The MANAGER_TEST_RUN_IGNORE_DEPENDENCIES flag was added in order to allow the caller
to skip the recursive loading of dependency units when loading specific
unit files. This includes the default dependencies, the specified dependencies, the slice.
This will be used by systemd-analyze to allow checking individual unit files in isolation.
The unit queues are not serialized/deserialized (they are recreated
after reexec/reload instead). The destroyed units are not removed from
the cgroup_oom_queue. That means the queue may contain possibly invalid
pointers to released units.
Fix this by removing the units from cgroup_oom_queue as we do for
others. When at it, sync assert checks with currently existing queues
and put them in order in the manager cleanup code.
While reexec/reload, we drop the inotify watch on cgroup file(s), so
we need to re-check them in case they changed and we missed the event.
Fixes: #20198
In general we almost never hit those asserts in production code, so users see
them very rarely, if ever. But either way, we just need something that users
can pass to the developers.
We have quite a few of those asserts, and some have fairly nice messages, but
many are like "WTF?" or "???" or "unexpected something". The error that is
printed includes the file location, and function name. In almost all functions
there's at most one assert, so the function name alone is enough to identify
the failure for a developer. So we don't get much extra from the message, and
we might just as well drop them.
Dropping them makes our code a tiny bit smaller, and most importantly, improves
development experience by making it easy to insert such an assert in the code
without thinking how to phrase the argument.
See https://bugzilla.redhat.com/show_bug.cgi?id=1973058:
we would log something like:
systemd[244]: Starting willskip.service...
systemd[244]: willskip.service: Control process exited, code=exited, status=2/INVALIDARGUMENT
systemd[244]: willskip.service: Skipped due to 'exec-condition'.
systemd[244]: Condition check resulted in willskip.service being skipped.
The line with 'Control process exited' would be at LOG_NOTICE level.
With the patch:
systemd[244]: Starting willskip.service...
systemd[244]: willskip.service: Skipped due to 'exec-condition'.
systemd[244]: Condition check resulted in willskip.service being skipped.
Debug logs:
systemd[244]: Starting willskip.service...
systemd[244]: Sent message type=signal sender=org.freedesktop.systemd1 destination=n/a path=/org/freedesktop/systemd1/unit/willskip_2eservice interface=org.freedesktop.DBus.Properties member=PropertiesChanged cookie=8 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a
systemd[244]: Sent message type=signal sender=org.freedesktop.systemd1 destination=n/a path=/org/freedesktop/systemd1/unit/willskip_2eservice interface=org.freedesktop.DBus.Properties member=PropertiesChanged cookie=9 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a
systemd[244]: Sent message type=signal sender=org.freedesktop.systemd1 destination=n/a path=/org/freedesktop/systemd1/job/46 interface=org.freedesktop.DBus.Properties member=PropertiesChanged cookie=10 reply_cookie=0 signature=sa{sv}as error-name=n/a error-message=n/a
systemd[11020]: Skipping PR_SET_MM, as we don't have privileges.
systemd[11020]: willskip.service: Executing: sh -c 'exit 2'
systemd[244]: Received SIGCHLD from PID 11020 (sh).
systemd[244]: Child 11020 (sh) died (code=exited, status=2/INVALIDARGUMENT)
systemd[244]: willskip.service: Child 11020 belongs to willskip.service.
systemd[244]: willskip.service: Condition check process exited, code=exited, status=2/INVALIDARGUMENT (success)
systemd[244]: willskip.service: Got final SIGCHLD for state condition.
systemd[244]: willskip.service: Skipped due to 'exec-condition'.
systemd[244]: willskip.service: Service will not restart (restart setting)
systemd[244]: willskip.service: Changed condition -> dead
systemd[244]: willskip.service: Job 46 willskip.service/start finished, result=done
systemd[244]: Condition check resulted in willskip.service being skipped.
The code to print unit status formats had a long history, and became a
hard-to-manage mess of duplicate code parts. We would use sprintf() to
format a string, and then call sprintf() again… The code is reworked
to avoid repeated formattings and to streamline printing to the log
and the console.
The approach used in this patch is a bit more complex then in patches by Colin
Walter and Paweł Marciniak, because an allocation is only done if "combined"
format is used. In other cases we return the existing ->id or ->description
strings. The caller can also control whether a shorter or longer status string
should be used. This way the caller can use a shorter format where it makes
sense, for example in the cylon eye output, where we don't have enough
horizontal space.
Patch is based on Colin Walters' https://github.com/systemd/systemd/pull/15957,
and Paweł Marciniak's patch posted on fedora-devel.
Note: for some reason, the functions for printing of start and stop messages
were sepearated by some unrelated functions. They are moved to be consecutive,
but this makes the much more verbose than it would be otherwise. I found it
useful to view in gitk's "new" mode.
Co-authored-by: Colin Walters <walters@verbum.org>
Co-authored-by: Paweł Marciniak <sunwire+git@gmail.com>
Output from a Fedora Rawhide container boot (w/ some follow-up patches to
tweak Descriptions):
Welcome to Fedora 35 (Rawhide Prerelease)!
Queued start job for default target graphical.target.
[ OK ] Created slice system-getty.slice - Slice /system/getty.
[ OK ] Created slice system-modprobe.slice - Slice /system/modprobe.
[ OK ] Created slice system-sshd\x2dkeygen.slice - Slice /system/sshd-keygen.
[ OK ] Created slice user.slice - User and Session Slice.
[ OK ] Started systemd-ask-password-console.path - Dispatch Password Requests to Console Directory Watch.
[ OK ] Started systemd-ask-password-wall.path - Forward Password Requests to Wall Directory Watch.
[ OK ] Reached target cryptsetup.target - Local Encrypted Volumes.
[ OK ] Reached target paths.target - Path Units.
[ OK ] Reached target remote-cryptsetup.target - Remote Encrypted Volumes.
[ OK ] Reached target remote-fs.target - Remote File Systems.
[ OK ] Reached target slices.target - Slice Units.
[ OK ] Reached target swap.target - Swaps.
[ OK ] Reached target veritysetup.target - Local Verity Integrity Protected Volumes.
[ OK ] Listening on systemd-coredump.socket - Process Core Dump Socket.
[ OK ] Listening on systemd-initctl.socket - initctl Compatibility Named Pipe.
[ OK ] Listening on systemd-journald-dev-log.socket - Journal Socket (/dev/log).
[ OK ] Listening on systemd-journald.socket - Journal Socket.
[ OK ] Listening on systemd-networkd.socket - Network Service Netlink Socket.
[ OK ] Listening on systemd-userdbd.socket - User Database Manager Socket.
Mounting dev-hugepages.mount - Huge Pages File System...
Starting systemd-journald.service - Journal Service...
Starting systemd-remount-fs.service - Remount Root and Kernel File Systems...
Starting systemd-sysctl.service - Apply Kernel Variables...
[ OK ] Mounted dev-hugepages.mount - Huge Pages File System.
[ OK ] Finished systemd-remount-fs.service - Remount Root and Kernel File Systems.
Starting systemd-hwdb-update.service - Rebuild Hardware Database...
Starting systemd-sysusers.service - Create System Users...
[ OK ] Finished systemd-sysctl.service - Apply Kernel Variables.
[ OK ] Started systemd-journald.service - Journal Service.
Starting systemd-journal-flush.service - Flush Journal to Persistent Storage...
[ OK ] Finished systemd-sysusers.service - Create System Users.
Starting systemd-tmpfiles-setup-dev.service - Create Static Device Nodes in /dev...
[ OK ] Finished systemd-tmpfiles-setup-dev.service - Create Static Device Nodes in /dev.
[ OK ] Reached target local-fs-pre.target - Preparation for Local File Systems.
[ OK ] Reached target local-fs.target - Local File Systems.
[ OK ] Reached target machines.target - Containers.
Starting dracut-shutdown.service - Restore /run/initramfs on shutdown...
Starting ldconfig.service - Rebuild Dynamic Linker Cache...
[ OK ] Finished dracut-shutdown.service - Restore /run/initramfs on shutdown.
[ OK ] Finished ldconfig.service - Rebuild Dynamic Linker Cache.
[ OK ] Finished systemd-journal-flush.service - Flush Journal to Persistent Storage.
Starting systemd-tmpfiles-setup.service - Create Volatile Files and Directories...
[ OK ] Finished systemd-tmpfiles-setup.service - Create Volatile Files and Directories.
Starting systemd-journal-catalog-update.service - Rebuild Journal Catalog...
Starting systemd-oomd.service - Userspace Out-Of-Memory (OOM) Killer...
Starting systemd-update-utmp.service - Update UTMP about System Boot/Shutdown...
Starting systemd-userdbd.service - User Database Manager...
[ OK ] Finished systemd-update-utmp.service - Update UTMP about System Boot/Shutdown.
[ OK ] Finished systemd-journal-catalog-update.service - Rebuild Journal Catalog.
[ OK ] Started systemd-userdbd.service - User Database Manager.
[ OK ] Started systemd-oomd.service - Userspace Out-Of-Memory (OOM) Killer.
[ OK ] Finished systemd-hwdb-update.service - Rebuild Hardware Database.
Starting systemd-networkd.service - Network Configuration...
Starting systemd-update-done.service - Update is Completed...
[ OK ] Finished systemd-update-done.service - Update is Completed.
[ OK ] Reached target sysinit.target - System Initialization.
[ OK ] Started dnf-makecache.timer - dnf makecache --timer.
[ OK ] Started logrotate.timer - Daily rotation of log files.
[ OK ] Started systemd-tmpfiles-clean.timer - Daily Cleanup of Temporary Directories.
[ OK ] Reached target timers.target - Timer Units.
[ OK ] Listening on dbus.socket - D-Bus System Message Bus Socket.
[ OK ] Reached target sockets.target - Socket Units.
[ OK ] Reached target basic.target - Basic System.
[ OK ] Reached target sshd-keygen.target.
Starting sysstat.service - Resets System Activity Logs...
Starting systemd-homed.service - Home Area Manager...
Starting systemd-logind.service - User Login Management...
Starting dbus-broker.service - D-Bus System Message Bus...
[FAILED] Failed to start sysstat.service - Resets System Activity Logs.
See 'systemctl status sysstat.service' for details.
[ OK ] Started dbus-broker.service - D-Bus System Message Bus.
[ OK ] Started systemd-homed.service - Home Area Manager.
[ OK ] Finished systemd-homed-activate.service - Home Area Activation.
[ OK ] Started systemd-logind.service - User Login Management.
[ OK ] Started systemd-networkd.service - Network Configuration.
Starting systemd-networkd-wait-online.service - Wait for Network to be Configured...
Starting systemd-resolved.service - Network Name Resolution...
[ OK ] Started systemd-resolved.service - Network Name Resolution.
[ OK ] Reached target network.target - Network.
[ OK ] Reached target nss-lookup.target - Host and Network Name Lookups.
Starting sshd.service - OpenSSH server daemon...
Starting systemd-user-sessions.service - Permit User Sessions...
[ OK ] Finished systemd-user-sessions.service - Permit User Sessions.
[ OK ] Started console-getty.service - Console Getty.
[ OK ] Reached target getty.target - Login Prompts.
[ OK ] Started sshd.service - OpenSSH server daemon.
[ OK ] Reached target multi-user.target - Multi-User System.
[ OK ] Reached target graphical.target - Graphical Interface.
Starting systemd-update-utmp-runlevel.service - Update UTMP about System Runlevel Changes...
[ OK ] Finished systemd-update-utmp-runlevel.service - Update UTMP about System Runlevel Changes.
Fedora 35 (Rawhide Prerelease)
Kernel 5.12.12-300.fc34.x86_64 on an x86_64 (console)
rawhide login: [ OK ] Stopped session-24.scope - Session 24 of User zbyszek.
[ OK ] Removed slice system-getty.slice - Slice /system/getty.
[ OK ] Removed slice system-modprobe.slice - Slice /system/modprobe.
[ OK ] Removed slice system-sshd\x2dkeygen.slice - Slice /system/sshd-keygen.
[ OK ] Stopped target graphical.target - Graphical Interface.
[ OK ] Stopped target multi-user.target - Multi-User System.
[ OK ] Stopped target getty.target - Login Prompts.
[ OK ] Stopped target machines.target - Containers.
[ OK ] Stopped target nss-lookup.target - Host and Network Name Lookups.
[ OK ] Stopped target remote-cryptsetup.target - Remote Encrypted Volumes.
[ OK ] Stopped target timers.target - Timer Units.
[ OK ] Stopped dnf-makecache.timer - dnf makecache --timer.
[ OK ] Stopped logrotate.timer - Daily rotation of log files.
[ OK ] Stopped systemd-tmpfiles-clean.timer - Daily Cleanup of Temporary Directories.
[ OK ] Closed systemd-coredump.socket - Process Core Dump Socket.
Stopping console-getty.service - Console Getty...
Stopping dracut-shutdown.service - Restore /run/initramfs on shutdown...
Stopping sshd.service - OpenSSH server daemon...
Stopping systemd-logind.service - User Login Management...
Stopping systemd-oomd.service - Userspace Out-Of-Memory (OOM) Killer...
Stopping user@1000.service - User Manager for UID 1000...
[ OK ] Stopped systemd-oomd.service - Userspace Out-Of-Memory (OOM) Killer.
[ OK ] Stopped systemd-networkd-wait-online.service - Wait for Network to be Configured.
[ OK ] Stopped sshd.service - OpenSSH server daemon.
[ OK ] Stopped console-getty.service - Console Getty.
[ OK ] Stopped dracut-shutdown.service - Restore /run/initramfs on shutdown.
[ OK ] Stopped target sshd-keygen.target.
[ OK ] Stopped systemd-logind.service - User Login Management.
[ OK ] Stopped user@1000.service - User Manager for UID 1000.
Stopping user-runtime-dir@1000.service - User Runtime Directory /run/user/1000...
[ OK ] Unmounted run-user-1000.mount - /run/user/1000.
[ OK ] Stopped user-runtime-dir@1000.service - User Runtime Directory /run/user/1000.
[ OK ] Removed slice user-1000.slice - User Slice of UID 1000.
Stopping systemd-user-sessions.service - Permit User Sessions...
[ OK ] Stopped systemd-user-sessions.service - Permit User Sessions.
[ OK ] Stopped target network.target - Network.
[ OK ] Stopped target remote-fs.target - Remote File Systems.
Stopping systemd-homed-activate.service - Home Area Activation...
Stopping systemd-resolved.service - Network Name Resolution...
[ OK ] Stopped systemd-resolved.service - Network Name Resolution.
Stopping systemd-networkd.service - Network Configuration...
[ OK ] Stopped systemd-homed-activate.service - Home Area Activation.
Stopping systemd-homed.service - Home Area Manager...
[ OK ] Stopped systemd-homed.service - Home Area Manager.
[ OK ] Stopped target basic.target - Basic System.
[ OK ] Stopped target paths.target - Path Units.
[ OK ] Stopped target slices.target - Slice Units.
[ OK ] Removed slice user.slice - User and Session Slice.
[ OK ] Stopped target sockets.target - Socket Units.
Stopping dbus-broker.service - D-Bus System Message Bus...
[ OK ] Stopped dbus-broker.service - D-Bus System Message Bus.
[ OK ] Closed dbus.socket - D-Bus System Message Bus Socket.
[ OK ] Stopped target sysinit.target - System Initialization.
[ OK ] Stopped target cryptsetup.target - Local Encrypted Volumes.
[ OK ] Stopped systemd-ask-password-console.path - Dispatch Password Requests to Console Directory Watch.
[ OK ] Stopped systemd-ask-password-wall.path - Forward Password Requests to Wall Directory Watch.
[ OK ] Stopped target veritysetup.target - Local Verity Integrity Protected Volumes.
[ OK ] Stopped systemd-update-done.service - Update is Completed.
[ OK ] Stopped ldconfig.service - Rebuild Dynamic Linker Cache.
[ OK ] Stopped systemd-hwdb-update.service - Rebuild Hardware Database.
[ OK ] Stopped systemd-journal-catalog-update.service - Rebuild Journal Catalog.
Stopping systemd-update-utmp.service - Update UTMP about System Boot/Shutdown...
[ OK ] Stopped systemd-networkd.service - Network Configuration.
[ OK ] Closed systemd-networkd.socket - Network Service Netlink Socket.
[ OK ] Stopped systemd-sysctl.service - Apply Kernel Variables.
[ OK ] Stopped systemd-update-utmp.service - Update UTMP about System Boot/Shutdown.
[ OK ] Stopped systemd-tmpfiles-setup.service - Create Volatile Files and Directories.
[ OK ] Stopped target local-fs.target - Local File Systems.
Unmounting home.mount - /home...
Unmounting run-credentials-systemd\x2dsysusers.se…e.mount - /run/credentials/systemd-sysusers.service...
Unmounting tmp.mount - Temporary Directory /tmp...
[ OK ] Unmounted home.mount - /home.
[ OK ] Unmounted tmp.mount - Temporary Directory /tmp.
[ OK ] Unmounted run-credentials-systemd\x2dsysusers.service.mount - /run/credentials/systemd-sysusers.service.
[ OK ] Stopped target local-fs-pre.target - Preparation for Local File Systems.
[ OK ] Stopped target swap.target - Swaps.
[ OK ] Reached target umount.target - Unmount All Filesystems.
[ OK ] Stopped systemd-tmpfiles-setup-dev.service - Create Static Device Nodes in /dev.
[ OK ] Stopped systemd-sysusers.service - Create System Users.
[ OK ] Stopped systemd-remount-fs.service - Remount Root and Kernel File Systems.
[ OK ] Reached target shutdown.target - System Shutdown.
[ OK ] Reached target final.target - Late Boot Services.
[ OK ] Finished systemd-poweroff.service - System Power Off.
[ OK ] Reached target poweroff.target - System Power Off.
Sending SIGTERM to remaining processes...
Sending SIGKILL to remaining processes...
All filesystems, swaps, loop devices, MD devices and DM devices detached.
Powering off.
We would always call path_simplify() before doing a lookup, which requires the
path key to be duplicated first. But the hashmap lookup doesn't require this…
So let's opportunistically skip the allocation if the key is already present.
Inspired by https://github.com/systemd/systemd/pull/19973.
Show message "Deactivated successfully" in debug mode (when manager is
user) rather than in info mode. This message has low information value
for regular users and it might be a bit overwhelming on a system with
a lot of devices.
All unit types can be serialized. This function was really checking whether the
unit type has custom serialization/deserialization code. But we don't need a
function for this.
Also, the check that both .serialize() and .deserialize_item() are defined is
better written as an assert. Not we have a function which would skip
serialization/deserializaton for the unit if we forgot to set either of the
fields.
These are so many runtime objects, let's add a bpf_firewall_close()
helper that destroys them all, and call that from unit_free(), simply as
an excercise of encapsulating more BPF code in bpf-firewall.c.
This also brings the destruction order and variable declaration order in
struct Unit into the same systematic order.
No change in behaviour just some minor refactoring.
This moves all calls that shall do deferred work on detecting whether to
start/stop the unit or dependent units after a unit state change to the
end of the function, to make things easier to read.
So far, these calls were spread all over the function, and
conditionalized needlessly on MANAGER_RELOADING(). This is unnecessary,
since the queues are not dispatched while reloading anyway, and
immediately before acting on a queued unit we'll check if the suggested
operation really makes sense.
The only conditionalizaiton we leave in is on checking the new unit
state itself, since we have that in a local variable anyway.
So far StopWhenUnneeded= handling and UpheldBy= handling was already
processed by a queue that is dispatched in a deferred mode of operation
instead of instantly. This changes BoundBy= handling to be processed the
same way.
This should ensure that all *event*-to-job propagation is done directly
from unit_notify(), while all *state*-to-job propagation is done from a
deferred work queue, quite systematically. The work queue is submitted
to by unit_notify() too.
Key really is the difference between event and state: some jobs shall be
queued one-time on events (think: OnFailure= + OnSuccess= and similar),
others shall be queued continuously when a specific state is in effect
(think: UpheldBy=). The latter cases are usually effect of the
combination of states of a few units (e.g. StopWhenUnneeded= checks
wether any of the Wants=/Requires=/… deps are still up before acting),
and hence it makes sense to trigger them to be run after an individual
unit's state changed, but process them on a queue that runs whenever
there's nothing else to do that ensures the decision on them is only
taken after all jobs/queued IO events are dispatched, and things
settled, so that it makes sense to come to a combined conclusion. If
we'd dispatch this work immediately inside of unit_notify() we'd always
act instantly, even though another event from another unit that is
already queued might make the work unnecessary or invalid.
This is mostly a commit to make things philosophically clean. It does
not add features, but it should make corner cases more robust.
Let's not consider a unit unneeded while it is reloading.
Uneeded should be a pretty weak concept: if there's any doubt that
something bit be needed, then assume it is.
This is like a really strong version of Wants=, that keeps starting the
specified unit if it is ever found inactive.
This is an alternative to Restart= inside a unit, acknowledging the fact
that whether to keep restarting the unit is sometimes not a property of
the unit itself but the state of the system.
This implements a part of what #4263 requests. i.e. there's no
distinction between "always" and "opportunistic". We just dumbly
implement "always" and become active whenever we see no job queued for
an inactive unit that is supposed to be upheld.
This is similar to OnFailure= but is activated whenever a unit returns
into inactive state successfully.
I was always afraid of adding this, since it effectively allows building
loops and makes our engine Turing complete, but it pretty much already
was it was just hidden.
Given that we have per-unit ratelimits as well as an event loop global
ratelimit I feel safe to add this finally, given it actually is useful.
Fixes: #13386
This takes inspiration from PropagatesReloadTo=, but propagates
stop jobs instead of restart jobs.
This is defined based on exactly two atoms: UNIT_ATOM_PROPAGATE_STOP +
UNIT_ATOM_RETROACTIVE_STOP_ON_STOP. The former ensures that when the
unit the dependency is originating from is stopped based on user
request, we'll propagate the stop job to the target unit, too. In
addition, when the originating unit suddenly stops from external causes
the stopping is propagated too. Note that this does *not* include the
UNIT_ATOM_CANNOT_BE_ACTIVE_WITHOUT atom (which is used by BoundBy=),
i.e. this dependency is purely about propagating "edges" and not
"levels", i.e. it's about propagating specific events, instead of
continious states.
This is supposed to be useful for dependencies between .mount units and
their backing .device units. So far we either placed a BindsTo= or
Requires= dependency between them. The former gave a very clear binding
of the to units together, however was problematic if users establish
mounnts manually with different block device sources than our
configuration defines, as we there might come to the conclusion that the
backing device was absent and thus we need to umount again what the user
mounted. By combining Requires= with the new StopPropagatedFrom= (i.e.
the inverse PropagateStopTo=) we can get behaviour that matches BindsTo=
in every single atom but one: UNIT_ATOM_CANNOT_BE_ACTIVE_WITHOUT is
absent, and hence the level-triggered logic doesn't apply.
Replaces: #11340
Let's add an implicit reverse dep OnFailureOf=. This is exposed via the
bus to make things more debuggable: you can now ask systemd for which
units a specific unit is the failure handler.
OnFailure= was the only dependency type that had no inverse, this fixes
that.
Now that deps are a bit cheaper, it should be OK to add deps that only
serve debug purposes.
The slice a unit is assigned to is currently a UnitRef reference. Let's
turn it into a proper dependency, to simplify and clean up code a bit.
Now that new dep types are cheaper, deps should generally be preferable
over everything else, if the concept applies.
This brings one major benefit: we often have to iterate through all unit
a slice contains. So far we iterated through all Before= dependencies of
the slice unit to achieve that, filtering out unrelated units, and
taking benefit of the fact that slice units are implicitly ordered
Before= the units they contain. By making Slice= a proper dependency,
and having an accompanying SliceOf= dependency type, this is much
simpler and nicer as we can directly enumerate the units a slice
contains.
The forward dependency is actually called InSlice internally, since we
already used the UNIT_SLICE name as UnitType field. However, since we
don't intend to expose the dependency to users as dep anyway (we already
have the regular Slice D-Bus property for this) this shouldn't matter.
The SliceOf= implicit dependency type (the erverse of Slice=/InSlice=)
is exported over the bus, to make things a bit nicer to debug and
discoverable.
In a later commit we intend to move the slice logic to use proper
dependencies instead of a "UnitRef" object. This preparatory commit
drops direct use of the slice UnitRef object for a static inline
function UNIT_GET_SLICE() that is both easier to grok, and allows us to
easily replace its internal implementation later on.
We recently started making more use of malloc_usable_size() and rely on
it (see the string_erase() story). Given that we don't really support
sytems where malloc_usable_size() cannot be trusted beyond statistics
anyway, let's go fully in and rework GREEDY_REALLOC() on top of it:
instead of passing around and maintaining the currenly allocated size
everywhere, let's just derive it automatically from
malloc_usable_size().
I am mostly after this for the simplicity this brings. It also brings
minor efficiency improvements I guess, but things become so much nicer
to look at if we can avoid these allocation size variables everywhere.
Note that the malloc_usable_size() man page says relying on it wasn't
"good programming practice", but I think it does this for reasons that
don't apply here: the greedy realloc logic specifically doesn't rely on
the returned extra size, beyond the fact that it is equal or larger than
what was requested.
(This commit was supposed to be a quick patch btw, but apparently we use
the greedy realloc stuff quite a bit across the codebase, so this ends
up touching *a*lot* of code.)
This mirrors the change done for systemd-resolved in
9793530228. Quoting that patch:
> We generally operate on the assumption that a source is "gone" as soon as we
> unref it. This is generally true because we have the only reference. But if
> something else holds the reference, our unref doesn't really stop the source
> and it could fire again.
In particular, we take temporary references from sd-event code, and when called
from an sd-event callback, we could temporarily see this elevated reference
count. This patch doesn't seem to change anything, but I think it's nicer to do
the same change as in other places and not rely on _unref() immediately
disabling the source.
This commit applies the filtering imposed by LogLevelMax on a unit's
processes to messages logged by PID1 about the unit as well.
The target use case for this feature is a service that runs on a timer
many times an hour, where the system administrator decides that writing
a generic success message to the journal every few minutes or seconds
adds no diagnostic value and isn't worth the clutter or disk I/O.
Add supported and install unit interface for socket-bind feature.
supported verifies that
- unified cgroup hierarchy (cgroup v2) is used
- BPF_FRAMEWORK (libbpf + clang + llvm + bpftool) was available in
compile time
- kernel supports BPF_PROG_TYPE_CGROUP_SOCK_ADDR
- bpf programs can be loaded into kernel
- bpf link can be used
install:
- load bpf_object from bpf skeleton
- resize rules map to fit socket_bind_allow and socket_bind deny rules
from cgroup context
- populate cgroup-bpf maps with rules
- get bpf programs from bpf skeleton
- attach programs to unit cgroup using bpf link
- save bpf link in the unit
With some versions of the compiler, the _cleanup_ attr makes it think
the variable might be freed/closed when uninitialized, even though it
cannot happen. The added cost is small enough to be worth the benefit,
and optimized builds will help reduce it even further.
- Introduce support of cgroup-bpf programs managed (i.e. compiled,
loaded to and unloaded from kernel) externally. Systemd is only
responsible for attaching programs to unit cgroup hence the name
'foreign'.
Foreign BPF programs are identified by bpf program ID and attach type.
systemd:
- Gets kernel FD of BPF program;
- Makes a unique identifier of BPF program from BPF attach type and
program ID. Same program IDs mean the same program, i.e the same
chunk of kernel memory. Even if the same program is passed multiple
times, identical (program_id, attach_type) instances are collapsed
into one;
- Attaches programs to unit cgroup.
Clean up ignore_signals() + default_signals() + sigaction_many() a bit:
make it unnecessary to explicitly terminate the signal list with -1.
Merge all three calls into a single function that is just called with
slightly different parameters. And eliminate an unnecessary extra
iteration in its inner for() loop.
No change in behaviour.
I started working on this because I wanted to change how
DEFINE_TRIVIAL_CLEANUP_FUNC is defined. Even independently of that change, it's
nice to make make things more consistent and predictable.
The property is never set by systemd, only reset after a stop or restart or
reload. It may externally be set to mark the unit for a later restart/reload.
I wasn't sure whether to configure the property only for the types where this
makes sense (Service, Swap, etc). But Restart() method is defined on the unit,
and also having this always under the same property name is more convenient.
Geass-LL
Maanya Goenka
Lennart Poettering
Michal Koutný
Dan Streetman
Yu Watanabe
Zbigniew Jędrzejewski-Szmek
Jan Macku
Franck Bui
Ryan Hendrickson
Julia Kartseva
Luca Boccassi