From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 4/5] alx: add alx_get_stats operation
Date: Thu, 02 Jan 2014 12:39:21 -0500 (EST)
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From: Ben Hutchings <bhutchings@solarflare.com>
Date: Thu, 2 Jan 2014 11:56:53 +0000

> On Wed, 2014-01-01 at 22:27 -0500, David Miller wrote:
>> From: Sabrina Dubroca <sd@queasysnail.net>
>> Date: Thu,  2 Jan 2014 00:40:27 +0100
>> 
>> > +	spin_lock(&alx->stats_lock);
>> > +
>> > +	__alx_update_hw_stats(&alx->hw);
>> 
>> Please use something like the linux/u64_stats_sync.h stuff rather
>> than spin locking.
> 
> I don't think that'sa useful, as we can have multiple writers
> (concurrent calls to get_stats).  And there is really no harm in using a
> spinlock to serialise get_stats calls.  The u64_stats API is good for
> statistics updated from the data path.

Fair enough.