netdev - Re: [PATCH RFC net-next] ip_tunnel: create percpu gro

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1420844264.5947.81.camel@edumazet-glaptop2.roam.corp.google.com>
Date:	Fri, 09 Jan 2015 14:57:44 -0800
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Martin KaFai Lau <kafai@...com>
Cc:	netdev@...r.kernel.org, kernel-team@...com
Subject: Re: [PATCH RFC net-next] ip_tunnel: create percpu gro_cell

On Fri, 2015-01-09 at 10:42 -0800, Martin KaFai Lau wrote:
> In the ipip tunnel, the skb->queue_mapping is lost in ipip_rcv().
> All skb will be queued to the same cell->napi_skbs.  The
> gro_cell_poll is pinned to one core under load. In production traffic,
> we also see severe rx_dropped in the tunl iface and it is probably due to
> this limit: skb_queue_len(&cell->napi_skbs) > netdev_max_backlog
> 
> This patch is trying to alloc_percpu(struct gro_cell) and schedule
> gro_cell_poll to process it in the same core.


I wrote a similar patch here at Google, but I removed the
____cacheline_aligned_in_smp attribute on struct gro_cell

It was needed because of kcalloc(), but with alloc_percpu(), no gain
adding a padding.


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html