Revise CachePadded #130
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Revise CachePadded #130
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arthurprs
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Apr 14, 2017
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Seems strictly better than what we have 👍
arthurprs
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Apr 14, 2017
| #[cfg_attr(feature = "nightly", repr(simd))] | ||
| #[derive(Debug)] | ||
| struct Padding(u64, u64, u64, u64); | ||
| struct Padding([usize; CACHE_LINE]); |
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We need to make it u/i/XX in order to compile on nightly.
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A heads up, the alignment feature (rust-lang/rust#39999) just landed and should be available on nightly soon :) |
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Closing it, as |
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Here are the changes I made:
Add documentation (originally written by @ticki in Major-release candidate #122)
Make the padding trick more readable. Though I am not sure of its correctness (https://github.com/jeehoonkang/crossbeam/blob/cachepadded/src/cache_padded.rs#L15). Would anyone please verify it? Also I am wondering if there is a documentation on this trick.
Split pad from the marker in
CachePadded.Add an assertion in
assert_valid.Remove validity check when dereferencing and dropping
CachePadded.Remaining questions:
Is it better to describe the cache line size as
CONST * sizeof(usize)? Why not just write down the size in bytes?I think eventually
CACHE_LINEshould depend on the (micro-)architecture. But I cannot find any existing C/C++ library on it. Do anyone have an idea/pointer on this?Alternatively, we can get the cache line size from the environmental variable, with 64 bytes as default.
How to support
Twhose size is bigger thanCACHE_LINE? It is needed when we want the cache line size to be 64 bytes, assizeof(Participant)> 64.