Merge tag 'blk-dim-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux

Saeed Mamameed says:

====================
Generic DIM

From: Tal Gilboa and Yamin Fridman

Implement net DIM over a generic DIM library, add RDMA DIM

dim.h lib exposes an implementation of the DIM algorithm for
dynamically-tuned interrupt moderation for networking interfaces.

We want a similar functionality for other protocols, which might need to
optimize interrupts differently. Main motivation here is DIM for NVMf
storage protocol.

Current DIM implementation prioritizes reducing interrupt overhead over
latency. Also, in order to reduce DIM's own overhead, the algorithm might
take some time to identify it needs to change profiles. While this is
acceptable for networking, it might not work well on other scenarios.

Here we propose a new structure to DIM. The idea is to allow a slightly
modified functionality without the risk of breaking Net DIM behavior for
netdev. We verified there are no degradations in current DIM behavior with
the modified solution.

Suggested solution:
- Common logic is implemented in lib/dim/dim.c
- Net DIM (existing) logic is implemented in lib/dim/net_dim.c, which uses
  the common logic in dim.c
- Any new DIM logic will be implemented in "lib/dim/new_dim.c".
  This new implementation will expose modified versions of profiles,
  dim_step() and dim_decision().
- DIM API is declared in include/linux/dim.h for all implementations.

Pros for this solution are:
- Zero impact on existing net_dim implementation and usage
- Relatively more code reuse (compared to two separate solutions)
- Increased extensibility
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 30 insertions, 31 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
index 2391e3cfb56b..7845aa5bf6be 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
@@ -34,6 +34,7 @@ config MLX5_CORE_EN
 	depends on NETDEVICES && ETHERNET && INET && PCI && MLX5_CORE
 	depends on IPV6=y || IPV6=n || MLX5_CORE=m
 	select PAGE_POOL
+	select DIMLIB
 	default n
 	---help---
 	  Ethernet support in Mellanox Technologies ConnectX-4 NIC.
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index 992d5cb646b2..3fe3fe128256 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -48,7 +48,7 @@
 #include <linux/rhashtable.h>
 #include <net/switchdev.h>
 #include <net/xdp.h>
-#include <linux/net_dim.h>
+#include <linux/dim.h>
 #include <linux/bits.h>
 #include "wq.h"
 #include "mlx5_core.h"
@@ -238,9 +238,9 @@ struct mlx5e_params {
 	u16 num_channels;
 	u8  num_tc;
 	bool rx_cqe_compress_def;
-	struct net_dim_cq_moder rx_cq_moderation;
-	struct net_dim_cq_moder tx_cq_moderation;
 	bool tunneled_offload_en;
+	struct dim_cq_moder rx_cq_moderation;
+	struct dim_cq_moder tx_cq_moderation;
 	bool lro_en;
 	u8  tx_min_inline_mode;
 	bool vlan_strip_disable;
@@ -356,7 +356,7 @@ struct mlx5e_txqsq {
 	/* dirtied @completion */
 	u16                        cc;
 	u32                        dma_fifo_cc;
-	struct net_dim             dim; /* Adaptive Moderation */
+	struct dim                 dim; /* Adaptive Moderation */
 
 	/* dirtied @xmit */
 	u16                        pc ____cacheline_aligned_in_smp;
@@ -596,7 +596,7 @@ struct mlx5e_rq {
 	int                    ix;
 	unsigned int           hw_mtu;
 
-	struct net_dim         dim; /* Dynamic Interrupt Moderation */
+	struct dim         dim; /* Dynamic Interrupt Moderation */
 
 	/* XDP */
 	struct bpf_prog       *xdp_prog;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_dim.c b/drivers/net/ethernet/mellanox/mlx5/core/en_dim.c
index d67adf70a97b..ca9cfbf57d8f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_dim.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_dim.c
@@ -30,22 +30,22 @@
  * SOFTWARE.
  */
 
-#include <linux/net_dim.h>
+#include <linux/dim.h>
 #include "en.h"
 
 static void
-mlx5e_complete_dim_work(struct net_dim *dim, struct net_dim_cq_moder moder,
+mlx5e_complete_dim_work(struct dim *dim, struct dim_cq_moder moder,
 			struct mlx5_core_dev *mdev, struct mlx5_core_cq *mcq)
 {
 	mlx5_core_modify_cq_moderation(mdev, mcq, moder.usec, moder.pkts);
-	dim->state = NET_DIM_START_MEASURE;
+	dim->state = DIM_START_MEASURE;
 }
 
 void mlx5e_rx_dim_work(struct work_struct *work)
 {
-	struct net_dim *dim = container_of(work, struct net_dim, work);
+	struct dim *dim = container_of(work, struct dim, work);
 	struct mlx5e_rq *rq = container_of(dim, struct mlx5e_rq, dim);
-	struct net_dim_cq_moder cur_moder =
+	struct dim_cq_moder cur_moder =
 		net_dim_get_rx_moderation(dim->mode, dim->profile_ix);
 
 	mlx5e_complete_dim_work(dim, cur_moder, rq->mdev, &rq->cq.mcq);
@@ -53,9 +53,9 @@ void mlx5e_rx_dim_work(struct work_struct *work)
 
 void mlx5e_tx_dim_work(struct work_struct *work)
 {
-	struct net_dim *dim = container_of(work, struct net_dim, work);
+	struct dim *dim = container_of(work, struct dim, work);
 	struct mlx5e_txqsq *sq = container_of(dim, struct mlx5e_txqsq, dim);
-	struct net_dim_cq_moder cur_moder =
+	struct dim_cq_moder cur_moder =
 		net_dim_get_tx_moderation(dim->mode, dim->profile_ix);
 
 	mlx5e_complete_dim_work(dim, cur_moder, sq->cq.mdev, &sq->cq.mcq);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index ea59097dd4f8..05f07331ab41 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -466,7 +466,7 @@ static int mlx5e_set_channels(struct net_device *dev,
 int mlx5e_ethtool_get_coalesce(struct mlx5e_priv *priv,
 			       struct ethtool_coalesce *coal)
 {
-	struct net_dim_cq_moder *rx_moder, *tx_moder;
+	struct dim_cq_moder *rx_moder, *tx_moder;
 
 	if (!MLX5_CAP_GEN(priv->mdev, cq_moderation))
 		return -EOPNOTSUPP;
@@ -521,7 +521,7 @@ mlx5e_set_priv_channels_coalesce(struct mlx5e_priv *priv, struct ethtool_coalesc
 int mlx5e_ethtool_set_coalesce(struct mlx5e_priv *priv,
 			       struct ethtool_coalesce *coal)
 {
-	struct net_dim_cq_moder *rx_moder, *tx_moder;
+	struct dim_cq_moder *rx_moder, *tx_moder;
 	struct mlx5_core_dev *mdev = priv->mdev;
 	struct mlx5e_channels new_channels = {};
 	int err = 0;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 5e40db8f92e6..4789735b8c7f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -586,11 +586,11 @@ static int mlx5e_alloc_rq(struct mlx5e_channel *c,
 
 	switch (params->rx_cq_moderation.cq_period_mode) {
 	case MLX5_CQ_PERIOD_MODE_START_FROM_CQE:
-		rq->dim.mode = NET_DIM_CQ_PERIOD_MODE_START_FROM_CQE;
+		rq->dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_CQE;
 		break;
 	case MLX5_CQ_PERIOD_MODE_START_FROM_EQE:
 	default:
-		rq->dim.mode = NET_DIM_CQ_PERIOD_MODE_START_FROM_EQE;
+		rq->dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE;
 	}
 
 	rq->page_cache.head = 0;
@@ -1568,7 +1568,7 @@ static void mlx5e_destroy_cq(struct mlx5e_cq *cq)
 }
 
 static int mlx5e_open_cq(struct mlx5e_channel *c,
-			 struct net_dim_cq_moder moder,
+			 struct dim_cq_moder moder,
 			 struct mlx5e_cq_param *param,
 			 struct mlx5e_cq *cq)
 {
@@ -1773,7 +1773,7 @@ static int mlx5e_open_channel(struct mlx5e_priv *priv, int ix,
 			      struct mlx5e_channel **cp)
 {
 	int cpu = cpumask_first(mlx5_comp_irq_get_affinity_mask(priv->mdev, ix));
-	struct net_dim_cq_moder icocq_moder = {0, 0};
+	struct dim_cq_moder icocq_moder = {0, 0};
 	struct net_device *netdev = priv->netdev;
 	struct mlx5e_channel *c;
 	unsigned int irq;
@@ -2150,7 +2150,7 @@ static void mlx5e_build_ico_cq_param(struct mlx5e_priv *priv,
 
 	mlx5e_build_common_cq_param(priv, param);
 
-	param->cq_period_mode = NET_DIM_CQ_PERIOD_MODE_START_FROM_EQE;
+	param->cq_period_mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE;
 }
 
 static void mlx5e_build_icosq_param(struct mlx5e_priv *priv,
@@ -4418,9 +4418,9 @@ static bool slow_pci_heuristic(struct mlx5_core_dev *mdev)
 		link_speed > MLX5E_SLOW_PCI_RATIO * pci_bw;
 }
 
-static struct net_dim_cq_moder mlx5e_get_def_tx_moderation(u8 cq_period_mode)
+static struct dim_cq_moder mlx5e_get_def_tx_moderation(u8 cq_period_mode)
 {
-	struct net_dim_cq_moder moder;
+	struct dim_cq_moder moder;
 
 	moder.cq_period_mode = cq_period_mode;
 	moder.pkts = MLX5E_PARAMS_DEFAULT_TX_CQ_MODERATION_PKTS;
@@ -4431,9 +4431,9 @@ static struct net_dim_cq_moder mlx5e_get_def_tx_moderation(u8 cq_period_mode)
 	return moder;
 }
 
-static struct net_dim_cq_moder mlx5e_get_def_rx_moderation(u8 cq_period_mode)
+static struct dim_cq_moder mlx5e_get_def_rx_moderation(u8 cq_period_mode)
 {
-	struct net_dim_cq_moder moder;
+	struct dim_cq_moder moder;
 
 	moder.cq_period_mode = cq_period_mode;
 	moder.pkts = MLX5E_PARAMS_DEFAULT_RX_CQ_MODERATION_PKTS;
@@ -4447,8 +4447,8 @@ static struct net_dim_cq_moder mlx5e_get_def_rx_moderation(u8 cq_period_mode)
 static u8 mlx5_to_net_dim_cq_period_mode(u8 cq_period_mode)
 {
 	return cq_period_mode == MLX5_CQ_PERIOD_MODE_START_FROM_CQE ?
-		NET_DIM_CQ_PERIOD_MODE_START_FROM_CQE :
-		NET_DIM_CQ_PERIOD_MODE_START_FROM_EQE;
+		DIM_CQ_PERIOD_MODE_START_FROM_CQE :
+		DIM_CQ_PERIOD_MODE_START_FROM_EQE;
 }
 
 void mlx5e_set_tx_cq_mode_params(struct mlx5e_params *params, u8 cq_period_mode)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
index f9862bf75491..e6c434efbd46 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_txrx.c
@@ -48,26 +48,24 @@ static inline bool mlx5e_channel_no_affinity_change(struct mlx5e_channel *c)
 static void mlx5e_handle_tx_dim(struct mlx5e_txqsq *sq)
 {
 	struct mlx5e_sq_stats *stats = sq->stats;
-	struct net_dim_sample dim_sample;
+	struct dim_sample dim_sample;
 
 	if (unlikely(!test_bit(MLX5E_SQ_STATE_AM, &sq->state)))
 		return;
 
-	net_dim_sample(sq->cq.event_ctr, stats->packets, stats->bytes,
-		       &dim_sample);
+	dim_update_sample(sq->cq.event_ctr, stats->packets, stats->bytes, &dim_sample);
 	net_dim(&sq->dim, dim_sample);
 }
 
 static void mlx5e_handle_rx_dim(struct mlx5e_rq *rq)
 {
 	struct mlx5e_rq_stats *stats = rq->stats;
-	struct net_dim_sample dim_sample;
+	struct dim_sample dim_sample;
 
 	if (unlikely(!test_bit(MLX5E_RQ_STATE_AM, &rq->state)))
 		return;
 
-	net_dim_sample(rq->cq.event_ctr, stats->packets, stats->bytes,
-		       &dim_sample);
+	dim_update_sample(rq->cq.event_ctr, stats->packets, stats->bytes, &dim_sample);
 	net_dim(&rq->dim, dim_sample);
 }