[PATCH iwl-next] libeth, idpf: use GFP_KERNEL for the initial Rx ring fill
DORMANTno replies
From: Luigi Rizzo <hidden>
Date: 2026-10-16 15:37:46
Also in:
intel-wired-lan, lkml
Subsystem:
intel ethernet drivers, libeth common ethernet library, networking drivers, networking [general], the rest · Maintainers:
Tony Nguyen, Przemek Kitszel, Alexander Lobakin, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
libeth_rx_alloc() always allocates with GFP_ATOMIC, including when idpf fills its Rx rings at open or on queue reconfiguration. That fill runs in process context, right after page_pool_create() and before the queues' NAPI is enabled, so it may sleep, and GFP_ATOMIC is needlessly restrictive there: it can neither reclaim nor compact, while the initial fill can allocate tens of thousands of buffers across all queues. Add libeth_rx_alloc_gfp(), which takes the allocation flags, and make libeth_rx_alloc() its GFP_ATOMIC wrapper. Use GFP_KERNEL for the initial fill in idpf. Signed-off-by: Luigi Rizzo <redacted> --- .../ethernet/intel/idpf/idpf_singleq_txrx.c | 7 +++--- drivers/net/ethernet/intel/idpf/idpf_txrx.c | 9 +++++--- drivers/net/ethernet/intel/idpf/idpf_txrx.h | 2 +- include/net/libeth/rx.h | 23 +++++++++++++++---- 4 files changed, 30 insertions(+), 11 deletions(-)
diff --git a/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c
index e3ddf18dcbf51..d623e4ab8511f 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_singleq_txrx.c@@ -885,11 +885,12 @@ static void idpf_rx_buf_hw_update(struct idpf_rx_queue *rxq, u32 val) * idpf_rx_singleq_buf_hw_alloc_all - Replace used receive buffers * @rx_q: queue for which the hw buffers are allocated * @cleaned_count: number of buffers to replace + * @gfp: GFP_KERNEL for the initial fill, GFP_ATOMIC from NAPI * * Returns false if all allocations were successful, true if any fail */ bool idpf_rx_singleq_buf_hw_alloc_all(struct idpf_rx_queue *rx_q, - u16 cleaned_count) + u16 cleaned_count, gfp_t gfp) { struct virtchnl2_singleq_rx_buf_desc *desc; const struct libeth_fq_fp fq = {
@@ -908,7 +909,7 @@ bool idpf_rx_singleq_buf_hw_alloc_all(struct idpf_rx_queue *rx_q, do { dma_addr_t addr; - addr = libeth_rx_alloc(&fq, nta); + addr = libeth_rx_alloc_gfp(&fq, nta, gfp); if (addr == DMA_MAPPING_ERROR) break;
@@ -1095,7 +1096,7 @@ static int idpf_rx_singleq_clean(struct idpf_rx_queue *rx_q, int budget) page_pool_nid_changed(rx_q->pp, numa_mem_id()); if (cleaned_count) - idpf_rx_singleq_buf_hw_alloc_all(rx_q, cleaned_count); + idpf_rx_singleq_buf_hw_alloc_all(rx_q, cleaned_count, GFP_ATOMIC); u64_stats_update_begin(&rx_q->stats_sync); u64_stats_add(&rx_q->q_stats.packets, rs.packets);
diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
index 4311ffa30bb18..b1127ab48ef3f 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c@@ -600,6 +600,9 @@ static void idpf_post_buf_refill(struct idpf_sw_queue *refillq, u16 buf_id) * @bufq: buffer queue to post to * @buf_id: buffer id to post * + * Only used for the initial fill, from process context, so it allocates + * with GFP_KERNEL. + * * Return: %false if buffer could not be allocated, %true otherwise. */ static bool idpf_rx_post_buf_desc(struct idpf_buf_queue *bufq, u16 buf_id)
@@ -618,7 +621,7 @@ static bool idpf_rx_post_buf_desc(struct idpf_buf_queue *bufq, u16 buf_id) fq.fqes = bufq->hdr_buf; fq.truesize = bufq->hdr_truesize; - addr = libeth_rx_alloc(&fq, buf_id); + addr = libeth_rx_alloc_gfp(&fq, buf_id, GFP_KERNEL); if (addr == DMA_MAPPING_ERROR) return false;
@@ -629,7 +632,7 @@ static bool idpf_rx_post_buf_desc(struct idpf_buf_queue *bufq, u16 buf_id) fq.fqes = bufq->buf; fq.truesize = bufq->truesize; - addr = libeth_rx_alloc(&fq, buf_id); + addr = libeth_rx_alloc_gfp(&fq, buf_id, GFP_KERNEL); if (addr == DMA_MAPPING_ERROR) return false;
@@ -675,7 +678,7 @@ static bool idpf_rx_post_init_bufs(struct idpf_buf_queue *bufq, */ static int idpf_rx_buf_alloc_singleq(struct idpf_rx_queue *rxq) { - if (idpf_rx_singleq_buf_hw_alloc_all(rxq, rxq->desc_count - 1)) + if (idpf_rx_singleq_buf_hw_alloc_all(rxq, rxq->desc_count - 1, GFP_KERNEL)) goto err; return 0;
diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.h b/drivers/net/ethernet/intel/idpf/idpf_txrx.h
index 93547597efd2a..e27438c78ec79 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.h
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.h@@ -1123,7 +1123,7 @@ netdev_tx_t idpf_tx_singleq_frame(struct sk_buff *skb, struct idpf_tx_queue *tx_q); netdev_tx_t idpf_tx_start(struct sk_buff *skb, struct net_device *netdev); bool idpf_rx_singleq_buf_hw_alloc_all(struct idpf_rx_queue *rxq, - u16 cleaned_count); + u16 cleaned_count, gfp_t gfp); bool idpf_rx_process_skb_fields(struct sk_buff *skb, const struct libeth_xdp_buff *xdp, struct libeth_rq_napi_stats *rs);
diff --git a/include/net/libeth/rx.h b/include/net/libeth/rx.h
index 0e736846c5e8a..14a528ea8a075 100644
--- a/include/net/libeth/rx.h
+++ b/include/net/libeth/rx.h@@ -96,20 +96,23 @@ int libeth_rx_fq_create(struct libeth_fq *fq, void *napi_dev); void libeth_rx_fq_destroy(struct libeth_fq *fq); /** - * libeth_rx_alloc - allocate a new Rx buffer + * libeth_rx_alloc_gfp - allocate a new Rx buffer * @fq: fill queue to allocate for * @i: index of the buffer within the queue + * @gfp: allocation flags: GFP_KERNEL where the caller may sleep (e.g. the + * initial fill of the ring), GFP_ATOMIC from NAPI * * Return: DMA address to be passed to HW for Rx on successful allocation, * ```DMA_MAPPING_ERROR``` otherwise. */ -static inline dma_addr_t libeth_rx_alloc(const struct libeth_fq_fp *fq, u32 i) +static inline dma_addr_t libeth_rx_alloc_gfp(const struct libeth_fq_fp *fq, + u32 i, gfp_t gfp) { struct libeth_fqe *buf = &fq->fqes[i]; buf->truesize = fq->truesize; - buf->netmem = page_pool_dev_alloc_netmem(fq->pp, &buf->offset, - &buf->truesize); + buf->netmem = page_pool_alloc_netmem(fq->pp, &buf->offset, + &buf->truesize, gfp | __GFP_NOWARN); if (unlikely(!buf->netmem)) return DMA_MAPPING_ERROR;
@@ -117,6 +120,18 @@ static inline dma_addr_t libeth_rx_alloc(const struct libeth_fq_fp *fq, u32 i) fq->pp->p.offset; } +/** + * libeth_rx_alloc - allocate a new Rx buffer from NAPI context + * @fq: fill queue to allocate for + * @i: index of the buffer within the queue + * + * Return: as libeth_rx_alloc_gfp(). + */ +static inline dma_addr_t libeth_rx_alloc(const struct libeth_fq_fp *fq, u32 i) +{ + return libeth_rx_alloc_gfp(fq, i, GFP_ATOMIC); +} + void libeth_rx_recycle_slow(netmem_ref netmem); /**
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2.56.0.176.g3575e65682-goog