perf(main): write dshot NVIC priorities only on actual change#11
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perf(main): write dshot NVIC priorities only on actual change#11dakejahl wants to merge 1 commit into
dakejahl wants to merge 1 commit into
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The dshot telemetry priority swap wrote three or four NVIC registers on every main loop iteration even though the scheme flips rarely. Track the current scheme in input_priority_is_high and skip the writes when nothing changed. The 0xFF boot sentinel forces the first pass to write, preserving the old boot behavior exactly. input_priority_is_high is a static local scoped to the priority block rather than a file global, so it also disappears on the MCU_G031 and NEED_INPUT_READY targets that compile the block out.
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Summary
Write the DShot input / commutation NVIC priorities only when the desired priority scheme actually changes, instead of re-applying it on every main-loop pass.
Problem
Every main-loop iteration unconditionally called
NVIC_SetPriority()for several interrupts based ondshot_telemetry && commutation_interval > threshold. That condition rarely changes, so the loop kept rewriting the same priority values.Solution
Track the current scheme in
input_priority_is_high(initialised to 0xFF so the first pass always applies it) and callNVIC_SetPriority()only on a transition. Identical resulting priorities, fewer register writes per loop. The flag is astaticlocal scoped to the priority block rather than a file-scope global, so it also drops off theMCU_G031/NEED_INPUT_READYtargets that compile the block out.