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Date:   Sun, 31 Jan 2021 12:48:28 +0000
To:     Matthew Wilcox <willy@infradead.org>
From:   Alexander Lobakin <alobakin@pm.me>
Cc:     Alexander Lobakin <alobakin@pm.me>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
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        Salil Mehta <salil.mehta@huawei.com>,
        Jesse Brandeburg <jesse.brandeburg@intel.com>,
        Tony Nguyen <anthony.l.nguyen@intel.com>,
        Saeed Mahameed <saeedm@nvidia.com>,
        Leon Romanovsky <leon@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
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Reply-To: Alexander Lobakin <alobakin@pm.me>
Subject: Re: [PATCH v3 net-next 5/5] net: page_pool: simplify page recycling condition tests
Message-ID: <20210131124802.8430-1-alobakin@pm.me>
In-Reply-To: <20210131122348.GM308988@casper.infradead.org>
References: <20210131120844.7529-1-alobakin@pm.me> <20210131120844.7529-6-alobakin@pm.me> <20210131122348.GM308988@casper.infradead.org>
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From: Matthew Wilcox <willy@infradead.org>
Date: Sun, 31 Jan 2021 12:23:48 +0000

> On Sun, Jan 31, 2021 at 12:12:11PM +0000, Alexander Lobakin wrote:
> > pool_page_reusable() is a leftover from pre-NUMA-aware times. For now,
> > this function is just a redundant wrapper over page_is_pfmemalloc(),
> > so inline it into its sole call site.
>=20
> Why doesn't this want to use {dev_}page_is_reusable()?

Page Pool handles NUMA on its own. Replacing plain page_is_pfmemalloc()
with dev_page_is_reusable() will only add a completely redundant and
always-false check on the fastpath.

Al