Re: [PATCH 2/7] ixgbe: eliminate duplicate barriers on weakly-ordered archs

From: Alexander Duyck
Date: Wed Mar 14 2018 - 21:47:30 EST


On Tue, Mar 13, 2018 at 8:20 PM, Sinan Kaya <okaya@xxxxxxxxxxxxxx> wrote:
> Code includes wmb() followed by writel() in multiple places. writel()
> already has a barrier on some architectures like arm64.
>
> This ends up CPU observing two barriers back to back before executing the
> register write.
>
> Since code already has an explicit barrier call, changing writel() to
> writel_relaxed().
>
> Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>

In this patch you missed the writel at the end of ixgbe_tx_map.