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Date:   Mon, 24 Oct 2022 21:24:19 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Saeed Mahameed <saeed@kernel.org>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Paolo Abeni <pabeni@redhat.com>,
        Eric Dumazet <edumazet@google.com>,
        Saeed Mahameed <saeedm@nvidia.com>, netdev@vger.kernel.org,
        Tariq Toukan <tariqt@nvidia.com>,
        Yevgeny Kliteynik <kliteyn@nvidia.com>,
        Alex Vesker <valex@nvidia.com>
Subject: Re: [net-next 05/14] net/mlx5: DR, Allocate ste_arr on stack
 instead of dynamically
Message-ID: <20221024212419.003b3056@kernel.org>
In-Reply-To: <20221024135734.69673-6-saeed@kernel.org>
References: <20221024135734.69673-1-saeed@kernel.org>
        <20221024135734.69673-6-saeed@kernel.org>
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On Mon, 24 Oct 2022 14:57:25 +0100 Saeed Mahameed wrote:
> From: Yevgeny Kliteynik <kliteyn@nvidia.com>
>=20
> While creting rule, ste_arr is a short array that is allocated in
> the beginning of the function and freed at the end.
> To avoid memory allocation "hiccups" that sometimes take up to 10ms,
> allocate it on stack.

There's a reason, 32bit x86 does not like this:

drivers/net/ethernet/mellanox/mlx5/core/steering/dr_rule.c: In function =E2=
=80=98dr_rule_create_rule_nic=E2=80=99:
drivers/net/ethernet/mellanox/mlx5/core/steering/dr_rule.c:1202:1: warning:=
 the frame size of 1568 bytes is larger than 1024 bytes [-Wframe-larger-tha=
n=3D]
1202 | }
     | ^