Remove the list logic, and simply skip passing metadata if more than one
unit triggered an OnFailure/OnSuccess handler.
Instead of a single env var to loop over, provide each separate item
as its own variable.
Fixes https://github.com/systemd/systemd/issues/22370
When a service exits and triggers either an OnFailure= or OnSuccess=
dependency we now set a new environment variable for the ExecStart= and
ExecStartPre= process. This variable $MONITOR_METADATA exposes the
metadata relating to the service which triggered the dependency.
MONITOR_METADATA takes the following form:
MONITOR_METADATA="SERVICE_RESULT=<result-string0>,EXIT_CODE=<exit-code0>,EXIT_STATUS=<exit-status0>,INVOCATION_ID=<id>,UNIT=<triggering-unit0.service>;SERVICE_RESULT=<result-stringN>,EXIT_CODE=<exit-codeN>,=EXIT_STATUS=<exit-statusN>,INVOCATION_ID=<id>,UNIT=<triggering-unitN.service>"
MONITOR_METADATA is space separated set of metadata relating to the
service(s) which triggered the dependency. This is a list since if we
have 2 services which trigger the same dependency then the dependency
start job may be merged. In this case we need to pass both service
metadata to the triggered service. If there is no job merging then
MONITOR_METADATA will be a single entry.
For example, in the case we had a service "failer.service" which
triggers "failer-handler.service", the following variable is exported to
the ExecStart= and ExecStartPre= processes in failer-handler.service:
MONITOR_METADATA="SERVICE_RESULT=exit-code,EXIT_CODE=exited,EXIT_STATUS=1,INVOCATION_ID=67c657ed7b34466ea369abdf994c6393,UNIT=failer.service"
In another example where we have failer.service and failer2.service
which both also trigger failer-handler.service then the start job for
failer-handler.service may be merged and we might get the following:
MONITOR_METADATA="SERVICE_RESULT=exit-code,EXIT_CODE=exited,EXIT_STATUS=1,INVOCATION_ID=16a93ad196c94109990fb8b9aa5eef5f,UNIT=failer.service;SERVICE_RESULT=exit-code,EXIT_CODE=exited,EXIT_STATUS=1,INVOCATION_ID=ff70131e4cc145e994fb621de25a3e8f,UNIT=failer2.service"
Up until now the main reason why we didn't proceed with starting the
unit was exceed start limit burst. However, for unit types like mounts
the other reason could be effective ratelimit on /proc/self/mountinfo
event source. That means our mount unit state may not reflect current
kernel state. Hence, we need to attempt to re-run the start job again
after ratelimit on event source expires.
As we will be introducing another reason than start limit let's rename
the virtual function that implements the check.
Defines a "UNIT_DEPENDENCY_SLICE_PROPERTY" UnitDependencyMask type that
is used when adding slices to the dependencies hashmap. This type is
used to remove slice dependencies when they get overridden by new ones.
Fixes#20182
Alternative to https://github.com/systemd/systemd/pull/20531.
Whenever a service triggered by another unit fails condition checks,
stop the triggering unit to prevent systemd busy looping trying to
start the triggered unit.
This adds 6 functions to implement RestrictFileSystems=
* lsm_bpf_supported() checks if LSM BPF is supported. It checks that
cgroupv2 is used, that BPF LSM is enabled, and tries to load the BPF
LSM program which makes sure BTF and hash of maps are supported, and
BPF LSM programs can be loaded.
* lsm_bpf_setup() loads and attaches the LSM BPF program.
* lsm_bpf_unit_restrict_filesystems() populates the hash of maps BPF map with the
cgroupID and the set of allowed or denied filesystems.
* lsm_bpf_cleanup() removes a cgroupID entry from the hash of maps.
* lsm_bpf_map_restrict_fs_fd() is a helper function to get the file
descriptor of the BPF map.
* lsm_bpf_destroy() is a wrapper around the destroy function of the BPF
skeleton file.
Previously, if a unit file which contains n IPAddressAllow/Deny= lines,
then the computational order of parsing the file was O(n^3), as
ip_address_access_reduce(), whose order is O(n^2), is called for each line.
By replacing in_addr_prefix related functions, now the computational
order is O(n log n).
Fixes#20680.
When a job is skipped, it's useful to know exactly which condition failed so
let's add this information to the error message.
To avoid having to dynamically generate a format string, we special case the
formatting of condition failed messages.
Fixes#17433. Currently, if any of the validations we do before we
check start rate limiting fail, we can still enter a busy loop as
no rate limiting gets applied. A common occurence of this scenario
is path units triggering a service that fails a condition check.
To fix the issue, we simply move up start rate limiting checks to
be the first thing we do when starting a unit. To achieve this,
we add a new method to the unit vtable and implement it for the
relevant unit types so that we can do the start rate limit checks
earlier on.
This commit introduces all the logic to load and attach the BPF
programs to restrict network interfaces when a unit specifying it is
loaded.
Signed-off-by: Mauricio Vásquez <mauricio@kinvolk.io>
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.
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.
When e.g. tmp.mount is present in the initrd, and we serialize it, switch root,
and deserialize, the new systemd is confused because it thinks /tmp is mounted.
In general, it doesn't make sense to serialize anything that refers to paths in
the old root file system.
This fixes two errors for me:
1. tmp.mount was not mounted properly before local-fs.target. It would be
mounted as some point (I guess when we re-read /proc/self/mountinfo for some
other reason). In effect systemd-tmpfiles-setup.service would see one fs, and
some other units started later a different one. In particular gdm.service would
fail because the pre-created /tmp/.X11-unix with proper permissions would not
exist at time it was started.
2. # systemd[1]: proc-sys-fs-binfmt_misc.automount: Got hangup/error on autofs pipe from kernel. Likely our automount point has been unmounted by someone or something else?
# systemd[1]: proc-sys-fs-binfmt_misc.automount: Failed with result 'unmounted'.
# systemd[1]: Mounting proc-sys-fs-binfmt_misc.mount...
# systemd[1]: Mounted proc-sys-fs-binfmt_misc.mount.
# systemd[1]: Starting systemd-binfmt.service...
# systemd[1]: Finished systemd-binfmt.service.
# systemd[1]: proc-sys-fs-binfmt_misc.automount: Path /proc/sys/fs/binfmt_misc is already a mount point, refusing start.
# systemd[1]: Failed to set up automount proc-sys-fs-binfmt_misc.automount.
# systemd[1]: proc-sys-fs-binfmt_misc.automount: Path /proc/sys/fs/binfmt_misc is already a mount point, refusing start.
# systemd[1]: Failed to set up automount proc-sys-fs-binfmt_misc.automount.
# systemd[1]: proc-sys-fs-binfmt_misc.automount: Path /proc/sys/fs/binfmt_misc is already a mount point, refusing start.
# systemd[1]: Failed to set up automount proc-sys-fs-binfmt_misc.automount.
# systemd[1]: Stopping systemd-binfmt.service...
# systemd[1]: systemd-binfmt.service: Deactivated successfully.
# systemd[1]: Stopped systemd-binfmt.service.
I couldn't understand the error here, but in retrospect the first line is entirely
correct: "someone or something else" was the old systemd unmounting the old root.
The usual: bitfields make sense as a memory-saving measure when we have many
objects of a given type. When the object appears at most in a few copies, the
overhead of additional code to access bitfields is more than the savings.
unit_serialize_item() was dropped in d68c645bd3.
But "cannot be restored from other sources" is also not entirely true: for
example for mounts we may be able to figure out most state from /p/s/mountinfo.
So let's make the comment more oblique.
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.
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
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.
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
- 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.
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.
We had a lone 'bool job_running_timeout_set:1', which generated a hole. Let's
move things around a bit. The structure is a tiny bit smaller and has less
holes:
/* size: 1192, cachelines: 19, members: 149 */
/* sum members: 1175, holes: 3, sum holes: 11 */
/* sum bitfield members: 27 bits, bit holes: 1, sum bit holes: 7 bits */
/* bit_padding: 14 bits */
/* last cacheline: 40 bytes */
/* size: 1184, cachelines: 19, members: 149 */
/* sum members: 1175, holes: 1, sum holes: 4 */
/* sum bitfield members: 27 bits (3 bytes) */
/* bit_padding: 13 bits */
/* last cacheline: 32 bytes */
As suggested in https://github.com/systemd/systemd/pull/11484#issuecomment-775288617.
This does not touch anything exposed in src/systemd. Changing the defines there
would be a compatibility break.
Note that tests are broken after this commit. They will be fixed in the next one.
Update ExecCondition= to set Unit->condition_result and return JOB_DONE
in the Job results if the check fails so as to match the current behavior
of ConditionXYZ= w.r.t units/jobs dependency checks.
Fixes: #18207
In 4c2ef32767 we enabled propagating
triggered unit state to the triggering unit for service units in more
load states, so that we don't accidentally stop tracking state
correctly.
Do the same for our other triggering unit states: automounts, paths, and
timers.
Also, make this an assertion rather than a simple test. After all it
should never happen that we get called for half-loaded units or units of
the wrong type. The load routines should already have made this
impossible.
Instead of assuming that more-recently modified directories have higher mtime,
just look for any mtime changes, up or down. Since we don't want to remember
individual mtimes, hash them to obtain a single value.
This should help us behave properly in the case when the time jumps backwards
during boot: various files might have mtimes that in the future, but we won't
care. This fixes the following scenario:
We have /etc/systemd/system with T1. T1 is initially far in the past.
We have /run/systemd/generator with time T2.
The time is adjusted backwards, so T2 will be always in the future for a while.
Now the user writes new files to /etc/systemd/system, and T1 is updated to T1'.
Nevertheless, T1 < T1' << T2.
We would consider our cache to be up-to-date, falsely.
We really only care if the cache has been reloaded between the time when we
last attempted to load this unit and now. So instead of recording the actual
time we try to load the unit, just store the timestamp of the cache. This has
the advantage that we'll notice if the cache mtime jumps forward or backward.
Also rename fragment_loadtime to fragment_not_found_time. It only gets set when
we failed to load the unit and the old name was suggesting it is always set.
In https://bugzilla.redhat.com/show_bug.cgi?id=1871327
(and most likely https://bugzilla.redhat.com/show_bug.cgi?id=1867930
and most likely https://bugzilla.redhat.com/show_bug.cgi?id=1872068) we try
to load a non-existent unit over and over from transaction_add_job_and_dependencies().
My understanding is that the clock was in the future during inital boot,
so cache_mtime is always in the future (since we don't touch the fs after initial boot),
so no matter how many times we try to load the unit and set
fragment_loadtime / fragment_not_found_time, it is always higher than cache_mtime,
so manager_unit_cache_should_retry_load() always returns true.
When the system is under heavy load, it can happen that the unit cache
is refreshed for an unrelated reason (in the test I simulate this by
attempting to start a non-existing unit). The new unit is found and
accounted for in the cache, but it's ignored since we are loading
something else.
When we actually look for it, by attempting to start it, the cache is
up to date so no refresh happens, and starting fails although we have
it loaded in the cache.
When the unit state is set to UNIT_NOT_FOUND, mark the timestamp in
u->fragment_loadtime. Then when attempting to load again we can check
both if the cache itself needs a refresh, OR if it was refreshed AFTER
the last failed attempt that resulted in the state being
UNIT_NOT_FOUND.
Update the test so that this issue reproduces more often.
We allocated the names set for each unit, but in the majority of cases, we'd
put only one name in the set:
$ systemctl show --value -p Names '*'|grep .|grep -v ' '|wc -l
564
$ systemctl show --value -p Names '*'|grep .|grep ' '|wc -l
16
So let's add a separate .id field, and only store aliases in the set, and only
create the set if there's at least one alias. This requires a bit of gymnastics
in the code, but I think this optimization is worth the trouble, because we
save one object for many loaded units.
In particular set_complete_move() wasn't very useful because the target
unit would always have at least one name defined, i.e. the optimization to
move the whole set over would never fire.
Luca Boccassi
Yu Watanabe
Daan De Meyer
Peter Morrow
Michal Sekletar
Anita Zhang
Iago Lopez Galeiras
Mauricio Vásquez
Zbigniew Jędrzejewski-Szmek
Lennart Poettering
Ryan Hendrickson
Julia Kartseva
Luca Boccassi