perf(hesai): remove decoder thread and MtQueue, make everything single-threaded

[mojomex]

PR Type

• Improvement

Related Links

• feat(hesai_hw_interface): configure and check SO_RCVBUF automatically #186 -- PR that allows for longer periods between packet polls

Description

This PR removes the thread-safe queue (MtQueue) from HesaiRosWrapper and gets rid of the decoder thread. This can be done because of #186, which ensures that up to 1 scan's worth of packets can be buffered in the UDP socket to allow for less frequent polling for new packets. This means that the decoder thread's work can be done in the hardware interface thread, too, reducing scheduling and locking overhead.

Remarks

Needs stress-testing, e.g. on the bus reference design.

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[codecov]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Project coverage is 0.00%. Comparing base (3284357) to head (daf3b93).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
nebula_ros/src/hesai/hesai_ros_wrapper.cpp	0.00%	2 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (3284357) and HEAD (daf3b93). Click for more details.

HEAD has 7 uploads less than BASE

Flag	BASE (3284357)	HEAD (daf3b93)
total	7	0

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #226       +/-   ##
==========================================
- Coverage   26.10%   0.00%   -26.11%     
==========================================
  Files         100      87       -13     
  Lines        9218    7868     -1350     
  Branches     2215     941     -1274     
==========================================
- Hits         2406       0     -2406     
- Misses       6423    7868     +1445     
+ Partials      389       0      -389     

Flag	Coverage Δ
differential	0.00% <0.00%> (?)
total	?

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[drwnz]

LGTM 👍