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Date: Wed, 23 Aug 2023 07:53:18 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: linux@weissschuh.net
Cc: "David S. Miller" <davem@davemloft.net>, Eric Dumazet
 <edumazet@google.com>, Paolo Abeni <pabeni@redhat.com>,
 netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Robert Marko
 <robimarko@gmail.com>
Subject: Re: [PATCH net-next] net: generalize calculation of skb extensions
 length
Message-ID: <20230823075318.4860cebc@kernel.org>
In-Reply-To: <1e1dde74-edc6-4306-9b1b-0a1b5a658b67@weissschuh.net>
References: <20230822-skb_ext-simplify-v1-1-9dd047340ab5@weissschuh.net>
	<20230822184644.18966d0f@kernel.org>
	<1e1dde74-edc6-4306-9b1b-0a1b5a658b67@weissschuh.net>
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On Wed, 23 Aug 2023 10:14:48 +0200 (GMT+02:00) linux@weissschuh.net
wrote:
> > Could you include more info about the compiler versions you tried
> > and maybe some objdump? We'll have to take your word for it getting
> > optimized out, would be great if we had more proof in the commit msg.
> > --
> > pw-bot: cr  
> 
> Thanks for the feedback.
> I'll send a v2 with more background soon.
> 
> On the other hand this function is only ever
> executed once, so even if it is slightly inefficient
> it shouldn't matter.

Oh you're right, somehow I thought it was for every alloc.
You can mention it's only run at init in the commit msg if 
that's easier.