Ok, technically we both used the weasel word 'can' so we are both right.
But even on ARM, these days store releases and load acquires, while not as free as on x86 are very cheap.
To make my statement more precise, typically what is still expensive pretty much everywhere is anything with #StoreLoad barrier semantics, which is what you need to acquire a mutex.
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Ok, technically we both used the weasel word 'can' so we are both right.
But even on ARM, these days store releases and load acquires, while not as free as on x86 are very cheap.
To make my statement more precise, typically what is still expensive pretty much everywhere is anything with #StoreLoad barrier semantics, which is what you need to acquire a mutex.