On Mon, Jun 29, 2015 at 6:11 AM, Andres Freund <andres(at)anarazel(dot)de> wrote:
> On 2015-06-29 00:42:53 -0400, Tom Lane wrote:
>> #define S_UNLOCK(lock) \
>> do { _Asm_sched_fence(); (*(lock)) = 0; } while (0)
>
> Robert, how did you choose that? Isn't _Asm_sched_fence just a compiler
> barrier? Shouldn't this be a _Asm_mf()?
The point of the commit was to make spinlocks act as compiler barriers
as well as CPU barriers. So I was just looking to add a compiler
barrier to what was already there.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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