There is no way to ignore an event these days. Libudev events can
not be suppressed. It only prevents RUN keys from being executed,
which results in an inconsistent behavior in current setups.
External programs triggered by events (via RUN=) will inherit udev's
signal mask, which is set to block all but SIGALRM. For most utilities,
this is OK, but if we start daemons from RUN=, we run into trouble
(especially as SIGCHLD is blocked).
This change saves the original sigmask when udev starts, and restores it
just before we exec() the external command.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Event processes now get re-used after they handled an event. This reduces
pressure on the CPU significantly because cloned event processes no longer
cause page faults in the main daemon. After the events have settled, the
no longer needed worker processes get killed.
<Keybuk> kay: udev git head ftbfs
<Keybuk> udev-watch.o: In function `udev_selinux_init':
<Keybuk> /../udev/udev.h:130: multiple definition of `udev_selinux_init'
This allows you to re-process the rules if the content of the device
has been changed, most useful for block subsystem to cause vol_id to
be run again.
Since a while we change the database with a "test" run, but do not update
the node and symlinks. We need to "force" all the time, to keep things
in sync.
The in-memory rule array of a common desktop distro install took:
1151088 bytes
with the token list:
109232 bytes tokens (6827 * 16 bytes), 71302 bytes buffer
"Hello world!" linked against libselinux parses /proc/mounts and
whatever else on startup, even when the lib is not needed at all.
Not funny! Get rid of that thing where it's not absolutely needed.
envp is not standardized, and may become invalid when environment variables
are modified. Since udev never actually uses it, we can simply remove it.
Should anyone miss it in future, they can use the standardized environ
variable - like udev_rules.c does already.
