netdev - Re: [PATCH net-next 0/2] inet: factorize sk_wmem

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Date:   Sun, 01 Apr 2018 14:09:07 -0400 (EDT)
From:   David Miller <davem@...emloft.net>
To:     edumazet@...gle.com
Cc:     netdev@...r.kernel.org, eric.dumazet@...il.com
Subject: Re: [PATCH net-next 0/2] inet: factorize sk_wmem_alloc updates

From: Eric Dumazet <edumazet@...gle.com>
Date: Sat, 31 Mar 2018 13:16:24 -0700

> While testing my inet defrag changes, I found that senders
> could spend ~20% of cpu cycles in skb_set_owner_w() updating
> sk->sk_wmem_alloc for every fragment they cook, competing
> with TX completion of prior skbs possibly happening on another cpus.
> 
> One solution to this problem is to use alloc_skb() instead
> of sock_wmalloc() and manually perform a single sk_wmem_alloc change.
> 
> This greatly increases speed for applications sending big UDP datagrams.

Looks good, series applied, thanks.