netdev - Re: [PATCH iwl-next v4 5/6] ice: shorten ring stat names and add accessors

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Message-ID: <e3110f85-290c-47f1-800a-9430afed5abc@intel.com>
Date: Wed, 3 Dec 2025 14:17:28 -0800
From: Jacob Keller <jacob.e.keller@...el.com>
To: Simon Horman <horms@...nel.org>
CC: Aleksandr Loktionov <aleksandr.loktionov@...el.com>, Alexander Lobakin
	<aleksander.lobakin@...el.com>, Tony Nguyen <anthony.l.nguyen@...el.com>,
	Przemek Kitszel <przemyslaw.kitszel@...el.com>,
	<intel-wired-lan@...ts.osuosl.org>, <netdev@...r.kernel.org>
Subject: Re: [PATCH iwl-next v4 5/6] ice: shorten ring stat names and add
 accessors



On 11/25/2025 2:17 AM, Simon Horman wrote:
> On Thu, Nov 20, 2025 at 12:20:45PM -0800, Jacob Keller wrote:
>> The ice Tx/Rx hotpath has a few statistics counters for tracking unexpected
>> events. These values are stored as u64 but are not accumulated using the
>> u64_stats API. This could result in load/tear stores on some architectures.
>> Even some 64-bit architectures could have issues since the fields are not
>> read or written using ACCESS_ONCE or READ_ONCE.
>>
>> A following change is going to refactor the stats accumulator code to use
>> the u64_stats API for all of these stats, and to use u64_stats_read and
>> u64_stats_inc properly to prevent load/store tears on all architectures.
>>
>> Using u64_stats_inc and the syncp pointer is slightly verbose and would be
>> duplicated in a number of places in the Tx and Rx hot path. Add accessor
>> macros for the cases where only a single stat value is touched at once. To
>> keep lines short, also shorten the stats names and convert ice_txq_stats
>> and ice_rxq_stats to struct_group.
>>
>> This will ease the transition to properly using the u64_stats API in the
>> following change.
>>
>> Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@...el.com>
>> Signed-off-by: Jacob Keller <jacob.e.keller@...el.com>
> 
> I had to read this and the next patch a few times to understand what was
> going on. In the end, the key for me understanding this patch is "...
> accessor macros for the cases where only a single stat value is touched at
> once.". Especially the "once" bit.
> 

I'm a little unhappy with needing access macros like this because its
yet another "driver specific wrapper".. but I couldn't come up with
something better..

> In the context of the following patch I think this change makes sense.
> And I appreciate that keeping lines short also makes sense. So no
> objections to the direction you've taken here. But I might not have
> thought to use struct_group for this myself.
> 

Right. The main issue I had was all the places where we increment one
stat we'd end up needing *at least* 3 lines. And trying to split or
refactor all of those updates seemed like it would be problematic.

I liked the use of struct_group since it lets us keep size information
and logical separation without needing to add the extra layer of
indirection in the accesses.

> Reviewed-by: Simon Horman <horms@...nel.org>



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