netdev - RE: [PATCH intel-next v2 0/8] i40e: support XDP multi-buffer

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>] [day] [month] [year] [list]

Date:   Tue, 14 Feb 2023 12:19:49 +0000
From:   "Sarkar, Tirthendu" <tirthendu.sarkar@...el.com>
To:     "intel-wired-lan@...ts.osuosl.org" <intel-wired-lan@...ts.osuosl.org>
CC:     "Brandeburg, Jesse" <jesse.brandeburg@...el.com>,
        "Nguyen, Anthony L" <anthony.l.nguyen@...el.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "bpf@...r.kernel.org" <bpf@...r.kernel.org>,
        "Karlsson, Magnus" <magnus.karlsson@...el.com>,
        "Fijalkowski, Maciej" <maciej.fijalkowski@...el.com>
Subject: RE: [PATCH intel-next v2 0/8] i40e: support XDP multi-buffer

Argh...this is a bit broken let me send next revision.

> -----Original Message-----
> From: Sarkar, Tirthendu <tirthendu.sarkar@...el.com>
> Sent: Tuesday, February 14, 2023 12:16 AM
> To: Sarkar, Tirthendu <tirthendu.sarkar@...el.com>
> Subject: [PATCH intel-next v2 0/8] i40e: support XDP multi-buffer
> 
> This patchset adds multi-buffer support for XDP. Tx side already has
> support for multi-buffer. This patchset focuses on Rx side. The last
> patch contains actual multi-buffer changes while the previous ones are
> preparatory patches.
> 
> On receiving the first buffer of a packet, xdp_buff is built and its
> subsequent buffers are added to it as frags. While 'next_to_clean' keeps
> pointing to the first descriptor, the newly introduced 'next_to_process'
> keeps track of every descriptor for the packet.
> 
> On receiving EOP buffer the XDP program is called and appropriate action
> is taken (building skb for XDP_PASS, reusing page for XDP_DROP, adjusting
> page offsets for XDP_{REDIRECT,TX}).
> 
> The patchset also streamlines page offset adjustments for buffer reuse
> to make it easier to post process the rx_buffers after running XDP prog.
> 
> With this patchset there does not seem to be any performance degradation
> for XDP_PASS and some improvement (~1% for XDP_TX, ~5% for
> XDP_DROP) when
> measured using xdp_rxq_info program from samples/bpf/ for 64B packets.
> 
> Changelog:
>     v1 -> v2:
>     - Instead of building xdp_buff on eop now it is built incrementally.
>     - xdp_buff is now added to i40e_ring struct for preserving across
>       napi calls. [Alexander Duyck]
>     - Post XDP program rx_buffer processing has been simplified.
>     - Rx buffer allocation pull out is reverted to avoid performance
>       issues for smaller ring sizes and now done when at least half of
>       the ring has been cleaned. With v1 there was ~75% drop for
>       XDP_PASS with the smallest ring size of 64 which is mitigated by
>       v2 [Alexander Duyck]
>     - Instead of retrying skb allocation on previous failure now the
>       packet is dropped. [Maciej]
>     - Simplified page offset adjustments by using xdp->frame_sz instead
>       of recalculating truesize. [Maciej]
>     - Change i40e_trace() to use xdp instead of skb [Maciej]
>     - Reserve tailroom for legacy-rx [Maciej]
>     - Centralize max frame size calculation
> 
> Tirthendu Sarkar (8):
>   i40e: consolidate maximum frame size calculation for vsi
>   i40e: change Rx buffer size for legacy-rx to support XDP multi-buffer
>   i40e: add pre-xdp page_count in rx_buffer
>   i40e: Change size to truesize when using i40e_rx_buffer_flip()
>   i40e: use frame_sz instead of recalculating truesize for building skb
>   i40e: introduce next_to_process to i40e_ring
>   i40e: add xdp_buff to i40e_ring struct
>   i40e: add support for XDP multi-buffer Rx
> 
>  drivers/net/ethernet/intel/i40e/i40e_main.c  |  75 ++--
>  drivers/net/ethernet/intel/i40e/i40e_trace.h |  20 +-
>  drivers/net/ethernet/intel/i40e/i40e_txrx.c  | 426 +++++++++++--------
>  drivers/net/ethernet/intel/i40e/i40e_txrx.h  |  21 +-
>  4 files changed, 311 insertions(+), 231 deletions(-)
> 
> --
> 2.34.1