go.arm64
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4ad
sync/atomic, runtime: re-check all atomic operations
It seems our atomic operations might lack memory barriers, as I run misc/cgo/test for enough number of times, test9400 almost always timeout due to missed synchronization (esp. when GOMAXPROCS=8).
test9400 requires some assembly, and I coded in the same way as our sync/atomic functions, so if that test turns out to be wrong, our sync/atomic routines might be wrong too.
I'd believe that, the number of variations for the LDRX STRX variants available on arm64 is huge, it's easily to believe we're not using exactly the right one
On Sun, Feb 22, 2015 at 1:39 PM, Minux Ma [email protected] wrote:
It seems our atomic operations might lack memory barriers, as I run misc/cgo/test for enough number of times, test9400 almost always timeout due to missed synchronization (esp. when GOMAXPROCS=8).
test9400 requires some assembly, and I coded in the same way as our sync/atomic functions, so if that test turns out to be wrong, our sync/atomic routines might be wrong too.
— Reply to this email directly or view it on GitHub https://github.com/4ad/go/issues/139.
FWIW we are using the exact same atomics code as gcc. If we don't, I screwed something up.
