Similarly to "setup" vs. "set up", "fallback" is a noun, and "fall back"
is the verb. (This is pretty clear when we construct a sentence in the
present continous: "we are falling back" not "we are fallbacking").
This adds support for user to set & get reboot parameter for reboot.
As callee would be next issuing Reboot call same policy checks are being used.
If unit file issuing the reboot action defines RebootArgument (or similar) that
setting takes precedence.
Commit d85515edcf changed logic how reboot is
executed. That commit changed behavior to use emergency action reboot code path
to perform the reboot.
This inadvertently broke rebooting with argument:
$ systemctl reboot custom-reason
Restore original behavior so that if reboot service unit similar to
systemd-reboot.service is executed it is possible to override reboot reason
with "systemctl reboot ARG".
When "systemctl reboot ARG" is executed ARG is placed in file
/run/systemd/reboot-param and reboot is issued using logind's Reboot
dbus-service.
If RebootArgument is specified in systemd-reboot.service it takes precedence
over what systemctl sets.
Fixes: #11828
This doesn't have much effect on the final build, because we link libbasic.a
into libsystemd-shared.so, so in the end, all the object built from basic/
end up in libsystemd-shared. And when the static library is linked into binaries,
any objects that are included in it but are not used are trimmed. Hence, the
size of output artifacts doesn't change:
$ du -sb /var/tmp/inst*
54181861 /var/tmp/inst1 (old)
54207441 /var/tmp/inst1s (old split-usr)
54182477 /var/tmp/inst2 (new)
54208041 /var/tmp/inst2s (new split-usr)
(The negligible change in size is because libsystemd-shared.so is bigger
by a few hundred bytes. I guess it's because symbols are named differently
or something like that.)
The effect is on the build process, in particular partial builds. This change
effectively moves the requirements on some build steps toward the leaves of the
dependency tree. Two effects:
- when building items that do not depend on libsystemd-shared, we
build less stuff for libbasic.a (which wouldn't be used anyway,
so it's a net win).
- when building items that do depend on libshared, we reduce libbasic.a as a
synchronization point, possibly allowing better parallelism.
Method:
1. copy list of .h files from src/basic/meson.build to /tmp/basic
2. $ for i in $(grep '.h$' /tmp/basic); do echo $i; git --no-pager grep "include \"$i\"" src/basic/ 'src/lib*' 'src/nss-*' 'src/journal/sd-journal.c' |grep -v "${i%.h}.c";echo ;done | less
Zbigniew Jędrzejewski-Szmek