Add cacheline-alignment to compiler/threading and switch from volatile to std::atomic #1005
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Signed-off-by: Valery Matskevich <[email protected]>
Signed-off-by: Valery Matskevich <[email protected]>
Signed-off-by: Valery Matskevich <[email protected]>
mkornaukhov03
requested changes
May 24, 2024
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| HTNode *at(unsigned long long hash) { | ||
| int i = (unsigned)hash % (unsigned)N; | ||
| while (true) { | ||
| while (nodes[i].hash != 0 && nodes[i].hash != hash) { | ||
| while (nodes[i].hash.load(std::memory_order_acquire) != 0 && nodes[i].hash.load(std::memory_order_relaxed) != hash) { |
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Why second read is relaxed?
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because it won't be reordered between nodes[i].hash.load(std::memory_order_acquire) before and nodes[i].hash.load(std::memory_order_acquire) after, the only barrier needed here is load-load, which is imposed by reading node hash
Signed-off-by: Valery Matskevich <[email protected]>
Signed-off-by: Valery Matskevich <[email protected]>
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Refactor compiler/threading:
std::atomicinstead ofvolatilealignasto cache-align shared structs