This removes the call to log_close(), and refactors how fork() is done. Now
the parent also goes through normal cleanup. This isn't necessary to use the
macro, but it feels cleaner this way.
My logs are full of:
systemd-udevd[6586]: seq 13515 queued, 'add' 'block'
systemd-udevd[6586]: seq 13516 queued, 'change' 'block'
systemd-udevd[6586]: seq 13517 queued, 'change' 'block'
systemd-udevd[6586]: seq 13518 queued, 'remove' 'bdi'
systemd-udevd[6586]: seq 13519 queued, 'remove' 'block'
systemd-udevd[9865]: seq 13514 processed
systemd-udevd[9865]: seq 13515 running
systemd-udevd[9865]: GROUP 6 /usr/lib/udev/rules.d/50-udev-default.rules:59
systemd-udevd[9865]: IMPORT builtin 'blkid' /usr/lib/udev/rules.d/60-persistent-storage.rules:95
systemd-udevd[9865]: IMPORT builtin 'blkid' fails: No such file or directory
systemd-udevd[9865]: loop4: Failed to add device '/dev/loop4' to watch: No such file or directory
(the last line is at error level).
If we are too slow to set up a watch and the device is already gone by the time
we try, this is not an error.
Rebooting to set change the kernel command line to set some udev parameters is
inconvenient. Let's allow setting more stuff in the config file.
Also drop quotes from around "info" in udev.conf. We need to accept them for
compatibility, but there is no reason to use them.
It was always set to one third of timeout_usec, so let's simplify things by
calculating it using a helper function right before it is used.
Before 9d9264ba39, udevd.c would avoid setting
timeout_warn_usec to 0, using 1 instead. This wasn't necessary, because when
timeout_warn_usec is finally used in spawn_wait(), it is ignored if
timeout_usec is 0 or timeout_warn_usec is 0. So there was no need to handle
this case specially.
The function util_log_priority() is almost same as
log_level_from_string(). The difference between them is only that
util_log_priority() accepts such that '3 hogehoge'.
The uevent handling in udevd is not cpu hungry.
So, let's increase the default number of workers per cpu.
This decrease the number of queued uevents.
Without this commit (children_max is 16 on my laptop)
```
$ journalctl -b -u systemd-udevd.service | grep reached | wc -l
1544
```
With this commit (children_max is 30 on my laptop)
```
$ journalctl -b -u systemd-udevd.service | grep reached | wc -l
7
```
During boot process, many worker processes are forked and killed.
To decrease cycles of forking and killing worker, let's wait
3 seconds before killing workers. If new uevent or inotify event
comes within the delay, the killing porcess will be cancelled.
Zbigniew Jędrzejewski-Szmek