Date:   Wed, 1 Feb 2023 22:01:05 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Qingfang DENG <dqfext@gmail.com>
Cc:     Jesper Dangaard Brouer <hawk@kernel.org>,
        Ilias Apalodimas <ilias.apalodimas@linaro.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Lorenzo Bianconi <lorenzo@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        John Fastabend <john.fastabend@gmail.com>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net] net: page_pool: use in_softirq() instead
Message-ID: <20230201220105.410fee4c@kernel.org>
In-Reply-To: <20230202024417.4477-1-dqfext@gmail.com>
References: <20230202024417.4477-1-dqfext@gmail.com>
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On Thu,  2 Feb 2023 10:44:17 +0800 Qingfang DENG wrote:
> From: Qingfang DENG <qingfang.deng@siflower.com.cn>
> 
> We use BH context only for synchronization, so we don't care if it's
> actually serving softirq or not.
> 
> As a side node, in case of threaded NAPI, in_serving_softirq() will
> return false because it's in process context with BH off, making
> page_pool_recycle_in_cache() unreachable.

LGTM, but I don't think this qualifies as a fix.
It's just a missed optimization, right?