From mboxrd@z Thu Jan  1 00:00:00 1970
From: Adrien Mazarguil <adrien.mazarguil@6wind.com>
Subject: Re: [PATCH] net/mlx: remove link update lock
Date: Mon, 16 Jan 2017 15:03:23 +0100
Message-ID: <20170116140323.GD3779@6wind.com>
References: <1484153041-18034-1-git-send-email-olivier.matz@6wind.com>
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Cc: dev@dpdk.org, Matthieu Ternisien d'Ouville <matthieu.tdo@6wind.com>
To: Olivier Matz <olivier.matz@6wind.com>
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On Wed, Jan 11, 2017 at 05:44:01PM +0100, Olivier Matz wrote:
> From: Matthieu Ternisien d'Ouville <matthieu.tdo@6wind.com>
> 
> Retrieving link status information through the link update callback should
> be quick and non-blocking.
> 
> Mellanox PMDs retrieve this information through ioctl() calls on the
> related kernel netdevice. This appears to take a long time to
> complete and may cause significant slowdowns in applications.
> 
> While these system calls cannot be accelerated, removing the lock on the
> private structure allows applications to perform other control operations
> from separate threads in the meantime. This function remains safe without
> locking as it does not write the private structure, it is only used to
> retrieve the name of the netdevice.
> 
> Signed-off-by: Matthieu Ternisien d'Ouville <matthieu.tdo@6wind.com>
> Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
> ---
>  drivers/net/mlx4/mlx4.c        | 32 ++++++--------------------------
>  drivers/net/mlx5/mlx5.c        |  2 +-
>  drivers/net/mlx5/mlx5.h        |  1 -
>  drivers/net/mlx5/mlx5_ethdev.c | 30 ++++++------------------------
>  4 files changed, 13 insertions(+), 52 deletions(-)

Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>

-- 
Adrien Mazarguil
6WIND