From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon@6wind.com>
Subject: Re: [PATCH v2] ring: check for zero objects mc dequeue /
	mp enqueue
Date: Tue, 22 Mar 2016 17:49:08 +0100
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References: <1458229783-15547-1-git-send-email-l@nofutznetworks.com>
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Cc: dev@dpdk.org, Olivier Matz <olivier.matz@6wind.com>
To: Lazaros Koromilas <l@nofutznetworks.com>
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> > Issuing a zero objects dequeue with a single consumer has no effect.
> > Doing so with multiple consumers, can get more than one thread to succeed
> > the compare-and-set operation and observe starvation or even deadlock in
> > the while loop that checks for preceding dequeues.  The problematic piece
> > of code when n = 0:
> > 
> >     cons_next = cons_head + n;
> >     success = rte_atomic32_cmpset(&r->cons.head, cons_head, cons_next);
> > 
> > The same is possible on the enqueue path.
> > 
> > Signed-off-by: Lazaros Koromilas <l@nofutznetworks.com>
> 
> Acked-by: Olivier Matz <olivier.matz@6wind.com>

Applied, thanks