Possible race conditions (they all happen between the check of existence
of a topic and trying to create the node):
- single instance, with multiple advertisers during the first advertise:
both advertisers see the topic as non-existent and try to advertise it.
One of them will fail, leading to an error message.
This is the cause for telemetry_status advert failure seen in SITL in
rare cases.
- multi-instance: subscription to non-existing instance -> px4_open fails,
and the subscriber tries to create the node. If during that time a
publisher publishes that instance, the subscriber will get (instance+1)
(or fails if the max number of instances is exceeded).
This is a race that goes pretty much unnoticed.
- multi-instance: 2 publishers can get the same instance (if is_published()
is false in case both have not published data yet).
This can also go unnoticed.
Therefore the patch changes where _advertised is set: it is now set
directly during the advertisement instead of during publication.
This issue was found by @khabir and reported over slack.
It resulted from the split up of the big pr #12072 into #13262.
I took over the interface while the internal states still stayed the
hard to understand internal ones. One of the follow up refactors will
fix this completely and the entire legacy setpoint restore block can
be removed.
* FW attitude controller, FW position controller and VTOL attitude controller subscribe to airspeed_validated topic
* add possibility to switch off the airspeed valid checks
* remove airspeed valid checks from commander
* clean up of VTOL transition logic
* Airspeed Selector: remove dynamic allocation of airspeed validators (depending on number of connected sensors) but do it statically for the maximum number allowed. Check for number of connected sensors not only during start up, but always when vehicle is disarmed.
* Airspeed Selector: change work queue from lp to att_pos_ctrl as this module is safety-critical
* add airspeed selector to px4_fmu-v2 defaults
* fix formatting
* RoverPositionControl: Support Actuator Control Setpoints (fixes#13192)
* RoverPositonControl: remove control modes, that aren't currently implemented
* RoverPositionControl: use new Publication API
When running in HITL mode, pwm_out_sim publishes actuator_outputs.
px4io unconditionally publishes the uOrb actuator_outputs. When HITL
is configured, the px4io copy of the uOrb has all zeros.
The result is that there are two publications, one valid, and one
all-zeros. This causes the HIL_ACTUATOR_CONTROLS mavlink message
to be incorrect (all-zeros) and the SERVO_OUTPUTS_RAW mavlink
message to be inconsistent, as it takes the data from one or the
other uOrb randomly each cycle.
The fix is to let px4io know that HITL is in effect when it is
started, and modify px4io to suppress publication in this case.
This is a bigger more complicated fix than I would like, but I
think it is conceptually correct.
Signed-off-by: Nik Langrind <langrind@gmail.com>
Beat Küng