Improve multiple accessing pxCurrentTCB in a function #1065
+247
−202
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Description
Address Richard's feedback to update the usage of
pxCurrentTCB
in a function.Since
pxCurrentTCB
is a volatile variable, accessing it multiple times in a function can be slow if this pointer is not changed.In this PR:
prvGetCurrentTCB()
andprvGetCurrentTCBUnsafe()
functions are provided.prvGetCurrentTCBUnsafe()
can improve performance in SMP environments as it does not disable/enable interrupts. However, it should only be called in contexts where race conditions cannot occur.Test Steps
The performance gain is evaluated by comparing main branch with this PR with a hardware cycle counter.
We use the following example to illustrate the performance gain on
ulTaskGenericNotifyTake
.In the example above, bottom half of the
ulTaskGenericNotifyTake
are evaluated with compile option ( -O3 ).Checklist:
Related Issue
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