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Re: [PATCH] malloc: Revert fastbins to old-style atomics

* Siddhesh Poyarekar:

> On 18/01/19 5:46 PM, Florian Weimer wrote:
>> Siddhesh, is this okay to commit before the release?
>
> This is OK.  +1 on putting the patch back in once master reopens and get
> architecture maintainers to do an RCA.

I've pushed the revert.

I looked at this some more (including the POWER disassembly), and I
think the old code approximates what would happen with
memory_order_consume (if we had a working implementation of that) and
exploits the data dependency detection in the CPU to reduce the need for
barriers.

Thanks,
Florian
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