From f858cc9eed5b05cbe38d7ffd2787c21e3718eb7d Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 3 Oct 2024 12:12:18 +0000 Subject: net: add IFLA_MAX_PACING_OFFLOAD_HORIZON device attribute Some network devices have the ability to offload EDT (Earliest Departure Time) which is the model used for TCP pacing and FQ packet scheduler. Some of them implement the timing wheel mechanism described in https://saeed.github.io/files/carousel-sigcomm17.pdf with an associated 'timing wheel horizon'. This patch adds dev->max_pacing_offload_horizon expressing this timing wheel horizon in nsec units. This is a read-only attribute. Unless a driver sets it, dev->max_pacing_offload_horizon is zero. v2: addressed Jakub feedback ( https://lore.kernel.org/netdev/20240930152304.472767-2-edumazet@google.com/T/#mf6294d714c41cc459962154cc2580ce3c9693663 ) v3: added yaml doc (also per Jakub feedback) Signed-off-by: Eric Dumazet Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20241003121219.2396589-2-edumazet@google.com Signed-off-by: Jakub Kicinski --- include/linux/netdevice.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/linux') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 4d20c776a4ff..49a7e7db0883 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2009,6 +2009,8 @@ enum netdev_reg_state { * @dpll_pin: Pointer to the SyncE source pin of a DPLL subsystem, * where the clock is recovered. * + * @max_pacing_offload_horizon: max EDT offload horizon in nsec. + * * FIXME: cleanup struct net_device such that network protocol info * moves out. */ @@ -2399,6 +2401,8 @@ struct net_device { /** @irq_moder: dim parameters used if IS_ENABLED(CONFIG_DIMLIB). */ struct dim_irq_moder *irq_moder; + u64 max_pacing_offload_horizon; + u8 priv[] ____cacheline_aligned __counted_by(priv_len); } ____cacheline_aligned; -- cgit v1.2.3