topology: Don't allocate on calls to span() #241
Merged
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We're currently cloning cpumasks returned by calls to {Core, Cache, Node, Topology}::span(). If a caller needs to clone it, they can. Let's not penalize the callers that just want to query the underlying cpumask.
We might be able to further optimize -- the trait implementations for bitwise operations on Cpumasks don't take references on the rhs, so we're doing extra clones where we shouldn't need to. I also wasn't able to figure out how to iterate over the bits set in the underlying cpumask without using
.into_iter()
, which requires cloning as well.