From 02443ab8c9314134c9cd58946121726e4cd9a5c1 Mon Sep 17 00:00:00 2001 From: Edward Cree Date: Wed, 20 Jul 2022 19:33:47 +0100 Subject: sfc: support passing a representor to the EF100 TX path A non-null efv in __ef100_enqueue_skb() indicates that the packet is from that representor, should be transmitted with a suitable option descriptor (to instruct the switch to deliver it to the representee), and should not be accounted to the parent PF's stats or BQL. Signed-off-by: Edward Cree Signed-off-by: David S. Miller --- drivers/net/ethernet/sfc/ef100_rep.h | 8 ++++ drivers/net/ethernet/sfc/ef100_tx.c | 84 +++++++++++++++++++++++++++++++++-- drivers/net/ethernet/sfc/ef100_tx.h | 3 ++ drivers/net/ethernet/sfc/net_driver.h | 1 + drivers/net/ethernet/sfc/tx.c | 6 ++- drivers/net/ethernet/sfc/tx_common.c | 35 ++++++++++----- drivers/net/ethernet/sfc/tx_common.h | 3 +- 7 files changed, 123 insertions(+), 17 deletions(-) diff --git a/drivers/net/ethernet/sfc/ef100_rep.h b/drivers/net/ethernet/sfc/ef100_rep.h index 1d17aaf6cd5c..d47fd8ff6220 100644 --- a/drivers/net/ethernet/sfc/ef100_rep.h +++ b/drivers/net/ethernet/sfc/ef100_rep.h @@ -15,6 +15,12 @@ #include "net_driver.h" +struct efx_rep_sw_stats { + atomic64_t rx_packets, tx_packets; + atomic64_t rx_bytes, tx_bytes; + atomic64_t rx_dropped, tx_errors; +}; + /** * struct efx_rep - Private data for an Efx representor * @@ -24,6 +30,7 @@ * @mport: m-port ID of corresponding VF * @idx: VF index * @list: entry on efx->vf_reps + * @stats: software traffic counters for netdev stats */ struct efx_rep { struct efx_nic *parent; @@ -32,6 +39,7 @@ struct efx_rep { u32 mport; unsigned int idx; struct list_head list; + struct efx_rep_sw_stats stats; }; int efx_ef100_vfrep_create(struct efx_nic *efx, unsigned int i); diff --git a/drivers/net/ethernet/sfc/ef100_tx.c b/drivers/net/ethernet/sfc/ef100_tx.c index 26ef51d6b542..102ddc7e206a 100644 --- a/drivers/net/ethernet/sfc/ef100_tx.c +++ b/drivers/net/ethernet/sfc/ef100_tx.c @@ -254,7 +254,8 @@ static void ef100_make_tso_desc(struct efx_nic *efx, static void ef100_tx_make_descriptors(struct efx_tx_queue *tx_queue, const struct sk_buff *skb, - unsigned int segment_count) + unsigned int segment_count, + struct efx_rep *efv) { unsigned int old_write_count = tx_queue->write_count; unsigned int new_write_count = old_write_count; @@ -272,6 +273,20 @@ static void ef100_tx_make_descriptors(struct efx_tx_queue *tx_queue, else next_desc_type = ESE_GZ_TX_DESC_TYPE_SEND; + if (unlikely(efv)) { + /* Create TX override descriptor */ + write_ptr = new_write_count & tx_queue->ptr_mask; + txd = ef100_tx_desc(tx_queue, write_ptr); + ++new_write_count; + + tx_queue->packet_write_count = new_write_count; + EFX_POPULATE_OWORD_3(*txd, + ESF_GZ_TX_DESC_TYPE, ESE_GZ_TX_DESC_TYPE_PREFIX, + ESF_GZ_TX_PREFIX_EGRESS_MPORT, efv->mport, + ESF_GZ_TX_PREFIX_EGRESS_MPORT_EN, 1); + nr_descs--; + } + /* if it's a raw write (such as XDP) then always SEND single frames */ if (!skb) nr_descs = 1; @@ -306,6 +321,9 @@ static void ef100_tx_make_descriptors(struct efx_tx_queue *tx_queue, /* if it's a raw write (such as XDP) then always SEND */ next_desc_type = skb ? ESE_GZ_TX_DESC_TYPE_SEG : ESE_GZ_TX_DESC_TYPE_SEND; + /* mark as an EFV buffer if applicable */ + if (unlikely(efv)) + buffer->flags |= EFX_TX_BUF_EFV; } while (new_write_count != tx_queue->insert_count); @@ -324,7 +342,7 @@ static void ef100_tx_make_descriptors(struct efx_tx_queue *tx_queue, void ef100_tx_write(struct efx_tx_queue *tx_queue) { - ef100_tx_make_descriptors(tx_queue, NULL, 0); + ef100_tx_make_descriptors(tx_queue, NULL, 0, NULL); ef100_tx_push_buffers(tx_queue); } @@ -350,6 +368,12 @@ void ef100_ev_tx(struct efx_channel *channel, const efx_qword_t *p_event) * function will free the SKB. */ int ef100_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb) +{ + return __ef100_enqueue_skb(tx_queue, skb, NULL); +} + +int __ef100_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb, + struct efx_rep *efv) { unsigned int old_insert_count = tx_queue->insert_count; struct efx_nic *efx = tx_queue->efx; @@ -376,16 +400,64 @@ int ef100_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb) return 0; } + if (unlikely(efv)) { + struct efx_tx_buffer *buffer = __efx_tx_queue_get_insert_buffer(tx_queue); + + /* Drop representor packets if the queue is stopped. + * We currently don't assert backoff to representors so this is + * to make sure representor traffic can't starve the main + * net device. + * And, of course, if there are no TX descriptors left. + */ + if (netif_tx_queue_stopped(tx_queue->core_txq) || + unlikely(efx_tx_buffer_in_use(buffer))) { + atomic64_inc(&efv->stats.tx_errors); + rc = -ENOSPC; + goto err; + } + + /* Also drop representor traffic if it could cause us to + * stop the queue. If we assert backoff and we haven't + * received traffic on the main net device recently then the + * TX watchdog can go off erroneously. + */ + fill_level = efx_channel_tx_old_fill_level(tx_queue->channel); + fill_level += efx_tx_max_skb_descs(efx); + if (fill_level > efx->txq_stop_thresh) { + struct efx_tx_queue *txq2; + + /* Refresh cached fill level and re-check */ + efx_for_each_channel_tx_queue(txq2, tx_queue->channel) + txq2->old_read_count = READ_ONCE(txq2->read_count); + + fill_level = efx_channel_tx_old_fill_level(tx_queue->channel); + fill_level += efx_tx_max_skb_descs(efx); + if (fill_level > efx->txq_stop_thresh) { + atomic64_inc(&efv->stats.tx_errors); + rc = -ENOSPC; + goto err; + } + } + + buffer->flags = EFX_TX_BUF_OPTION | EFX_TX_BUF_EFV; + tx_queue->insert_count++; + } + /* Map for DMA and create descriptors */ rc = efx_tx_map_data(tx_queue, skb, segments); if (rc) goto err; - ef100_tx_make_descriptors(tx_queue, skb, segments); + ef100_tx_make_descriptors(tx_queue, skb, segments, efv); fill_level = efx_channel_tx_old_fill_level(tx_queue->channel); if (fill_level > efx->txq_stop_thresh) { struct efx_tx_queue *txq2; + /* Because of checks above, representor traffic should + * not be able to stop the queue. + */ + WARN_ON(efv); + netif_tx_stop_queue(tx_queue->core_txq); /* Re-read after a memory barrier in case we've raced with * the completion path. Otherwise there's a danger we'll never @@ -404,8 +476,12 @@ int ef100_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb) /* If xmit_more then we don't need to push the doorbell, unless there * are 256 descriptors already queued in which case we have to push to * ensure we never push more than 256 at once. + * + * Always push for representor traffic, and don't account it to parent + * PF netdevice's BQL. */ - if (__netdev_tx_sent_queue(tx_queue->core_txq, skb->len, xmit_more) || + if (unlikely(efv) || + __netdev_tx_sent_queue(tx_queue->core_txq, skb->len, xmit_more) || tx_queue->write_count - tx_queue->notify_count > 255) ef100_tx_push_buffers(tx_queue); diff --git a/drivers/net/ethernet/sfc/ef100_tx.h b/drivers/net/ethernet/sfc/ef100_tx.h index ddc4b98fa6db..e9e11540fcde 100644 --- a/drivers/net/ethernet/sfc/ef100_tx.h +++ b/drivers/net/ethernet/sfc/ef100_tx.h @@ -13,6 +13,7 @@ #define EFX_EF100_TX_H #include "net_driver.h" +#include "ef100_rep.h" int ef100_tx_probe(struct efx_tx_queue *tx_queue); void ef100_tx_init(struct efx_tx_queue *tx_queue); @@ -22,4 +23,6 @@ unsigned int ef100_tx_max_skb_descs(struct efx_nic *efx); void ef100_ev_tx(struct efx_channel *channel, const efx_qword_t *p_event); netdev_tx_t ef100_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb); +int __ef100_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb, + struct efx_rep *efv); #endif diff --git a/drivers/net/ethernet/sfc/net_driver.h b/drivers/net/ethernet/sfc/net_driver.h index 037cfa184764..4cde54cf77b9 100644 --- a/drivers/net/ethernet/sfc/net_driver.h +++ b/drivers/net/ethernet/sfc/net_driver.h @@ -178,6 +178,7 @@ struct efx_tx_buffer { #define EFX_TX_BUF_OPTION 0x10 /* empty buffer for option descriptor */ #define EFX_TX_BUF_XDP 0x20 /* buffer was sent with XDP */ #define EFX_TX_BUF_TSO_V3 0x40 /* empty buffer for a TSO_V3 descriptor */ +#define EFX_TX_BUF_EFV 0x100 /* buffer was sent from representor */ /** * struct efx_tx_queue - An Efx TX queue diff --git a/drivers/net/ethernet/sfc/tx.c b/drivers/net/ethernet/sfc/tx.c index 79cc0bb76321..d12474042c84 100644 --- a/drivers/net/ethernet/sfc/tx.c +++ b/drivers/net/ethernet/sfc/tx.c @@ -559,6 +559,7 @@ netdev_tx_t efx_hard_start_xmit(struct sk_buff *skb, void efx_xmit_done_single(struct efx_tx_queue *tx_queue) { unsigned int pkts_compl = 0, bytes_compl = 0; + unsigned int efv_pkts_compl = 0; unsigned int read_ptr; bool finished = false; @@ -580,7 +581,8 @@ void efx_xmit_done_single(struct efx_tx_queue *tx_queue) /* Need to check the flag before dequeueing. */ if (buffer->flags & EFX_TX_BUF_SKB) finished = true; - efx_dequeue_buffer(tx_queue, buffer, &pkts_compl, &bytes_compl); + efx_dequeue_buffer(tx_queue, buffer, &pkts_compl, &bytes_compl, + &efv_pkts_compl); ++tx_queue->read_count; read_ptr = tx_queue->read_count & tx_queue->ptr_mask; @@ -589,7 +591,7 @@ void efx_xmit_done_single(struct efx_tx_queue *tx_queue) tx_queue->pkts_compl += pkts_compl; tx_queue->bytes_compl += bytes_compl; - EFX_WARN_ON_PARANOID(pkts_compl != 1); + EFX_WARN_ON_PARANOID(pkts_compl + efv_pkts_compl != 1); efx_xmit_done_check_empty(tx_queue); } diff --git a/drivers/net/ethernet/sfc/tx_common.c b/drivers/net/ethernet/sfc/tx_common.c index 658ea2d34070..67e789b96c43 100644 --- a/drivers/net/ethernet/sfc/tx_common.c +++ b/drivers/net/ethernet/sfc/tx_common.c @@ -109,9 +109,11 @@ void efx_fini_tx_queue(struct efx_tx_queue *tx_queue) /* Free any buffers left in the ring */ while (tx_queue->read_count != tx_queue->write_count) { unsigned int pkts_compl = 0, bytes_compl = 0; + unsigned int efv_pkts_compl = 0; buffer = &tx_queue->buffer[tx_queue->read_count & tx_queue->ptr_mask]; - efx_dequeue_buffer(tx_queue, buffer, &pkts_compl, &bytes_compl); + efx_dequeue_buffer(tx_queue, buffer, &pkts_compl, &bytes_compl, + &efv_pkts_compl); ++tx_queue->read_count; } @@ -146,7 +148,8 @@ void efx_remove_tx_queue(struct efx_tx_queue *tx_queue) void efx_dequeue_buffer(struct efx_tx_queue *tx_queue, struct efx_tx_buffer *buffer, unsigned int *pkts_compl, - unsigned int *bytes_compl) + unsigned int *bytes_compl, + unsigned int *efv_pkts_compl) { if (buffer->unmap_len) { struct device *dma_dev = &tx_queue->efx->pci_dev->dev; @@ -164,9 +167,15 @@ void efx_dequeue_buffer(struct efx_tx_queue *tx_queue, if (buffer->flags & EFX_TX_BUF_SKB) { struct sk_buff *skb = (struct sk_buff *)buffer->skb; - EFX_WARN_ON_PARANOID(!pkts_compl || !bytes_compl); - (*pkts_compl)++; - (*bytes_compl) += skb->len; + if (unlikely(buffer->flags & EFX_TX_BUF_EFV)) { + EFX_WARN_ON_PARANOID(!efv_pkts_compl); + (*efv_pkts_compl)++; + } else { + EFX_WARN_ON_PARANOID(!pkts_compl || !bytes_compl); + (*pkts_compl)++; + (*bytes_compl) += skb->len; + } + if (tx_queue->timestamping && (tx_queue->completed_timestamp_major || tx_queue->completed_timestamp_minor)) { @@ -199,7 +208,8 @@ void efx_dequeue_buffer(struct efx_tx_queue *tx_queue, static void efx_dequeue_buffers(struct efx_tx_queue *tx_queue, unsigned int index, unsigned int *pkts_compl, - unsigned int *bytes_compl) + unsigned int *bytes_compl, + unsigned int *efv_pkts_compl) { struct efx_nic *efx = tx_queue->efx; unsigned int stop_index, read_ptr; @@ -218,7 +228,8 @@ static void efx_dequeue_buffers(struct efx_tx_queue *tx_queue, return; } - efx_dequeue_buffer(tx_queue, buffer, pkts_compl, bytes_compl); + efx_dequeue_buffer(tx_queue, buffer, pkts_compl, bytes_compl, + efv_pkts_compl); ++tx_queue->read_count; read_ptr = tx_queue->read_count & tx_queue->ptr_mask; @@ -241,15 +252,17 @@ void efx_xmit_done_check_empty(struct efx_tx_queue *tx_queue) void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index) { unsigned int fill_level, pkts_compl = 0, bytes_compl = 0; + unsigned int efv_pkts_compl = 0; struct efx_nic *efx = tx_queue->efx; EFX_WARN_ON_ONCE_PARANOID(index > tx_queue->ptr_mask); - efx_dequeue_buffers(tx_queue, index, &pkts_compl, &bytes_compl); + efx_dequeue_buffers(tx_queue, index, &pkts_compl, &bytes_compl, + &efv_pkts_compl); tx_queue->pkts_compl += pkts_compl; tx_queue->bytes_compl += bytes_compl; - if (pkts_compl > 1) + if (pkts_compl + efv_pkts_compl > 1) ++tx_queue->merge_events; /* See if we need to restart the netif queue. This memory @@ -274,6 +287,7 @@ void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index) void efx_enqueue_unwind(struct efx_tx_queue *tx_queue, unsigned int insert_count) { + unsigned int efv_pkts_compl = 0; struct efx_tx_buffer *buffer; unsigned int bytes_compl = 0; unsigned int pkts_compl = 0; @@ -282,7 +296,8 @@ void efx_enqueue_unwind(struct efx_tx_queue *tx_queue, while (tx_queue->insert_count != insert_count) { --tx_queue->insert_count; buffer = __efx_tx_queue_get_insert_buffer(tx_queue); - efx_dequeue_buffer(tx_queue, buffer, &pkts_compl, &bytes_compl); + efx_dequeue_buffer(tx_queue, buffer, &pkts_compl, &bytes_compl, + &efv_pkts_compl); } } diff --git a/drivers/net/ethernet/sfc/tx_common.h b/drivers/net/ethernet/sfc/tx_common.h index bbab7f248250..d87aecbc7bf1 100644 --- a/drivers/net/ethernet/sfc/tx_common.h +++ b/drivers/net/ethernet/sfc/tx_common.h @@ -19,7 +19,8 @@ void efx_remove_tx_queue(struct efx_tx_queue *tx_queue); void efx_dequeue_buffer(struct efx_tx_queue *tx_queue, struct efx_tx_buffer *buffer, unsigned int *pkts_compl, - unsigned int *bytes_compl); + unsigned int *bytes_compl, + unsigned int *efv_pkts_compl); static inline bool efx_tx_buffer_in_use(struct efx_tx_buffer *buffer) { -- cgit v1.2.3