From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [dpdk-stable] [PATCH v4 4/4] ring: move the atomic
	load of head above the loop
Date: Sat, 27 Oct 2018 16:21:15 +0200
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Cc: stable@dpdk.org, dev@dpdk.org, Honnappa.Nagarahalli@arm.com,
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To: Gavin Hu <gavin.hu@arm.com>
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17/09/2018 10:11, Gavin Hu:
> In __rte_ring_move_prod_head, move the __atomic_load_n up and out of
> the do {} while loop as upon failure the old_head will be updated,
> another load is costly and not necessary.
> 
> This helps a little on the latency,about 1~5%.
> 
>  Test result with the patch(two cores):
>  SP/SC bulk enq/dequeue (size: 8): 5.64
>  MP/MC bulk enq/dequeue (size: 8): 9.58
>  SP/SC bulk enq/dequeue (size: 32): 1.98
>  MP/MC bulk enq/dequeue (size: 32): 2.30
> 
> Fixes: 39368ebfc6 ("ring: introduce C11 memory model barrier option")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Gavin Hu <gavin.hu@arm.com>
> Reviewed-by: Honnappa Nagarahalli <Honnappa.Nagarahalli@arm.com>
> Reviewed-by: Steve Capper <steve.capper@arm.com>
> Reviewed-by: Ola Liljedahl <Ola.Liljedahl@arm.com>

We are missing reviews and acknowledgements on this series.