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Date:   Thu, 21 Jan 2021 09:36:05 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Ido Schimmel <idosch@idosch.org>
Cc:     Oleksandr Mazur <oleksandr.mazur@plvision.eu>,
        netdev@vger.kernel.org, jiri@nvidia.com, davem@davemloft.net,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next] net: core: devlink: add new trap action
 HARD_DROP
Message-ID: <20210121093605.49ba26ba@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
In-Reply-To: <20210121122152.GA2647590@shredder.lan>
References: <20210121112937.30989-1-oleksandr.mazur@plvision.eu>
        <20210121122152.GA2647590@shredder.lan>
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On Thu, 21 Jan 2021 14:21:52 +0200 Ido Schimmel wrote:
> On Thu, Jan 21, 2021 at 01:29:37PM +0200, Oleksandr Mazur wrote:
> > Add new trap action HARD_DROP, which can be used by the
> > drivers to register traps, where it's impossible to get
> > packet reported to the devlink subsystem by the device
> > driver, because it's impossible to retrieve dropped packet
> > from the device itself.
> > In order to use this action, driver must also register
> > additional devlink operation - callback that is used
> > to retrieve number of packets that have been dropped by
> > the device.  
> 
> Are these global statistics about number of packets the hardware dropped
> for a specific reason or are these per-port statistics?
> 
> It's a creative use of devlink-trap interface, but I think it makes
> sense. Better to re-use an existing interface than creating yet another
> one.

Not sure if I agree, if we can't trap why is it a trap?
It's just a counter.