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Date:   Thu, 15 Jun 2023 19:45:24 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Jesper Dangaard Brouer <jbrouer@redhat.com>
Cc:     Liang Chen <liangchen.linux@gmail.com>, brouer@redhat.com,
        hawk@kernel.org, ilias.apalodimas@linaro.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        davem@davemloft.net, edumazet@google.com, pabeni@redhat.com
Subject: Re: [PATCH net-next] page pool: not return page to alloc cache
 during pool destruction
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        <b28b0e3e-87e4-5a02-c172-2d1424405a5a@redhat.com>
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On Thu, 15 Jun 2023 16:00:13 +0200 Jesper Dangaard Brouer wrote:
> Adding a DEBUG_NET_WARN_ON_ONCE will be annoying as I like to run my
> testlab kernels with CONFIG_DEBUG_NET, which will change this extreme
> fash-path slightly (adding some unlikely's affecting code layout to the
> mix).

That's counter-intuitive - the whole point of DEBUG_NET is to have 
a place where we can add checks which we don't want in production
builds. If we can't use it on the datapath we should just remove it
completely and have its checks always enabled..

I do feel your pain of having to test code both with debug enabled
and disabled, but we can't have a cookie and eat it too :(