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From: Alex Kiselev <kiselev99@gmail.com>
Date: Tue, 13 Feb 2018 22:37:37 +0300
Message-ID: <CAMKNYbw7=b69eCM17p8SperLRD86wtKw3iLj1FtG8gL7bUakNg@mail.gmail.com>
To: dev@dpdk.org
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Subject: [dpdk-dev] release/acquire memory barriers and ring
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Hi.

I've been wondering should I use a release/acquire memory barrier pair
in order to be sure that the other thread will see the fully/corrected
initialized object
passed to it via a dpdk ring or ring itself is a kind of barrier?

Let's say I have a pseudo code:

Thread1:
obj = alloc();
...
obj initialization
...

??? fence(memory_order_release); ???
rte_ring_sp_enqueue(ring, obj)


Thread2:
??? fence(memory_order_acquire); ???
rte_ring_sc_dequeue(ring, obj)

Should I use fences in that code?

Thanks.

--
Alex