From: Alexander Lobakin <aleksander.lobakin@intel.com>
To: "David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>
Cc: Alexander Lobakin <aleksander.lobakin@intel.com>,
Maciej Fijalkowski <maciej.fijalkowski@intel.com>,
Michal Kubiak <michal.kubiak@intel.com>,
Larysa Zaremba <larysa.zaremba@intel.com>,
Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH RFC net-next 20/34] idpf: make complq cleaning dependent on scheduling mode
Date: Sat, 23 Dec 2023 03:55:40 +0100 [thread overview]
Message-ID: <20231223025554.2316836-21-aleksander.lobakin@intel.com> (raw)
In-Reply-To: <20231223025554.2316836-1-aleksander.lobakin@intel.com>
From: Michal Kubiak <michal.kubiak@intel.com>
Extend completion queue cleaning function to support queue-based
scheduling mode needed for XDP queues.
Add 4-byte descriptor for queue-based scheduling mode and
perform some refactoring to extract the common code for
both scheduling modes.
Make the completion desc parsing function a static inline, as
we'll need it in a different file soon.
Signed-off-by: Michal Kubiak <michal.kubiak@intel.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
---
.../net/ethernet/intel/idpf/idpf_lan_txrx.h | 6 +-
drivers/net/ethernet/intel/idpf/idpf_txrx.c | 203 ++++++++++--------
drivers/net/ethernet/intel/idpf/idpf_txrx.h | 44 ++++
3 files changed, 166 insertions(+), 87 deletions(-)
diff --git a/drivers/net/ethernet/intel/idpf/idpf_lan_txrx.h b/drivers/net/ethernet/intel/idpf/idpf_lan_txrx.h
index a5752dcab888..7f8fc9b61e90 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_lan_txrx.h
+++ b/drivers/net/ethernet/intel/idpf/idpf_lan_txrx.h
@@ -184,13 +184,17 @@ struct idpf_base_tx_desc {
__le64 qw1; /* type_cmd_offset_bsz_l2tag1 */
}; /* read used with buffer queues */
-struct idpf_splitq_tx_compl_desc {
+struct idpf_splitq_4b_tx_compl_desc {
/* qid=[10:0] comptype=[13:11] rsvd=[14] gen=[15] */
__le16 qid_comptype_gen;
union {
__le16 q_head; /* Queue head */
__le16 compl_tag; /* Completion tag */
} q_head_compl_tag;
+}; /* writeback used with completion queues */
+
+struct idpf_splitq_tx_compl_desc {
+ struct idpf_splitq_4b_tx_compl_desc common;
u8 ts[3];
u8 rsvd; /* Reserved */
}; /* writeback used with completion queues */
diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
index 40b8d8b17827..1a79ec1fb838 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
@@ -1722,8 +1722,8 @@ static bool idpf_tx_clean_buf_ring(struct idpf_queue *txq, u16 compl_tag,
}
/**
- * idpf_tx_handle_rs_completion - clean a single packet and all of its buffers
- * whether on the buffer ring or in the hash table
+ * idpf_tx_handle_rs_cmpl_qb - clean a single packet and all of its buffers
+ * whether the Tx queue is working in queue-based scheduling
* @txq: Tx ring to clean
* @desc: pointer to completion queue descriptor to extract completion
* information from
@@ -1732,20 +1732,33 @@ static bool idpf_tx_clean_buf_ring(struct idpf_queue *txq, u16 compl_tag,
*
* Returns bytes/packets cleaned
*/
-static void idpf_tx_handle_rs_completion(struct idpf_queue *txq,
- struct idpf_splitq_tx_compl_desc *desc,
- struct idpf_cleaned_stats *cleaned,
- int budget)
+static void
+idpf_tx_handle_rs_cmpl_qb(struct idpf_queue *txq,
+ const struct idpf_splitq_4b_tx_compl_desc *desc,
+ struct idpf_cleaned_stats *cleaned, int budget)
{
- u16 compl_tag;
+ u16 head = le16_to_cpu(desc->q_head_compl_tag.q_head);
- if (!test_bit(__IDPF_Q_FLOW_SCH_EN, txq->flags)) {
- u16 head = le16_to_cpu(desc->q_head_compl_tag.q_head);
-
- return idpf_tx_splitq_clean(txq, head, budget, cleaned, false);
- }
+ return idpf_tx_splitq_clean(txq, head, budget, cleaned, false);
+}
- compl_tag = le16_to_cpu(desc->q_head_compl_tag.compl_tag);
+/**
+ * idpf_tx_handle_rs_cmpl_fb - clean a single packet and all of its buffers
+ * whether on the buffer ring or in the hash table (flow-based scheduling only)
+ * @txq: Tx ring to clean
+ * @desc: pointer to completion queue descriptor to extract completion
+ * information from
+ * @cleaned: pointer to stats struct to track cleaned packets/bytes
+ * @budget: Used to determine if we are in netpoll
+ *
+ * Returns bytes/packets cleaned
+ */
+static void
+idpf_tx_handle_rs_cmpl_fb(struct idpf_queue *txq,
+ const struct idpf_splitq_4b_tx_compl_desc *desc,
+ struct idpf_cleaned_stats *cleaned,int budget)
+{
+ u16 compl_tag = le16_to_cpu(desc->q_head_compl_tag.compl_tag);
/* If we didn't clean anything on the ring, this packet must be
* in the hash table. Go clean it there.
@@ -1754,6 +1767,65 @@ static void idpf_tx_handle_rs_completion(struct idpf_queue *txq,
idpf_tx_clean_stashed_bufs(txq, compl_tag, cleaned, budget);
}
+/**
+ * idpf_tx_finalize_complq - Finalize completion queue cleaning
+ * @complq: completion queue to finalize
+ * @ntc: next to complete index
+ * @gen_flag: current state of generation flag
+ * @cleaned: returns number of packets cleaned
+ */
+static void idpf_tx_finalize_complq(struct idpf_queue *complq, int ntc,
+ bool gen_flag, int *cleaned)
+{
+ struct idpf_netdev_priv *np;
+ bool complq_ok = true;
+ int i;
+
+ /* Store the state of the complq to be used later in deciding if a
+ * TXQ can be started again
+ */
+ if (unlikely(IDPF_TX_COMPLQ_PENDING(complq->txq_grp) >
+ IDPF_TX_COMPLQ_OVERFLOW_THRESH(complq)))
+ complq_ok = false;
+
+ np = netdev_priv(complq->vport->netdev);
+ for (i = 0; i < complq->txq_grp->num_txq; ++i) {
+ struct idpf_queue *tx_q = complq->txq_grp->txqs[i];
+ struct netdev_queue *nq;
+ bool dont_wake;
+
+ /* We didn't clean anything on this queue, move along */
+ if (!tx_q->cleaned_bytes)
+ continue;
+
+ *cleaned += tx_q->cleaned_pkts;
+
+ /* Update BQL */
+ nq = netdev_get_tx_queue(tx_q->vport->netdev, tx_q->idx);
+
+ dont_wake = !complq_ok || IDPF_TX_BUF_RSV_LOW(tx_q) ||
+ np->state != __IDPF_VPORT_UP ||
+ !netif_carrier_ok(tx_q->vport->netdev);
+ /* Check if the TXQ needs to and can be restarted */
+ __netif_txq_completed_wake(nq, tx_q->cleaned_pkts, tx_q->cleaned_bytes,
+ IDPF_DESC_UNUSED(tx_q), IDPF_TX_WAKE_THRESH,
+ dont_wake);
+
+ /* Reset cleaned stats for the next time this queue is
+ * cleaned
+ */
+ tx_q->cleaned_bytes = 0;
+ tx_q->cleaned_pkts = 0;
+ }
+
+ ntc += complq->desc_count;
+ complq->next_to_clean = ntc;
+ if (gen_flag)
+ set_bit(__IDPF_Q_GEN_CHK, complq->flags);
+ else
+ clear_bit(__IDPF_Q_GEN_CHK, complq->flags);
+}
+
/**
* idpf_tx_clean_complq - Reclaim resources on completion queue
* @complq: Tx ring to clean
@@ -1765,61 +1837,55 @@ static void idpf_tx_handle_rs_completion(struct idpf_queue *txq,
static bool idpf_tx_clean_complq(struct idpf_queue *complq, int budget,
int *cleaned)
{
- struct idpf_splitq_tx_compl_desc *tx_desc;
+ struct idpf_splitq_4b_tx_compl_desc *tx_desc;
struct idpf_vport *vport = complq->vport;
s16 ntc = complq->next_to_clean;
- struct idpf_netdev_priv *np;
unsigned int complq_budget;
- bool complq_ok = true;
- int i;
+ bool flow, gen_flag;
+ u32 pos = ntc;
+
+ flow = test_bit(__IDPF_Q_FLOW_SCH_EN, complq->flags);
+ gen_flag = test_bit(__IDPF_Q_GEN_CHK, complq->flags);
complq_budget = vport->compln_clean_budget;
- tx_desc = &complq->comp[ntc];
+ tx_desc = flow ? &complq->comp[pos].common : &complq->comp_4b[pos];
ntc -= complq->desc_count;
do {
struct idpf_cleaned_stats cleaned_stats = { };
struct idpf_queue *tx_q;
- int rel_tx_qid;
u16 hw_head;
- u8 ctype; /* completion type */
- u16 gen;
-
- /* if the descriptor isn't done, no work yet to do */
- gen = (le16_to_cpu(tx_desc->qid_comptype_gen) &
- IDPF_TXD_COMPLQ_GEN_M) >> IDPF_TXD_COMPLQ_GEN_S;
- if (test_bit(__IDPF_Q_GEN_CHK, complq->flags) != gen)
- break;
-
- /* Find necessary info of TX queue to clean buffers */
- rel_tx_qid = (le16_to_cpu(tx_desc->qid_comptype_gen) &
- IDPF_TXD_COMPLQ_QID_M) >> IDPF_TXD_COMPLQ_QID_S;
- if (rel_tx_qid >= complq->txq_grp->num_txq ||
- !complq->txq_grp->txqs[rel_tx_qid]) {
- dev_err(&complq->vport->adapter->pdev->dev,
- "TxQ not found\n");
- goto fetch_next_desc;
- }
- tx_q = complq->txq_grp->txqs[rel_tx_qid];
+ int ctype;
- /* Determine completion type */
- ctype = (le16_to_cpu(tx_desc->qid_comptype_gen) &
- IDPF_TXD_COMPLQ_COMPL_TYPE_M) >>
- IDPF_TXD_COMPLQ_COMPL_TYPE_S;
+ ctype = idpf_parse_compl_desc(tx_desc, complq, &tx_q,
+ gen_flag);
switch (ctype) {
case IDPF_TXD_COMPLT_RE:
+ if (unlikely(!flow))
+ goto fetch_next_desc;
+
hw_head = le16_to_cpu(tx_desc->q_head_compl_tag.q_head);
idpf_tx_splitq_clean(tx_q, hw_head, budget,
&cleaned_stats, true);
break;
case IDPF_TXD_COMPLT_RS:
- idpf_tx_handle_rs_completion(tx_q, tx_desc,
- &cleaned_stats, budget);
+ if (flow)
+ idpf_tx_handle_rs_cmpl_fb(tx_q, tx_desc,
+ &cleaned_stats,
+ budget);
+ else
+ idpf_tx_handle_rs_cmpl_qb(tx_q, tx_desc,
+ &cleaned_stats,
+ budget);
break;
case IDPF_TXD_COMPLT_SW_MARKER:
idpf_tx_handle_sw_marker(tx_q);
break;
+ case -ENODATA:
+ goto exit_clean_complq;
+ case -EINVAL:
+ goto fetch_next_desc;
default:
dev_err(&tx_q->vport->adapter->pdev->dev,
"Unknown TX completion type: %d\n",
@@ -1836,59 +1902,24 @@ static bool idpf_tx_clean_complq(struct idpf_queue *complq, int budget,
u64_stats_update_end(&tx_q->stats_sync);
fetch_next_desc:
- tx_desc++;
+ pos++;
ntc++;
if (unlikely(!ntc)) {
ntc -= complq->desc_count;
- tx_desc = &complq->comp[0];
- change_bit(__IDPF_Q_GEN_CHK, complq->flags);
+ pos = 0;
+ gen_flag = !gen_flag;
}
+ tx_desc = flow ? &complq->comp[pos].common :
+ &complq->comp_4b[pos];
prefetch(tx_desc);
/* update budget accounting */
complq_budget--;
} while (likely(complq_budget));
- /* Store the state of the complq to be used later in deciding if a
- * TXQ can be started again
- */
- if (unlikely(IDPF_TX_COMPLQ_PENDING(complq->txq_grp) >
- IDPF_TX_COMPLQ_OVERFLOW_THRESH(complq)))
- complq_ok = false;
-
- np = netdev_priv(complq->vport->netdev);
- for (i = 0; i < complq->txq_grp->num_txq; ++i) {
- struct idpf_queue *tx_q = complq->txq_grp->txqs[i];
- struct netdev_queue *nq;
- bool dont_wake;
-
- /* We didn't clean anything on this queue, move along */
- if (!tx_q->cleaned_bytes)
- continue;
-
- *cleaned += tx_q->cleaned_pkts;
-
- /* Update BQL */
- nq = netdev_get_tx_queue(tx_q->vport->netdev, tx_q->idx);
-
- dont_wake = !complq_ok || IDPF_TX_BUF_RSV_LOW(tx_q) ||
- np->state != __IDPF_VPORT_UP ||
- !netif_carrier_ok(tx_q->vport->netdev);
- /* Check if the TXQ needs to and can be restarted */
- __netif_txq_completed_wake(nq, tx_q->cleaned_pkts, tx_q->cleaned_bytes,
- IDPF_DESC_UNUSED(tx_q), IDPF_TX_WAKE_THRESH,
- dont_wake);
-
- /* Reset cleaned stats for the next time this queue is
- * cleaned
- */
- tx_q->cleaned_bytes = 0;
- tx_q->cleaned_pkts = 0;
- }
-
- ntc += complq->desc_count;
- complq->next_to_clean = ntc;
+exit_clean_complq:
+ idpf_tx_finalize_complq(complq, ntc, gen_flag, cleaned);
return !!complq_budget;
}
diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.h b/drivers/net/ethernet/intel/idpf/idpf_txrx.h
index 2584bd94363f..3e15ed779860 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.h
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.h
@@ -577,6 +577,7 @@ struct idpf_queue {
struct idpf_flex_tx_ctx_desc *flex_ctx;
struct idpf_splitq_tx_compl_desc *comp;
+ struct idpf_splitq_4b_tx_compl_desc *comp_4b;
void *desc_ring;
};
@@ -821,6 +822,49 @@ static inline void idpf_tx_splitq_build_desc(union idpf_tx_flex_desc *desc,
idpf_tx_splitq_build_flow_desc(desc, params, td_cmd, size);
}
+/**
+ * idpf_parse_compl_desc - Parse the completion descriptor
+ * @desc: completion descriptor to be parsed
+ * @complq: completion queue containing the descriptor
+ * @txq: returns corresponding Tx queue for a given descriptor
+ * @gen_flag: current generation flag in the completion queue
+ *
+ * Returns completion type from descriptor or negative value in case of error:
+ * -ENODATA if there is no completion descriptor to be cleaned
+ * -EINVAL if no Tx queue has been found for the completion queue
+ */
+static inline int
+idpf_parse_compl_desc(struct idpf_splitq_4b_tx_compl_desc *desc,
+ struct idpf_queue *complq, struct idpf_queue **txq,
+ bool gen_flag)
+{
+ int rel_tx_qid;
+ u8 ctype; /* completion type */
+ u16 gen;
+
+ /* if the descriptor isn't done, no work yet to do */
+ gen = (le16_to_cpu(desc->qid_comptype_gen) &
+ IDPF_TXD_COMPLQ_GEN_M) >> IDPF_TXD_COMPLQ_GEN_S;
+ if (gen_flag != gen)
+ return -ENODATA;
+
+ /* Find necessary info of TX queue to clean buffers */
+ rel_tx_qid = (le16_to_cpu(desc->qid_comptype_gen) &
+ IDPF_TXD_COMPLQ_QID_M) >> IDPF_TXD_COMPLQ_QID_S;
+ if (rel_tx_qid >= complq->txq_grp->num_txq ||
+ !complq->txq_grp->txqs[rel_tx_qid])
+ return -EINVAL;
+
+ *txq = complq->txq_grp->txqs[rel_tx_qid];
+
+ /* Determine completion type */
+ ctype = (le16_to_cpu(desc->qid_comptype_gen) &
+ IDPF_TXD_COMPLQ_COMPL_TYPE_M) >>
+ IDPF_TXD_COMPLQ_COMPL_TYPE_S;
+
+ return ctype;
+}
+
/**
* idpf_vport_intr_set_wb_on_itr - enable descriptor writeback on disabled interrupts
* @q_vector: pointer to queue vector struct
--
2.43.0
next prev parent reply other threads:[~2023-12-23 2:59 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-12-23 2:55 [PATCH RFC net-next 00/34] Christmas 3-serie XDP for idpf (+generic stuff) Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 01/34] idpf: reuse libie's definitions of parsed ptype structures Alexander Lobakin
2023-12-27 15:43 ` Willem de Bruijn
2024-01-08 16:04 ` Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 02/34] idpf: pack &idpf_queue way more efficiently Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 03/34] idpf: remove legacy Page Pool Ethtool stats Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 04/34] libie: support different types of buffers for Rx Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 05/34] idpf: convert header split mode to libie + napi_build_skb() Alexander Lobakin
2023-12-27 15:30 ` Willem de Bruijn
2024-01-08 16:17 ` Alexander Lobakin
2024-01-09 13:59 ` Willem de Bruijn
2024-01-11 13:09 ` Alexander Lobakin
2024-01-09 14:43 ` Eric Dumazet
2023-12-23 2:55 ` [PATCH RFC net-next 06/34] idpf: use libie Rx buffer management for payload buffer Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 07/34] libie: add Tx buffer completion helpers Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 08/34] idpf: convert to libie Tx buffer completion Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 09/34] bpf, xdp: constify some bpf_prog * function arguments Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 10/34] xdp: constify read-only arguments of some static inline helpers Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 11/34] xdp: allow attaching already registered memory model to xdp_rxq_info Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 12/34] xdp: add generic xdp_buff_add_frag() Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 13/34] xdp: add generic xdp_build_skb_from_buff() Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 14/34] xdp: get rid of xdp_frame::mem.id Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 15/34] page_pool: add inline helper to sync VA for device (for XDP_TX) Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 16/34] jump_label: export static_key_slow_{inc,dec}_cpuslocked() Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 17/34] libie: support native XDP and register memory model Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 18/34] libie: add a couple of XDP helpers Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 19/34] idpf: stop using macros for accessing queue descriptors Alexander Lobakin
2023-12-23 2:55 ` Alexander Lobakin [this message]
2023-12-23 2:55 ` [PATCH RFC net-next 21/34] idpf: prepare structures to support xdp Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 22/34] idpf: implement XDP_SETUP_PROG in ndo_bpf for splitq Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 23/34] idpf: use generic functions to build xdp_buff and skb Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 24/34] idpf: add support for XDP on Rx Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 25/34] idpf: add support for .ndo_xdp_xmit() Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 26/34] xdp: add generic XSk xdp_buff -> skb conversion Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 27/34] idpf: add support for sw interrupt Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 28/34] idpf: add relative queue id member to idpf_queue Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 29/34] idpf: add vc functions to manage selected queues Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 30/34] idpf: move search rx and tx queues to header Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 31/34] idpf: add XSk pool initialization Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 32/34] idpf: implement Tx path for AF_XDP Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 33/34] idpf: implement Rx " Alexander Lobakin
2023-12-23 2:55 ` [PATCH RFC net-next 34/34] idpf: enable XSk features and ndo_xsk_wakeup Alexander Lobakin
2023-12-26 20:23 ` [PATCH RFC net-next 00/34] Christmas 3-serie XDP for idpf (+generic stuff) Willem de Bruijn
2024-01-08 16:01 ` Alexander Lobakin
2024-01-08 16:09 ` Willem de Bruijn
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