From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH v3 0/6] use IOVAs check based on DMA mask
Date: Mon, 29 Oct 2018 12:46:45 +0100
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Cc: lei.a.yao@intel.com, dev <dev@dpdk.org>, "Xu, Qian Q" <qian.q.xu@intel.com>,
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To: Alejandro Lucero <alejandro.lucero@netronome.com>
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29/10/2018 12:39, Alejandro Lucero:
> I got a patch that solves a bug when calling rte_eal_dma_mask using the
> mask instead of the maskbits. However, this does not solves the deadlock.

The deadlock is a bigger concern I think.

> Interestingly, the problem looks like a compiler one. Calling
> rte_memseg_walk does not return when calling inside rt_eal_dma_mask, but if
> you modify the call like this:
> 
> -       if (rte_memseg_walk(check_iova, &mask))
> +       if (!rte_memseg_walk(check_iova, &mask))
> 
> it works, although the value returned to the invoker changes, of course.
> But the point here is it should be the same behaviour when calling
> rte_memseg_walk than before and it is not.

Anyway, the coding style requires to save the return value in a variable,
instead of nesting the call in an "if" condition.
And the "if" check should be explicitly != 0 because it is not a real boolean.

PS: please do not top post and avoid HTML emails, thanks