diff mbox series

[net-next,v3,09/10] bnxt_en: Extend queue stop/start for TX rings

Message ID 20250204004609.1107078-10-michael.chan@broadcom.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series bnxt_en: Add NPAR 1.2 and TPH support | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 2 this patch: 2
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch warning WARNING: line length of 82 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 2 this patch: 2
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2025-02-04--15-00 (tests: 886)

Commit Message

Michael Chan Feb. 4, 2025, 12:46 a.m. UTC 
From: Somnath Kotur <somnath.kotur@broadcom.com>

In order to use queue_stop/queue_start to support the new Steering
Tags, we need to free the TX ring and TX completion ring if it is a
combined channel with TX/RX sharing the same NAPI.  Otherwise
TX completions will not have the updated Steering Tag.  If TPH is
not enabled, we just stop the TX ring without freeing the TX/TX cmpl
rings.  With that we can now add napi_disable() and napi_enable()
during queue_stop()/ queue_start().  This will guarantee that NAPI
will stop processing the completion entries in case there are
additional pending entries in the completion rings after queue_stop().

There could be some NQEs sitting unprocessed while NAPI is disabled
thereby leaving the NQ unarmed.  Explicitly re-arm the NQ after
napi_enable() in queue start so that NAPI will resume properly.

Error handling in bnxt_queue_start() requires a reset.  If a TX
ring cannot be allocated or initialized properly, it will cause
TX timeout.  The reset will also free any partially allocated
rings.

Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
---
Cc: David Wei <dw@davidwei.uk>

v3:
Fix build bot warning.
Only free TX/TX cmpl rings when TPH is enabled.

v2:
Add reset for error handling in queue_start().
Fix compile error.

Discussion about adding napi_disable()/napi_enable():

https://lore.kernel.org/netdev/5336d624-8d8b-40a6-b732-b020e4a119a2@davidwei.uk/#t
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 132 ++++++++++++++++++++--
 1 file changed, 122 insertions(+), 10 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 019a8433b0d6..fee9baff9e5a 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -7368,6 +7368,22 @@  static int hwrm_ring_free_send_msg(struct bnxt *bp,
 	return 0;
 }
 
+static void bnxt_hwrm_tx_ring_free(struct bnxt *bp, struct bnxt_tx_ring_info *txr,
+				   bool close_path)
+{
+	struct bnxt_ring_struct *ring = &txr->tx_ring_struct;
+	u32 cmpl_ring_id;
+
+	if (ring->fw_ring_id == INVALID_HW_RING_ID)
+		return;
+
+	cmpl_ring_id = close_path ? bnxt_cp_ring_for_tx(bp, txr) :
+		       INVALID_HW_RING_ID;
+	hwrm_ring_free_send_msg(bp, ring, RING_FREE_REQ_RING_TYPE_TX,
+				cmpl_ring_id);
+	ring->fw_ring_id = INVALID_HW_RING_ID;
+}
+
 static void bnxt_hwrm_rx_ring_free(struct bnxt *bp,
 				   struct bnxt_rx_ring_info *rxr,
 				   bool close_path)
@@ -11274,6 +11290,75 @@  int bnxt_reserve_rings(struct bnxt *bp, bool irq_re_init)
 	return 0;
 }
 
+static void bnxt_tx_queue_stop(struct bnxt *bp, int idx)
+{
+	struct bnxt_tx_ring_info *txr;
+	struct netdev_queue *txq;
+	struct bnxt_napi *bnapi;
+	int i;
+
+	bnapi = bp->bnapi[idx];
+	bnxt_for_each_napi_tx(i, bnapi, txr) {
+		WRITE_ONCE(txr->dev_state, BNXT_DEV_STATE_CLOSING);
+		synchronize_net();
+
+		if (!(bnapi->flags & BNXT_NAPI_FLAG_XDP)) {
+			txq = netdev_get_tx_queue(bp->dev, txr->txq_index);
+			if (txq) {
+				__netif_tx_lock_bh(txq);
+				netif_tx_stop_queue(txq);
+				__netif_tx_unlock_bh(txq);
+			}
+		}
+
+		if (!bp->tph_mode)
+			continue;
+
+		bnxt_hwrm_tx_ring_free(bp, txr, true);
+		bnxt_hwrm_cp_ring_free(bp, txr->tx_cpr);
+		bnxt_free_one_tx_ring_skbs(bp, txr, txr->txq_index);
+		bnxt_clear_one_cp_ring(bp, txr->tx_cpr);
+	}
+}
+
+static int bnxt_tx_queue_start(struct bnxt *bp, int idx)
+{
+	struct bnxt_tx_ring_info *txr;
+	struct netdev_queue *txq;
+	struct bnxt_napi *bnapi;
+	int rc, i;
+
+	bnapi = bp->bnapi[idx];
+	bnxt_for_each_napi_tx(i, bnapi, txr) {
+		if (!bp->tph_mode)
+			goto start_tx;
+
+		rc = bnxt_hwrm_cp_ring_alloc_p5(bp, txr->tx_cpr);
+		if (rc)
+			return rc;
+
+		rc = bnxt_hwrm_tx_ring_alloc(bp, txr, false);
+		if (rc)
+			return rc;
+
+		txr->tx_prod = 0;
+		txr->tx_cons = 0;
+		txr->tx_hw_cons = 0;
+start_tx:
+		WRITE_ONCE(txr->dev_state, 0);
+		synchronize_net();
+
+		if (bnapi->flags & BNXT_NAPI_FLAG_XDP)
+			continue;
+
+		txq = netdev_get_tx_queue(bp->dev, txr->txq_index);
+		if (txq)
+			netif_tx_start_queue(txq);
+	}
+
+	return 0;
+}
+
 static void bnxt_free_irq(struct bnxt *bp)
 {
 	struct bnxt_irq *irq;
@@ -15638,6 +15723,7 @@  static int bnxt_queue_start(struct net_device *dev, void *qmem, int idx)
 	struct bnxt_rx_ring_info *rxr, *clone;
 	struct bnxt_cp_ring_info *cpr;
 	struct bnxt_vnic_info *vnic;
+	struct bnxt_napi *bnapi;
 	int i, rc;
 
 	rxr = &bp->rx_ring[idx];
@@ -15655,27 +15741,42 @@  static int bnxt_queue_start(struct net_device *dev, void *qmem, int idx)
 
 	bnxt_copy_rx_ring(bp, rxr, clone);
 
+	bnapi = rxr->bnapi;
+	cpr = &bnapi->cp_ring;
 	rc = bnxt_hwrm_rx_ring_alloc(bp, rxr);
 	if (rc)
-		return rc;
+		goto err_reset_rx;
 
 	if (bp->tph_mode) {
 		rc = bnxt_hwrm_cp_ring_alloc_p5(bp, rxr->rx_cpr);
 		if (rc)
-			goto err_free_hwrm_rx_ring;
+			goto err_reset_rx;
 	}
 
 	rc = bnxt_hwrm_rx_agg_ring_alloc(bp, rxr);
 	if (rc)
-		goto err_free_hwrm_cp_ring;
+		goto err_reset_rx;
 
 	bnxt_db_write(bp, &rxr->rx_db, rxr->rx_prod);
 	if (bp->flags & BNXT_FLAG_AGG_RINGS)
 		bnxt_db_write(bp, &rxr->rx_agg_db, rxr->rx_agg_prod);
 
-	cpr = &rxr->bnapi->cp_ring;
 	cpr->sw_stats->rx.rx_resets++;
 
+	if (bp->flags & BNXT_FLAG_SHARED_RINGS) {
+		cpr->sw_stats->tx.tx_resets++;
+		rc = bnxt_tx_queue_start(bp, idx);
+		if (rc) {
+			netdev_warn(bp->dev,
+				    "tx queue restart failed: rc=%d\n", rc);
+			bnapi->tx_fault = 1;
+			goto err_reset;
+		}
+	}
+
+	napi_enable(&bnapi->napi);
+	bnxt_db_nq_arm(bp, &cpr->cp_db, cpr->cp_raw_cons);
+
 	for (i = 0; i <= BNXT_VNIC_NTUPLE; i++) {
 		vnic = &bp->vnic_info[i];
 
@@ -15692,11 +15793,12 @@  static int bnxt_queue_start(struct net_device *dev, void *qmem, int idx)
 
 	return 0;
 
-err_free_hwrm_cp_ring:
-	if (bp->tph_mode)
-		bnxt_hwrm_cp_ring_free(bp, rxr->rx_cpr);
-err_free_hwrm_rx_ring:
-	bnxt_hwrm_rx_ring_free(bp, rxr, false);
+err_reset_rx:
+	rxr->bnapi->in_reset = true;
+err_reset:
+	napi_enable(&bnapi->napi);
+	bnxt_db_nq_arm(bp, &cpr->cp_db, cpr->cp_raw_cons);
+	bnxt_reset_task(bp, true);
 	return rc;
 }
 
@@ -15704,7 +15806,9 @@  static int bnxt_queue_stop(struct net_device *dev, void *qmem, int idx)
 {
 	struct bnxt *bp = netdev_priv(dev);
 	struct bnxt_rx_ring_info *rxr;
+	struct bnxt_cp_ring_info *cpr;
 	struct bnxt_vnic_info *vnic;
+	struct bnxt_napi *bnapi;
 	int i;
 
 	for (i = 0; i <= BNXT_VNIC_NTUPLE; i++) {
@@ -15716,17 +15820,25 @@  static int bnxt_queue_stop(struct net_device *dev, void *qmem, int idx)
 	/* Make sure NAPI sees that the VNIC is disabled */
 	synchronize_net();
 	rxr = &bp->rx_ring[idx];
-	cancel_work_sync(&rxr->bnapi->cp_ring.dim.work);
+	bnapi = rxr->bnapi;
+	cpr = &bnapi->cp_ring;
+	cancel_work_sync(&cpr->dim.work);
 	bnxt_hwrm_rx_ring_free(bp, rxr, false);
 	bnxt_hwrm_rx_agg_ring_free(bp, rxr, false);
 	page_pool_disable_direct_recycling(rxr->page_pool);
 	if (bnxt_separate_head_pool())
 		page_pool_disable_direct_recycling(rxr->head_pool);
 
+	if (bp->flags & BNXT_FLAG_SHARED_RINGS)
+		bnxt_tx_queue_stop(bp, idx);
+
+	napi_disable(&bnapi->napi);
+
 	if (bp->tph_mode) {
 		bnxt_hwrm_cp_ring_free(bp, rxr->rx_cpr);
 		bnxt_clear_one_cp_ring(bp, rxr->rx_cpr);
 	}
+	bnxt_db_nq(bp, &cpr->cp_db, cpr->cp_raw_cons);
 
 	memcpy(qmem, rxr, sizeof(*rxr));
 	bnxt_init_rx_ring_struct(bp, qmem);