Message-ID: <48429c16fdaee59867df5ef487e73d4b1bf099af.camel@redhat.com>
Subject: Re: [PATCH net] udp: fix memory schedule error
From:   Paolo Abeni <pabeni@redhat.com>
To:     Jason Xing <kerneljasonxing@gmail.com>,
        willemdebruijn.kernel@gmail.com, davem@davemloft.net,
        dsahern@kernel.org, edumazet@google.com, kuba@kernel.org
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        bpf@vger.kernel.org, Jason Xing <kernelxing@tencent.com>
Date:   Tue, 21 Feb 2023 13:27:39 +0100
In-Reply-To: <20230221110344.82818-1-kerneljasonxing@gmail.com>
References: <20230221110344.82818-1-kerneljasonxing@gmail.com>
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On Tue, 2023-02-21 at 19:03 +0800, Jason Xing wrote:
> From: Jason Xing <kernelxing@tencent.com>
>=20
> Quoting from the commit 7c80b038d23e ("net: fix sk_wmem_schedule()
> and sk_rmem_schedule() errors"):
>=20
> "If sk->sk_forward_alloc is 150000, and we need to schedule 150001 bytes,
> we want to allocate 1 byte more (rounded up to one page),
> instead of 150001"

I'm wondering if this would cause measurable (even small) performance
regression? Specifically under high packet rate, with BH and user-space
processing happening on different CPUs.

Could you please provide the relevant performance figures?

Thanks!

Paolo