From 306ec721d043bbe5e818d59fbb37c28d999b5d8b Mon Sep 17 00:00:00 2001 From: Alexander Lobakin Date: Thu, 18 Apr 2024 13:36:07 +0200 Subject: net: intel: introduce {, Intel} Ethernet common library Not a secret there's a ton of code duplication between two and more Intel ethernet modules. Before introducing new changes, which would need to be copied over again, start decoupling the already existing duplicate functionality into a new module, which will be shared between several Intel Ethernet drivers. Add the lookup table which converts 8/10-bit hardware packet type into a parsed bitfield structure for easy checking packet format parameters, such as payload level, IP version, etc. This is currently used by i40e, ice and iavf and it's all the same in all three drivers. The only difference introduced in this implementation is that instead of defining a 256 (or 1024 in case of ice) element array, add unlikely() condition to limit the input to 154 (current maximum non-reserved packet type). There's no reason to waste 600 (or even 3600) bytes only to not hurt very unlikely exception packets. The hash computation function now takes payload level directly as a pkt_hash_type. There's a couple cases when non-IP ptypes are marked as L3 payload and in the previous versions their hash level would be 2, not 3. But skb_set_hash() only sees difference between L4 and non-L4, thus this won't change anything at all. The module is behind the hidden Kconfig symbol, which the drivers will select when needed. The exports are behind 'LIBIE' namespace to limit the scope of the functions. Not that non-HW-specific symbols will live in yet another module, libeth. This is done to easily distinguish pretty generic code ready for reusing by any other vendor and/or for moving the layer up from the code useful in Intel's 1-100G drivers only. Signed-off-by: Alexander Lobakin Signed-off-by: Tony Nguyen --- include/linux/net/intel/libie/rx.h | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) create mode 100644 include/linux/net/intel/libie/rx.h (limited to 'include/linux/net/intel') diff --git a/include/linux/net/intel/libie/rx.h b/include/linux/net/intel/libie/rx.h new file mode 100644 index 000000000000..37c5c8f26fb9 --- /dev/null +++ b/include/linux/net/intel/libie/rx.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* Copyright (C) 2024 Intel Corporation */ + +#ifndef __LIBIE_RX_H +#define __LIBIE_RX_H + +#include + +/* O(1) converting i40e/ice/iavf's 8/10-bit hardware packet type to a parsed + * bitfield struct. + */ + +#define LIBIE_RX_PT_NUM 154 + +extern const struct libeth_rx_pt libie_rx_pt_lut[LIBIE_RX_PT_NUM]; + +/** + * libie_rx_pt_parse - convert HW packet type to software bitfield structure + * @pt: 10-bit hardware packet type value from the descriptor + * + * ```libie_rx_pt_lut``` must be accessed only using this wrapper. + * + * Return: parsed bitfield struct corresponding to the provided ptype. + */ +static inline struct libeth_rx_pt libie_rx_pt_parse(u32 pt) +{ + if (unlikely(pt >= LIBIE_RX_PT_NUM)) + pt = 0; + + return libie_rx_pt_lut[pt]; +} + +#endif /* __LIBIE_RX_H */ -- cgit v1.2.3 From 5fa4caff59f251bf9f766fc48c9f0a774a9216a0 Mon Sep 17 00:00:00 2001 From: Alexander Lobakin Date: Thu, 18 Apr 2024 13:36:15 +0200 Subject: iavf: switch to Page Pool Now that the IAVF driver simply uses dev_alloc_page() + free_page() with no custom recycling logics, it can easily be switched to using Page Pool / libeth API instead. This allows to removing the whole dancing around headroom, HW buffer size, and page order. All DMA-for-device is now done in the PP core, for-CPU -- in the libeth helper. Use skb_mark_for_recycle() to bring back the recycling and restore the performance. Speaking of performance: on par with the baseline and faster with the PP optimization series applied. But the memory usage for 1500b MTU is now almost 2x lower (x86_64) thanks to allocating a page every second descriptor. Signed-off-by: Alexander Lobakin Signed-off-by: Tony Nguyen --- include/linux/net/intel/libie/rx.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'include/linux/net/intel') diff --git a/include/linux/net/intel/libie/rx.h b/include/linux/net/intel/libie/rx.h index 37c5c8f26fb9..8e97775f1d66 100644 --- a/include/linux/net/intel/libie/rx.h +++ b/include/linux/net/intel/libie/rx.h @@ -6,6 +6,23 @@ #include +/* Rx buffer management */ + +/* The largest size for a single descriptor as per HW */ +#define LIBIE_MAX_RX_BUF_LEN 9728U +/* "True" HW-writeable space: minimum from SW and HW values */ +#define LIBIE_RX_BUF_LEN(hr) min_t(u32, LIBETH_RX_PAGE_LEN(hr), \ + LIBIE_MAX_RX_BUF_LEN) + +/* The maximum frame size as per HW (S/G) */ +#define __LIBIE_MAX_RX_FRM_LEN 16382U +/* ATST, HW can chain up to 5 Rx descriptors */ +#define LIBIE_MAX_RX_FRM_LEN(hr) \ + min_t(u32, __LIBIE_MAX_RX_FRM_LEN, LIBIE_RX_BUF_LEN(hr) * 5) +/* Maximum frame size minus LL overhead */ +#define LIBIE_MAX_MTU \ + (LIBIE_MAX_RX_FRM_LEN(LIBETH_MAX_HEADROOM) - LIBETH_RX_LL_LEN) + /* O(1) converting i40e/ice/iavf's 8/10-bit hardware packet type to a parsed * bitfield struct. */ -- cgit v1.2.3