From 6ad5ff6e7282d1252364cc08af88260ef0ec4cda Mon Sep 17 00:00:00 2001 From: Alexander Lobakin Date: Thu, 12 Jun 2025 18:02:19 +0200 Subject: [PATCH] libeth: convert to netmem Back when the libeth Rx core was initially written, devmem was a draft and netmem_ref didn't exist in the mainline. Now that it's here, make libeth MP-agnostic before introducing any new code or any new library users. When it's known that the created PP/FQ is for header buffers, use faster "unsafe" underscored netmem <--> virt accessors as netmem_is_net_iov() is always false in that case, but consumes some cycles (bit test + true branch). Reviewed-by: Mina Almasry Signed-off-by: Alexander Lobakin Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/iavf/iavf_txrx.c | 14 ++++---- .../ethernet/intel/idpf/idpf_singleq_txrx.c | 2 +- drivers/net/ethernet/intel/idpf/idpf_txrx.c | 36 +++++++++++-------- drivers/net/ethernet/intel/libeth/rx.c | 8 ++--- include/net/libeth/rx.h | 22 ++++++------ 5 files changed, 46 insertions(+), 36 deletions(-) diff --git a/drivers/net/ethernet/intel/iavf/iavf_txrx.c b/drivers/net/ethernet/intel/iavf/iavf_txrx.c index 23e786b9793d3..aaf70c6256556 100644 --- a/drivers/net/ethernet/intel/iavf/iavf_txrx.c +++ b/drivers/net/ethernet/intel/iavf/iavf_txrx.c @@ -723,7 +723,7 @@ static void iavf_clean_rx_ring(struct iavf_ring *rx_ring) for (u32 i = rx_ring->next_to_clean; i != rx_ring->next_to_use; ) { const struct libeth_fqe *rx_fqes = &rx_ring->rx_fqes[i]; - page_pool_put_full_page(rx_ring->pp, rx_fqes->page, false); + libeth_rx_recycle_slow(rx_fqes->netmem); if (unlikely(++i == rx_ring->count)) i = 0; @@ -1197,10 +1197,11 @@ static void iavf_add_rx_frag(struct sk_buff *skb, const struct libeth_fqe *rx_buffer, unsigned int size) { - u32 hr = rx_buffer->page->pp->p.offset; + u32 hr = netmem_get_pp(rx_buffer->netmem)->p.offset; - skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buffer->page, - rx_buffer->offset + hr, size, rx_buffer->truesize); + skb_add_rx_frag_netmem(skb, skb_shinfo(skb)->nr_frags, + rx_buffer->netmem, rx_buffer->offset + hr, + size, rx_buffer->truesize); } /** @@ -1214,12 +1215,13 @@ static void iavf_add_rx_frag(struct sk_buff *skb, static struct sk_buff *iavf_build_skb(const struct libeth_fqe *rx_buffer, unsigned int size) { - u32 hr = rx_buffer->page->pp->p.offset; + struct page *buf_page = __netmem_to_page(rx_buffer->netmem); + u32 hr = buf_page->pp->p.offset; struct sk_buff *skb; void *va; /* prefetch first cache line of first page */ - va = page_address(rx_buffer->page) + rx_buffer->offset; + va = page_address(buf_page) + rx_buffer->offset; net_prefetch(va + hr); /* build an skb around the page buffer */ diff --git a/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c index 993c354aa27ad..555879b1248d8 100644 --- a/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c +++ b/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c @@ -1006,7 +1006,7 @@ static int idpf_rx_singleq_clean(struct idpf_rx_queue *rx_q, int budget) break; skip_data: - rx_buf->page = NULL; + rx_buf->netmem = 0; IDPF_SINGLEQ_BUMP_RING_IDX(rx_q, ntc); cleaned_count++; diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c index 5cf440e09d0a6..cef9dfb877e8d 100644 --- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c +++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c @@ -383,12 +383,12 @@ err_out: */ static void idpf_rx_page_rel(struct libeth_fqe *rx_buf) { - if (unlikely(!rx_buf->page)) + if (unlikely(!rx_buf->netmem)) return; - page_pool_put_full_page(rx_buf->page->pp, rx_buf->page, false); + libeth_rx_recycle_slow(rx_buf->netmem); - rx_buf->page = NULL; + rx_buf->netmem = 0; rx_buf->offset = 0; } @@ -3240,10 +3240,10 @@ idpf_rx_process_skb_fields(struct idpf_rx_queue *rxq, struct sk_buff *skb, void idpf_rx_add_frag(struct idpf_rx_buf *rx_buf, struct sk_buff *skb, unsigned int size) { - u32 hr = rx_buf->page->pp->p.offset; + u32 hr = netmem_get_pp(rx_buf->netmem)->p.offset; - skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buf->page, - rx_buf->offset + hr, size, rx_buf->truesize); + skb_add_rx_frag_netmem(skb, skb_shinfo(skb)->nr_frags, rx_buf->netmem, + rx_buf->offset + hr, size, rx_buf->truesize); } /** @@ -3266,16 +3266,20 @@ static u32 idpf_rx_hsplit_wa(const struct libeth_fqe *hdr, struct libeth_fqe *buf, u32 data_len) { u32 copy = data_len <= L1_CACHE_BYTES ? data_len : ETH_HLEN; + struct page *hdr_page, *buf_page; const void *src; void *dst; - if (!libeth_rx_sync_for_cpu(buf, copy)) + if (unlikely(netmem_is_net_iov(buf->netmem)) || + !libeth_rx_sync_for_cpu(buf, copy)) return 0; - dst = page_address(hdr->page) + hdr->offset + hdr->page->pp->p.offset; - src = page_address(buf->page) + buf->offset + buf->page->pp->p.offset; - memcpy(dst, src, LARGEST_ALIGN(copy)); + hdr_page = __netmem_to_page(hdr->netmem); + buf_page = __netmem_to_page(buf->netmem); + dst = page_address(hdr_page) + hdr->offset + hdr_page->pp->p.offset; + src = page_address(buf_page) + buf->offset + buf_page->pp->p.offset; + memcpy(dst, src, LARGEST_ALIGN(copy)); buf->offset += copy; return copy; @@ -3291,11 +3295,12 @@ static u32 idpf_rx_hsplit_wa(const struct libeth_fqe *hdr, */ struct sk_buff *idpf_rx_build_skb(const struct libeth_fqe *buf, u32 size) { - u32 hr = buf->page->pp->p.offset; + struct page *buf_page = __netmem_to_page(buf->netmem); + u32 hr = buf_page->pp->p.offset; struct sk_buff *skb; void *va; - va = page_address(buf->page) + buf->offset; + va = page_address(buf_page) + buf->offset; prefetch(va + hr); skb = napi_build_skb(va, buf->truesize); @@ -3429,7 +3434,8 @@ static int idpf_rx_splitq_clean(struct idpf_rx_queue *rxq, int budget) if (unlikely(!hdr_len && !skb)) { hdr_len = idpf_rx_hsplit_wa(hdr, rx_buf, pkt_len); - pkt_len -= hdr_len; + /* If failed, drop both buffers by setting len to 0 */ + pkt_len -= hdr_len ? : pkt_len; u64_stats_update_begin(&rxq->stats_sync); u64_stats_inc(&rxq->q_stats.hsplit_buf_ovf); @@ -3446,7 +3452,7 @@ static int idpf_rx_splitq_clean(struct idpf_rx_queue *rxq, int budget) u64_stats_update_end(&rxq->stats_sync); } - hdr->page = NULL; + hdr->netmem = 0; payload: if (!libeth_rx_sync_for_cpu(rx_buf, pkt_len)) @@ -3462,7 +3468,7 @@ payload: break; skip_data: - rx_buf->page = NULL; + rx_buf->netmem = 0; idpf_rx_post_buf_refill(refillq, buf_id); IDPF_RX_BUMP_NTC(rxq, ntc); diff --git a/drivers/net/ethernet/intel/libeth/rx.c b/drivers/net/ethernet/intel/libeth/rx.c index c2c53552c4403..2afa6e33f1609 100644 --- a/drivers/net/ethernet/intel/libeth/rx.c +++ b/drivers/net/ethernet/intel/libeth/rx.c @@ -204,14 +204,14 @@ void libeth_rx_fq_destroy(struct libeth_fq *fq) EXPORT_SYMBOL_GPL(libeth_rx_fq_destroy); /** - * libeth_rx_recycle_slow - recycle a libeth page from the NAPI context - * @page: page to recycle + * libeth_rx_recycle_slow - recycle libeth netmem + * @netmem: network memory to recycle * * To be used on exceptions or rare cases not requiring fast inline recycling. */ -void libeth_rx_recycle_slow(struct page *page) +void __cold libeth_rx_recycle_slow(netmem_ref netmem) { - page_pool_recycle_direct(page->pp, page); + page_pool_put_full_netmem(netmem_get_pp(netmem), netmem, false); } EXPORT_SYMBOL_GPL(libeth_rx_recycle_slow); diff --git a/include/net/libeth/rx.h b/include/net/libeth/rx.h index ab05024be5186..7d5dc58984b18 100644 --- a/include/net/libeth/rx.h +++ b/include/net/libeth/rx.h @@ -1,5 +1,5 @@ /* SPDX-License-Identifier: GPL-2.0-only */ -/* Copyright (C) 2024 Intel Corporation */ +/* Copyright (C) 2024-2025 Intel Corporation */ #ifndef __LIBETH_RX_H #define __LIBETH_RX_H @@ -31,7 +31,7 @@ /** * struct libeth_fqe - structure representing an Rx buffer (fill queue element) - * @page: page holding the buffer + * @netmem: network memory reference holding the buffer * @offset: offset from the page start (to the headroom) * @truesize: total space occupied by the buffer (w/ headroom and tailroom) * @@ -40,7 +40,7 @@ * former, @offset is always 0 and @truesize is always ```PAGE_SIZE```. */ struct libeth_fqe { - struct page *page; + netmem_ref netmem; u32 offset; u32 truesize; } __aligned_largest; @@ -102,15 +102,16 @@ static inline dma_addr_t libeth_rx_alloc(const struct libeth_fq_fp *fq, u32 i) struct libeth_fqe *buf = &fq->fqes[i]; buf->truesize = fq->truesize; - buf->page = page_pool_dev_alloc(fq->pp, &buf->offset, &buf->truesize); - if (unlikely(!buf->page)) + buf->netmem = page_pool_dev_alloc_netmem(fq->pp, &buf->offset, + &buf->truesize); + if (unlikely(!buf->netmem)) return DMA_MAPPING_ERROR; - return page_pool_get_dma_addr(buf->page) + buf->offset + + return page_pool_get_dma_addr_netmem(buf->netmem) + buf->offset + fq->pp->p.offset; } -void libeth_rx_recycle_slow(struct page *page); +void libeth_rx_recycle_slow(netmem_ref netmem); /** * libeth_rx_sync_for_cpu - synchronize or recycle buffer post DMA @@ -126,18 +127,19 @@ void libeth_rx_recycle_slow(struct page *page); static inline bool libeth_rx_sync_for_cpu(const struct libeth_fqe *fqe, u32 len) { - struct page *page = fqe->page; + netmem_ref netmem = fqe->netmem; /* Very rare, but possible case. The most common reason: * the last fragment contained FCS only, which was then * stripped by the HW. */ if (unlikely(!len)) { - libeth_rx_recycle_slow(page); + libeth_rx_recycle_slow(netmem); return false; } - page_pool_dma_sync_for_cpu(page->pp, page, fqe->offset, len); + page_pool_dma_sync_netmem_for_cpu(netmem_get_pp(netmem), netmem, + fqe->offset, len); return true; } -- 2.47.2