linux-kernel - Re: [resend PATCH 2/2] dim: pass dim_sample to net

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Message-ID: <20241103122138.6d0d62f6@kernel.org>
Date: Sun, 3 Nov 2024 12:21:38 -0800
From: Jakub Kicinski <kuba@...nel.org>
To: Caleb Sander Mateos <csander@...estorage.com>
Cc: Andrew Lunn <andrew+netdev@...n.ch>, AngeloGioacchino Del Regno
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Subject: Re: [resend PATCH 2/2] dim: pass dim_sample to net_dim() by
 reference

On Wed, 30 Oct 2024 18:23:26 -0600 Caleb Sander Mateos wrote:
> In a heavy TCP workload, mlx5e_handle_rx_dim() consumes 3% of CPU time,
> 94% of which is attributed to the first push instruction to copy
> dim_sample on the stack for the call to net_dim():

Change itself looks fine, so we can apply, but this seems surprising.
Are you sure this is not just some measurement problem?
Do you see 3% higher PPS with this change applied?