Re: [PATCH net-next 0/4] net: Convert some UDP tunnel drivers to NETDEV_PCPU_STAT_DSTATS.

[James Chapman <jchapman@katalix.com>]

Hi Guillaume,

I can work on similar changes to l2tp if you haven't already started 
work on it.

James

On 02/12/2024 21:48, Guillaume Nault wrote:
> VXLAN, Geneve and Bareudp use various device counters for managing
> RX and TX statistics:
> 
>    * VXLAN uses the device core_stats for RX and TX drops, tstats for
>      regular RX/TX counters and DEV_STATS_INC() for various types of
>      RX/TX errors.
> 
>    * Geneve uses tstats for regular RX/TX counters and DEV_STATS_INC()
>      for everything else, include RX/TX drops.
> 
>    * Bareudp, was recently converted to follow VXLAN behaviour, that is,
>      device core_stats for RX and TX drops, tstats for regular RX/TX
>      counters and DEV_STATS_INC() for other counter types.
> 
> Let's consolidate statistics management around the dstats counters
> instead. This avoids using core_stats in VXLAN and Bareudp, as
> core_stats is supposed to be used by core networking code only (and not
> in drivers).  This also allows Geneve to avoid using atomic increments
> when updating RX and TX drop counters, as dstats is per-cpu. Finally,
> this also simplifies the code as all three modules now handle stats in
> the same way and with only two different sets of counters (the per-cpu
> dstats and the atomic DEV_STATS_INC()).
> 
> Patch 1 creates dstats helper functions that can be used outside of VRF
> (before that, dstats was VRF-specific).
> Patches 2 to 4 convert VXLAN, Geneve and Bareudp, one by one.
> 
> Guillaume Nault (4):
>    vrf: Make pcpu_dstats update functions available to other modules.
>    vxlan: Handle stats using NETDEV_PCPU_STAT_DSTATS.
>    geneve: Handle stats using NETDEV_PCPU_STAT_DSTATS.
>    bareudp: Handle stats using NETDEV_PCPU_STAT_DSTATS.
> 
>   drivers/net/bareudp.c          | 16 ++++++------
>   drivers/net/geneve.c           | 12 ++++-----
>   drivers/net/vrf.c              | 46 +++++++++-------------------------
>   drivers/net/vxlan/vxlan_core.c | 28 ++++++++++-----------
>   include/linux/netdevice.h      | 40 +++++++++++++++++++++++++++++
>   5 files changed, 80 insertions(+), 62 deletions(-)
> 

-- 
James Chapman
Katalix Systems Ltd
https://katalix.com
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