| Message ID | 20240325204740.1393349-1-ast@fiberby.net (mailing list archive) |
|---|---|
| Headers | show |
| Series | make skip_sw actually skip software | expand |
Hello: This series was applied to netdev/net-next.git (main) by David S. Miller <davem@davemloft.net>: On Mon, 25 Mar 2024 20:47:33 +0000 you wrote: > Hi, > > During development of flower-route[1], which I > recently presented at FOSDEM[2], I noticed that > CPU usage, would increase the more rules I installed > into the hardware for IP forwarding offloading. > > [...] Here is the summary with links: - [net-next,v4,1/3] net: sched: cls_api: add skip_sw counter https://git.kernel.org/netdev/net-next/c/f631ef39d819 - [net-next,v4,2/3] net: sched: cls_api: add filter counter https://git.kernel.org/netdev/net-next/c/2081fd3445fe - [net-next,v4,3/3] net: sched: make skip_sw actually skip software https://git.kernel.org/netdev/net-next/c/047f340b36fc You are awesome, thank you!
Hi, During development of flower-route[1], which I recently presented at FOSDEM[2], I noticed that CPU usage, would increase the more rules I installed into the hardware for IP forwarding offloading. Since we use TC flower offload for the hottest prefixes, and leave the long tail to the normal (non-TC) Linux network stack for slow-path IP forwarding. We therefore need both the hardware and software datapath to perform well. I found that skip_sw rules, are quite expensive in the kernel datapath, since they must be evaluated and matched upon, before the kernel checks the skip_sw flag. This patchset optimizes the case where all rules are skip_sw, by implementing a TC bypass for these cases, where TC is only used as a control plane for the hardware path. v4: - Rebased onto net-next, now that net-next is open again v3: https://lore.kernel.org/netdev/20240306165813.656931-1-ast@fiberby.net/ - Patch 3: - Fix source_inline - Fix build failure, when CONFIG_NET_CLS without CONFIG_NET_CLS_ACT. v2: https://lore.kernel.org/netdev/20240305144404.569632-1-ast@fiberby.net/ - Patch 1: - Add Reviewed-By from Jiri Pirko - Patch 2: - Move code, to avoid forward declaration (Jiri). - Patch 3 - Refactor to use a static key. - Add performance data for trapping, or sending a packet to a non-existent chain (as suggested by Marcelo). v1: https://lore.kernel.org/netdev/20240215160458.1727237-1-ast@fiberby.net/ [1] flower-route https://github.com/fiberby-dk/flower-route [2] FOSDEM talk https://fosdem.org/2024/schedule/event/fosdem-2024-3337-flying-higher-hardware-offloading-with-bird/ Asbjørn Sloth Tønnesen (3): net: sched: cls_api: add skip_sw counter net: sched: cls_api: add filter counter net: sched: make skip_sw actually skip software include/net/pkt_cls.h | 9 +++++++++ include/net/sch_generic.h | 4 ++++ net/core/dev.c | 10 ++++++++++ net/sched/cls_api.c | 41 +++++++++++++++++++++++++++++++++++++++ 4 files changed, 64 insertions(+)