This adds minimal hardware watchdog support to PID 1. The idea is that
PID 1 supervises and watchdogs system services, while the hardware
watchdog is used to supervise PID 1.
This adds two hardware watchdog configuration options, for the runtime
watchdog and for a shutdown watchdog. The former is active during normal
operation, the latter only at reboots to ensure that if a clean reboot
times out we reboot nonetheless.
If the runtime watchdog is enabled PID 1 will automatically wake up at
half the configured interval and write to the watchdog daemon.
By default we enable the shutdown watchdog, but leave the runtime
watchdog disabled in order not to break independent hardware watchdog
daemons people might be using.
This is only the most basic hookup. If necessary we can later on hook
up the watchdog ping more closely with services deemed crucial.
It is easier to see what job_type_merge() is doing when the merging
rules are written in the form of a table.
job_type_is_superset() contained redundant information. It can be
simplified to a simple rule: Type A is a superset of B iff merging A
with B gives A.
Two job types are conflicting iff they are not mergeable.
Make job_type_lookup_merge() the core function to decide the type
merging. All other job_type_*() are just short wrappers around it.
They can be inline.
test-job-type gives the same results as before.
btw, the systemd binary is smaller by almost 1 KB.
Especially in the case of --enable-split-usr, several units will point
to the wrong location for systemctl. Use @SYSTEMCTL@ which will always
contain the proper path.
Many programming languages don't allow variable names beginning in dots,
hence let's use double underscores for the location fields instead. This
gets us the simple rule:
__ is the prefix for location fields (i.e. fields that are used to
identify entries, rather than part of the entries)
_ is the prefix for trusted fields (i.e. those fields journald itself
adds to all entries)
no prefix for unrusted fields (i.e. all fields normal client code sends
us)
This reverts commit 9586cdfab6.
(but not the TODO hunk).
The bug was already fixed by 1a710b43. And if other errors occur, we
don't want to leave the socket active in order to avoid having socket
tarpits.
This logic can be turned off by defining SD_JOURNAL_SUPPRESS_LOCATION
before including sd-journal.h.
This also saves/restores errno in all logging functions, in order to be
useful as logging calls without side-effects.
This also adds a couple of __unlikely__ around the early checks in the
logging calls, in order to minimize the runtime impact.
Suppose that foo.service/start is a job waiting on other job bar.service/start
to finish. And then foo.service/restart is enqueued (not using
--ignore-dependencies).
Currently this makes foo.service start immediately, forgetting about the
ordering to bar.service.
The runnability check for JOB_RESTART jobs looks only at dependencies for
stopping. That's actually correct, because restart jobs should be treated the
same as stop jobs at first. The bug is that job_run_and_invalidate() does not
treat them exactly the same as stop jobs. unit_start() gets called without
checking for the runnability of the converted JOB_START job.
The fix is to simplify the switch in job_run_and_invalidate(). Handle
JOB_RESTART identically to JOB_STOP.
Also simplify the handling of JOB_TRY_RESTART - just convert it to JOB_RESTART
if the unit is active and let it fall through to the JOB_RESTART case.
Similarly for JOB_RELOAD_OR_START - have a fall through to JOB_START.
In job_finish_and_invalidate() it's not necessary to check for JOB_TRY_RESTART
with JOB_DONE, because JOB_TRY_RESTART jobs will have been converted to
JOB_RESTART already.
Speeding up the restart of services in "auto-restart" state still works as
before.
Improves: https://bugzilla.redhat.com/show_bug.cgi?id=753586
but it's still not perfect. With this fix the try-restart action will wait for
the restart to complete in the right order, but the optimal behaviour would be
to finish quickly (without disturbing the start job).
If we try to locate a monotonic time in a file that doesn't have any
entries with the matching boot id, then don't fail on it, simply
fall back to calendar time.
The default setups should be a stateless as possible. /tmp as tmpfs is
the intended default for general purpose systems.
Small temporary files should not be stored on disk; lager files, or
files which should potentially survive a reboot, belong into /var/tmp.
Also catch up with some good old UNIX history.
More details are here:
https://fedoraproject.org/wiki/Features/tmp-on-tmpfs
Since a number of distribitions don't need this compat glue anymore drop
it from systemd upstream. Distributions which still haven't converted
to /run can steal these unit files from the git history if they need to.
udisks2 doesn't use /media anymore, instead mounts removable media in a
user-private directory beneath /run. /media is hence mostly obsolete and
hence it makes little sense to continue to mount a tmpfs to it.
Distributions should consider dropping the mount point entirely since
nothing uses it anymore.
Kay Sievers