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Date: Wed, 10 Apr 2024 18:45:49 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Breno Leitao <leitao@debian.org>
Cc: davem@davemloft.net, pabeni@redhat.com, edumazet@google.com,
 linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [PATCH net-next v2 4/4] net: dqs: make struct dql more cache
 efficient
Message-ID: <20240410184549.5e5f77f2@kernel.org>
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On Wed, 10 Apr 2024 06:52:56 -0700 Breno Leitao wrote:
> > Doesn't this move the cache line bouncing problem to the other side?  
> 
> I think so. Looking at dql_check_stall(), it only uses fields in the
> second cache line, except now 'dql->stall_thrs' that is in the first
> cache line.

We do read num_queued at the beginning of dql_completed().
So maybe we we move the read of the threshold there we will be fine.