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From:   Oleksandr Mazur <oleksandr.mazur@plvision.eu>
To:     Jakub Kicinski <kuba@kernel.org>
CC:     "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "jiri@nvidia.com" <jiri@nvidia.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [RFC v3 net-next] net: core: devlink: add 'dropped' stats field
 for DROP trap action
Thread-Topic: [RFC v3 net-next] net: core: devlink: add 'dropped' stats field
 for DROP trap action
Thread-Index: AQHW8xcXY5euT+iepUq2JFXYOtkL6Ko42mmAgAWdF96AAImvgIAEbH7J
Date:   Mon, 1 Feb 2021 14:54:55 +0000
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=0A=
On Fri, 29 Jan 2021 11:15:43 +0000 Oleksandr Mazur wrote:=0A=
> > >Thinking about it again - if the action can be changed wouldn't it =0A=
> > >be best for the user to actually get a "HW condition hit" counter,=0A=
> >> which would increment regardless of SW config (incl. policers)?=A0 =0A=
> >=0A=
> > >Otherwise if admin logs onto the box and temporarily enables a trap =
=0A=
> >> for debug this count would disappear.=A0 =0A=
>> =0A=
>> But still this counter makes sense only for 'drop' action.=0A=
=0A=
>Okay, well, "dropped while trap was disabled" seems a lot less useful=0A=
>of a definition than "number of times this trap would trigger" but if=0A=
>that's all the HW can provide then it is what it is.=0A=
=0A=
>Does the HW also count packets dropped because of overload / overflow=0A=
>or some other event, or purely dropped because disabled?=0A=
=0A=
Hw starts counting traffic (hw drops) only when action has been explicitly =
set to be 'DROP';=