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Date: Tue, 21 Nov 2017 16:08:16 -0800
From: Gleb Smirnoff <glebius@FreeBSD.org>
To: Marcin Wojtas <mw@FreeBSD.org>, Michal Krawczyk <mk@semihalf.com>
Cc: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: Re: svn commit: r325239 - head/sys/dev/ena
Message-ID: <20171122000816.GH1063@FreeBSD.org>
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X-List-Received-Date: Wed, 22 Nov 2017 00:08:24 -0000

  Hi Martin and Michal,

On Tue, Oct 31, 2017 at 04:31:23PM +0000, Marcin Wojtas wrote:
M> Author: mw
M> Date: Tue Oct 31 16:31:23 2017
M> New Revision: 325239
M> URL: https://svnweb.freebsd.org/changeset/base/325239
M> 
M> Log:
M>   Rework counting of hardware statistics in ENA driver
M>   
M>   Do not read all statistics from the device, instead count them in the
M>   driver except from RX drops - they are received directly from the NIC
M>   in the AENQ descriptor.
M>   
M>   Submitted by: Michal Krawczyk <mk@semihalf.com>
M>   Reviewed by: imp
M>   Obtained from: Semihalf
M>   Sponsored by: Amazon.com, Inc.
M>   Differential Revision: https://reviews.freebsd.org/D12852

Is it possible not to count them in software, as well as not fetch
them from hardware periodically, but instead just fetch them on
demand, when either if_get_counter() or a sysctl is called?

That would be more efficient.

-- 
Gleb Smirnoff