From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8C3E9341360 for ; Wed, 17 Sep 2025 15:39:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758123571; cv=none; b=Cx/yqmr0OjHK+KlZ8O9yu0VFJzRrJUcixr94VtT/Kx36ueYkEx6lLPTqRs18fKzp45YMvzppxmkiQvcA88AG/PAY19rwX10rFqGXFVilXFbfmbrHSKEauADK8LeOCkI4FQ1DYgLM8VEgakc03m1SzVNtQhPIJXuWMF6zEZdONIg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758123571; c=relaxed/simple; bh=az/OFVz230XFrSks6xi2HFyjTWpfolow49KvdHiw9/Q=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=uPX+DqFQXfEp0cNqSo0peFG+3cYWCqOmqA5HUjKNIUuXaNTIH8LY+aK/nagUECQMccPkYbJPzekUFRCdtxW7inE2mlKT63ySu6bYBrI6VWetYrQJrzQONnE/0WeNQ8qb/VORlh0tgXw8fe4d7BkmQUUXHof2LP0htuxJuRc3LfQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RCMljDv9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RCMljDv9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AF350C4CEE7; Wed, 17 Sep 2025 15:39:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758123571; bh=az/OFVz230XFrSks6xi2HFyjTWpfolow49KvdHiw9/Q=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=RCMljDv956cLY0VUTSA/XUGm/U14izZiktQAp8QAlHM2Rhovm4FnIjpAjTC1Ppjb0 +D+fFbdoUpp61QEiTyft0Ll65SWIgk8YpUCGWe/yINJZQm4KisMDm1J3KdHLtNKlru UWPLZpc99sO7YgaOsn6gkwjxCCUlrdfRbqNAEJrPa1Dr8Pokk5Xo/yuDzs8phd5NJL W94seUd55n4N7BFqwqnqijQqvWXup2H3DFgtEN1kZ/bl3ORrhsl03FRIPIzs9IuZZZ H/OHy8C1ybqwXTLxoS7NDJwwm1hOT7pVDGdFUOXzM/M4eel6iklaXZ9iHROoVNbFI4 i5UoXJ3FQC3wg== Message-ID: Date: Wed, 17 Sep 2025 09:39:30 -0600 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next 05/10] udp: refine __udp_enqueue_schedule_skb() test Content-Language: en-US To: Eric Dumazet , "David S . Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , Willem de Bruijn , Kuniyuki Iwashima , netdev@vger.kernel.org, eric.dumazet@gmail.com References: <20250916160951.541279-1-edumazet@google.com> <20250916160951.541279-6-edumazet@google.com> From: David Ahern In-Reply-To: <20250916160951.541279-6-edumazet@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 9/16/25 10:09 AM, Eric Dumazet wrote: > Commit 5a465a0da13e ("udp: Fix multiple wraparounds > of sk->sk_rmem_alloc.") allowed to slightly overshoot > sk->sk_rmem_alloc, when many cpus are trying > to feed packets to a common UDP socket. > > This patch, combined with the following one reduces > false sharing on the victim socket under DDOS. > > Signed-off-by: Eric Dumazet > --- > net/ipv4/udp.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > Reviewed-by: David Ahern