Remove support for tmrCOMMAND_START_DONT_TRACE (#305)

* Remove support for tmrCOMMAND_START_DONT_TRACE

Prior to this commit, the timer task used tmrCOMMAND_START_DONT_TRACE
to reload a "backlogged" auto-reload timer -- one for which a reload
operation would have started a period that had already elapsed.  If the
command queue contained a stop or delete command when
tmrCOMMAND_START_DONT_TRACE was put into the queue for a reload, the
timer unexpectedly restarted when the timer task processed
tmrCOMMAND_START_DONT_TRACE.  This commit implements a new method of
reloading auto-reload timers and eliminates support for
tmrCOMMAND_START_DONT_TRACE.  No other code sends this private command.

However, the symbol tmrCOMMAND_START_DONT_TRACE remains defined, with
its original command value, so as not to impact trace applications.

Also fix one-shot timers that were not reliably being marked as not
- when they expired before the start command could be processed
- when the expiration was processed during the timer list switch

Also improve consistency:
- Always reload auto-reload timers *before* calling the callback.
- Always call traceTIMER_EXPIRED() just prior to the callback.

* fix indent

* Revert unnecessary change to prvTimerTask()

Change was intended to faithfully work through a backlog that spanned a
list switch, and before processing a stop or delete command.  But, (1)
it isn't important to do that, and (2) the code didn't accomplish the
intention when *two* auto-reload timers were backlogged across a list
switch.  Best to simply leave this part of the code as it was before.

* fix style

Co-authored-by: Joseph Julicher <>
1 file changed
tree: dc10c2c1de2c9266408b84672d31c0f886d64bc8
  1. .github/
  2. GitHub-FreeRTOS-Kernel-Home.url
  3. History.txt
  5. Quick_Start_Guide.url
  7. croutine.c
  8. event_groups.c
  9. include/
  10. list.c
  11. portable/
  12. queue.c
  13. stream_buffer.c
  14. tasks.c
  15. timers.c

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