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Date:   Mon, 19 Apr 2021 11:55:54 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Ido Schimmel <idosch@idosch.org>
Cc:     netdev@vger.kernel.org, davem@davemloft.net, andrew@lunn.ch,
        mkubecek@suse.cz, idosch@nvidia.com, saeedm@nvidia.com,
        michael.chan@broadcom.com
Subject: Re: [PATCH net-next v2 6/9] ethtool: add interface to read RMON
 stats
Message-ID: <20210419115554.000e05dd@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
In-Reply-To: <YHvoABffbJQxKmfI@shredder>
References: <20210416192745.2851044-1-kuba@kernel.org>
        <20210416192745.2851044-7-kuba@kernel.org>
        <YHvoABffbJQxKmfI@shredder>
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On Sun, 18 Apr 2021 11:04:16 +0300 Ido Schimmel wrote:
> On Fri, Apr 16, 2021 at 12:27:42PM -0700, Jakub Kicinski wrote:
> > +/**
> > + * struct ethtool_rmon_hist_range - byte range for histogram statistics
> > + * @low: low bound of the bucket (inclusive)
> > + * @high: high bound of the bucket (inclusive)
> > + */
> > +struct ethtool_rmon_hist_range {
> > +	u16 low;
> > +	u16 high;  
> 
> Given ETHTOOL_A_STATS_GRP_HIST_BKT_{LOW,HI} are u32, should this also be
> u32?

I felt a little bad about wasting memory in each driver. It's around
40B per driver. I thought we can adjust when needed given this is
internal to the kernel, and static checkers should have no problem
detecting truncation (or any rudimentary testing).