On 01/24/2017 01:08 AM, Torvald Riegel wrote: > Unless HW transactions are guaranteed to succeed for scenarios that are > sufficient for the atomics, HTM won't help because we'd have to consider > the worst-case, which would mean some non-HTM fallback.
We're talking about a 16 byte aligned load here -- one cacheline, probably 3-4 instructions. If an HTM cannot succeed with that, I'm happy to call it useless. The only possible concern I see might be with simulators that force HTM failure, for the purpose of forcibly testing fallback paths. I guess we'd have to continue to fall back to the lock path for that case. r~
