diff mbox series

[net-next,V3] eth: fbnic: Add ethtool support for IRQ coalescing

Message ID 20250215035325.752824-1-mohsin.bashr@gmail.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series [net-next,V3] eth: fbnic: Add ethtool support for IRQ coalescing | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
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 9 of 9 maintainers
netdev/build_clang success Errors and warnings before: 1 this patch: 1
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 81 exceeds 80 columns WARNING: line length of 87 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2025-02-15--18-00 (tests: 891)

Commit Message

Mohsin Bashir Feb. 15, 2025, 3:53 a.m. UTC
Add ethtool support to configure the IRQ coalescing behavior. Support
separate timers for Rx and Tx for time based coalescing. For frame based
configuration, currently we only support the Rx side.

The hardware allows configuration of descriptor count instead of frame
count requiring conversion between the two. We assume 2 descriptors
per frame, one for the metadata and one for the data segment.

When rx-frames are not configured, we set the RX descriptor count to
half the ring size as a fail safe.

Default configuration:
ethtool -c eth0 | grep -E "rx-usecs:|tx-usecs:|rx-frames:"
rx-usecs:       30
rx-frames:      0
tx-usecs:       35

IRQ rate test:
With single iperf flow we monitor IRQ rate while changing the tx-usesc and
rx-usecs to high and low values.

ethtool -C eth0 rx-frames 8192 rx-usecs 150 tx-usecs 150
irq/sec   13k
irq/sec   14k
irq/sec   14k

ethtool -C eth0 rx-frames 8192 rx-usecs 10 tx-usecs 10
irq/sec  27k
irq/sec  28k
irq/sec  28k

Validating the use of extack:
ethtool -C eth0 rx-frames 16384
netlink error: fbnic: rx_frames is above device max
netlink error: Invalid argument

Signed-off-by: Mohsin Bashir <mohsin.bashr@gmail.com>
---
V3:
- Rebased on the net-next

V2: https://lore.kernel.org/netdev/20250214035037.650291-1-mohsin.bashr@gmail.com
- Update fbnic_set_coalesce() to use extack to highlight incorrect config
- Simplify fbnic_config_rx_frames()

V1: https://lore.kernel.org/netdev/20250212234946.2536116-1-mohsin.bashr@gmail.com
---
 drivers/net/ethernet/meta/fbnic/fbnic.h       |  3 +
 .../net/ethernet/meta/fbnic/fbnic_ethtool.c   | 60 +++++++++++++++++++
 .../net/ethernet/meta/fbnic/fbnic_netdev.c    |  4 ++
 .../net/ethernet/meta/fbnic/fbnic_netdev.h    |  6 ++
 drivers/net/ethernet/meta/fbnic/fbnic_txrx.c  | 53 +++++++++++++---
 drivers/net/ethernet/meta/fbnic/fbnic_txrx.h  |  3 +
 6 files changed, 121 insertions(+), 8 deletions(-)

Comments

Andrew Lunn Feb. 15, 2025, 7 p.m. UTC | #1
> 
> Signed-off-by: Mohsin Bashir <mohsin.bashr@gmail.com>
> ---
> V3:
> - Rebased on the net-next
> 
> V2: https://lore.kernel.org/netdev/20250214035037.650291-1-mohsin.bashr@gmail.com
> - Update fbnic_set_coalesce() to use extack to highlight incorrect config
> - Simplify fbnic_config_rx_frames()

When posting a new version you should add any Reviewed-by: and
Acked-by tags you received. Maybe consider using b4, it will collect
and add them for you.

	Andrew
diff mbox series

Patch

diff --git a/drivers/net/ethernet/meta/fbnic/fbnic.h b/drivers/net/ethernet/meta/fbnic/fbnic.h
index 37f81db1fc30..4ca7b99ef131 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic.h
@@ -186,6 +186,9 @@  void fbnic_dbg_exit(void);
 void fbnic_csr_get_regs(struct fbnic_dev *fbd, u32 *data, u32 *regs_version);
 int fbnic_csr_regs_len(struct fbnic_dev *fbd);
 
+void fbnic_config_txrx_usecs(struct fbnic_napi_vector *nv, u32 arm);
+void fbnic_config_rx_frames(struct fbnic_napi_vector *nv);
+
 enum fbnic_boards {
 	fbnic_board_asic
 };
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c b/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c
index fb7139a1da46..c1477aad98a0 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_ethtool.c
@@ -136,6 +136,61 @@  static void fbnic_clone_free(struct fbnic_net *clone)
 	kfree(clone);
 }
 
+static int fbnic_get_coalesce(struct net_device *netdev,
+			      struct ethtool_coalesce *ec,
+			      struct kernel_ethtool_coalesce *kernel_coal,
+			      struct netlink_ext_ack *extack)
+{
+	struct fbnic_net *fbn = netdev_priv(netdev);
+
+	ec->tx_coalesce_usecs = fbn->tx_usecs;
+	ec->rx_coalesce_usecs = fbn->rx_usecs;
+	ec->rx_max_coalesced_frames = fbn->rx_max_frames;
+
+	return 0;
+}
+
+static int fbnic_set_coalesce(struct net_device *netdev,
+			      struct ethtool_coalesce *ec,
+			      struct kernel_ethtool_coalesce *kernel_coal,
+			      struct netlink_ext_ack *extack)
+{
+	struct fbnic_net *fbn = netdev_priv(netdev);
+
+	/* Verify against hardware limits */
+	if (ec->rx_coalesce_usecs > FIELD_MAX(FBNIC_INTR_CQ_REARM_RCQ_TIMEOUT)) {
+		NL_SET_ERR_MSG_MOD(extack, "rx_usecs is above device max");
+		return -EINVAL;
+	}
+	if (ec->tx_coalesce_usecs > FIELD_MAX(FBNIC_INTR_CQ_REARM_TCQ_TIMEOUT)) {
+		NL_SET_ERR_MSG_MOD(extack, "tx_usecs is above device max");
+		return -EINVAL;
+	}
+	if (ec->rx_max_coalesced_frames >
+	    FIELD_MAX(FBNIC_QUEUE_RIM_THRESHOLD_RCD_MASK) /
+	    FBNIC_MIN_RXD_PER_FRAME) {
+		NL_SET_ERR_MSG_MOD(extack, "rx_frames is above device max");
+		return -EINVAL;
+	}
+
+	fbn->tx_usecs = ec->tx_coalesce_usecs;
+	fbn->rx_usecs = ec->rx_coalesce_usecs;
+	fbn->rx_max_frames = ec->rx_max_coalesced_frames;
+
+	if (netif_running(netdev)) {
+		int i;
+
+		for (i = 0; i < fbn->num_napi; i++) {
+			struct fbnic_napi_vector *nv = fbn->napi[i];
+
+			fbnic_config_txrx_usecs(nv, 0);
+			fbnic_config_rx_frames(nv);
+		}
+	}
+
+	return 0;
+}
+
 static void fbnic_get_strings(struct net_device *dev, u32 sset, u8 *data)
 {
 	int i;
@@ -1287,10 +1342,15 @@  fbnic_get_eth_mac_stats(struct net_device *netdev,
 }
 
 static const struct ethtool_ops fbnic_ethtool_ops = {
+	.supported_coalesce_params	=
+				  ETHTOOL_COALESCE_USECS |
+				  ETHTOOL_COALESCE_RX_MAX_FRAMES,
 	.rxfh_max_num_contexts	= FBNIC_RPC_RSS_TBL_COUNT,
 	.get_drvinfo		= fbnic_get_drvinfo,
 	.get_regs_len		= fbnic_get_regs_len,
 	.get_regs		= fbnic_get_regs,
+	.get_coalesce		= fbnic_get_coalesce,
+	.set_coalesce		= fbnic_set_coalesce,
 	.get_strings		= fbnic_get_strings,
 	.get_ethtool_stats	= fbnic_get_ethtool_stats,
 	.get_sset_count		= fbnic_get_sset_count,
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c
index b12672d1607e..34300241f7e1 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.c
@@ -638,6 +638,10 @@  struct net_device *fbnic_netdev_alloc(struct fbnic_dev *fbd)
 	fbn->ppq_size = FBNIC_PPQ_SIZE_DEFAULT;
 	fbn->rcq_size = FBNIC_RCQ_SIZE_DEFAULT;
 
+	fbn->tx_usecs = FBNIC_TX_USECS_DEFAULT;
+	fbn->rx_usecs = FBNIC_RX_USECS_DEFAULT;
+	fbn->rx_max_frames = FBNIC_RX_FRAMES_DEFAULT;
+
 	default_queues = netif_get_num_default_rss_queues();
 	if (default_queues > fbd->max_num_queues)
 		default_queues = fbd->max_num_queues;
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.h b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.h
index a392ac1cc4f2..46af92a8f781 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_netdev.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_netdev.h
@@ -12,6 +12,7 @@ 
 #include "fbnic_txrx.h"
 
 #define FBNIC_MAX_NAPI_VECTORS		128u
+#define FBNIC_MIN_RXD_PER_FRAME		2
 
 struct fbnic_net {
 	struct fbnic_ring *tx[FBNIC_MAX_TXQS];
@@ -27,6 +28,11 @@  struct fbnic_net {
 	u32 ppq_size;
 	u32 rcq_size;
 
+	u16 rx_usecs;
+	u16 tx_usecs;
+
+	u32 rx_max_frames;
+
 	u16 num_napi;
 
 	struct phylink *phylink;
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
index 24d2b528b66c..8c4d494b0637 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
@@ -2054,9 +2054,51 @@  static void fbnic_config_drop_mode_rcq(struct fbnic_napi_vector *nv,
 	fbnic_ring_wr32(rcq, FBNIC_QUEUE_RDE_CTL0, rcq_ctl);
 }
 
+static void fbnic_config_rim_threshold(struct fbnic_ring *rcq, u16 nv_idx, u32 rx_desc)
+{
+	u32 threshold;
+
+	/* Set the threhsold to half the ring size if rx_frames
+	 * is not configured
+	 */
+	threshold = rx_desc ? : rcq->size_mask / 2;
+
+	fbnic_ring_wr32(rcq, FBNIC_QUEUE_RIM_CTL, nv_idx);
+	fbnic_ring_wr32(rcq, FBNIC_QUEUE_RIM_THRESHOLD, threshold);
+}
+
+void fbnic_config_txrx_usecs(struct fbnic_napi_vector *nv, u32 arm)
+{
+	struct fbnic_net *fbn = netdev_priv(nv->napi.dev);
+	struct fbnic_dev *fbd = nv->fbd;
+	u32 val = arm;
+
+	val |= FIELD_PREP(FBNIC_INTR_CQ_REARM_RCQ_TIMEOUT, fbn->rx_usecs) |
+	       FBNIC_INTR_CQ_REARM_RCQ_TIMEOUT_UPD_EN;
+	val |= FIELD_PREP(FBNIC_INTR_CQ_REARM_TCQ_TIMEOUT, fbn->tx_usecs) |
+	       FBNIC_INTR_CQ_REARM_TCQ_TIMEOUT_UPD_EN;
+
+	fbnic_wr32(fbd, FBNIC_INTR_CQ_REARM(nv->v_idx), val);
+}
+
+void fbnic_config_rx_frames(struct fbnic_napi_vector *nv)
+{
+	struct fbnic_net *fbn = netdev_priv(nv->napi.dev);
+	int i;
+
+	for (i = nv->txt_count; i < nv->rxt_count + nv->txt_count; i++) {
+		struct fbnic_q_triad *qt = &nv->qt[i];
+
+		fbnic_config_rim_threshold(&qt->cmpl, nv->v_idx,
+					   fbn->rx_max_frames *
+					   FBNIC_MIN_RXD_PER_FRAME);
+	}
+}
+
 static void fbnic_enable_rcq(struct fbnic_napi_vector *nv,
 			     struct fbnic_ring *rcq)
 {
+	struct fbnic_net *fbn = netdev_priv(nv->napi.dev);
 	u32 log_size = fls(rcq->size_mask);
 	u32 rcq_ctl;
 
@@ -2084,8 +2126,8 @@  static void fbnic_enable_rcq(struct fbnic_napi_vector *nv,
 	fbnic_ring_wr32(rcq, FBNIC_QUEUE_RCQ_SIZE, log_size & 0xf);
 
 	/* Store interrupt information for the completion queue */
-	fbnic_ring_wr32(rcq, FBNIC_QUEUE_RIM_CTL, nv->v_idx);
-	fbnic_ring_wr32(rcq, FBNIC_QUEUE_RIM_THRESHOLD, rcq->size_mask / 2);
+	fbnic_config_rim_threshold(rcq, nv->v_idx, fbn->rx_max_frames *
+						   FBNIC_MIN_RXD_PER_FRAME);
 	fbnic_ring_wr32(rcq, FBNIC_QUEUE_RIM_MASK, 0);
 
 	/* Enable queue */
@@ -2124,12 +2166,7 @@  void fbnic_enable(struct fbnic_net *fbn)
 
 static void fbnic_nv_irq_enable(struct fbnic_napi_vector *nv)
 {
-	struct fbnic_dev *fbd = nv->fbd;
-	u32 val;
-
-	val = FBNIC_INTR_CQ_REARM_INTR_UNMASK;
-
-	fbnic_wr32(fbd, FBNIC_INTR_CQ_REARM(nv->v_idx), val);
+	fbnic_config_txrx_usecs(nv, FBNIC_INTR_CQ_REARM_INTR_UNMASK);
 }
 
 void fbnic_napi_enable(struct fbnic_net *fbn)
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h
index b53a7d28ecd3..1ed78b744635 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_txrx.h
@@ -31,6 +31,9 @@  struct fbnic_net;
 #define FBNIC_HPQ_SIZE_DEFAULT		256
 #define FBNIC_PPQ_SIZE_DEFAULT		256
 #define FBNIC_RCQ_SIZE_DEFAULT		1024
+#define FBNIC_TX_USECS_DEFAULT		35
+#define FBNIC_RX_USECS_DEFAULT		30
+#define FBNIC_RX_FRAMES_DEFAULT		0
 
 #define FBNIC_RX_TROOM \
 	SKB_DATA_ALIGN(sizeof(struct skb_shared_info))