notification interface and the "memory.oom.group"
attribute (which makes the kernel kill all cgroup processes
automatically).
Let's rename the .cgroup_inotify_wd field of the Unit object to
.cgroup_control_inotify_wd. Let's similarly rename the hashmap
.cgroup_inotify_wd_unit of the Manager object to
.cgroup_control_inotify_wd_unit.
Why? As preparation for a later commit that allows us to watch the
"memory.events" cgroup attribute file in addition to the "cgroup.events"
file we already watch with the fields above. In that later commit we'll
add new fields "cgroup_memory_inotify_wd" to Unit and
"cgroup_memory_inotify_wd_unit" to Manager, that are used to watch these
other events file.
No change in behaviour. Just some renaming.
Some PIDs can remain in the watched list even though their processes have
exited since a long time. It can easily happen if the main process of a forking
service manages to spawn a child before the control process exits for example.
However when a pid is about to be mapped to a unit by calling unit_watch_pid(),
the caller usually knows if the pid should belong to this unit exclusively: if
we just forked() off a child, then we can be sure that its PID is otherwise
unused. In this case we take this opportunity to remove any stalled PIDs from
the watched process list.
If we learnt about a PID in any other form (for example via PID file, via
searching, MAINPID= and so on), then we can't assume anything.
Just some renaming, no change in behaviour.
Background: I'd like to add more functions unit_test_xyz() that test
various things, hence let's streamline the naming a bit.
KillMode=mixed and control group are used to indicate that all
process should be killed off. SendSIGKILL is used for services
that require a clean shutdown. These are typically database
service where a SigKilled process would result in a lengthy
recovery and who's shutdown or startup time is quite variable
(so Timeout settings aren't of use).
Here we take these two factors and refuse to start a service if
there are existing processes within a control group. Databases,
while generally having some protection against multiple instances
running, lets not stress the rigor of these. Also ExecStartPre
parts of the service aren't as rigoriously written to protect
against against multiple use.
closes#8630
Nitpicky, but we've used a lot of random spacings and names in the past,
but we're trying to be completely consistent on "cgroup vN" now.
Generated by `fd -0 | xargs -0 -n1 sed -ri --follow-symlinks 's/cgroups? ?v?([0-9])/cgroup v\1/gI'`.
I manually ignored places where it's not appropriate to replace (eg.
"cgroup2" fstype and in src/shared/linux).
It would be very wrong if any of the specfier printf calls modified
any of the objects or data being printed. Let's mark all arguments as const
(primarily to make it easier for the reader to see where modifications cannot
occur).
This adds SuccessActionExitStatus= and FailureActionExitStatus= that may
be used to configure the exit status to propagate in when
SuccessAction=exit or FailureAction=exit is used.
When not specified let's also propagate the exit status of the main
process we fork off for the unit.
Zbigniew Jędrzejewski-Szmek