rtic-sync: No need for c-s to check if link is in wait queue if link is popped #1042
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This will block merging of #1038, so will wait until that is in :) ETA: I am entirely lying. Will merge this |
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Minor improvement: if we insert our link into the wait queue, we always take a critical section (in the
OnDrop) to ensure that it is no longer in the list on drop.However, if our link is popped, we know for a fact that it is not in the list.
take()-ing it in the block that gets us into that state saves us an unnecessary critical section, which is probably the 2nd-most common scenario (the 1st being finding a free slot immediately).Additionally, we take a critical-section to check whether we still have an entry in our
SlotPtr. However, once we are certain that ourlinkis removed from the list, we have exclusive access to it again: hence, we can skip that critical section too, on the happy path.