From 15619e722b16aaa40f942b93631aa92581a7b393 Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:26 +0300
Subject: [PATCH 01/11] net: ena: add intr_moder_rx_interval to struct
 ena_com_dev and use it

Add intr_moder_rx_interval to struct ena_com_dev and use it as the
location where the interrupt moderation rx interval is saved, instead
of the interrupt moderation table.

This is done as a first step before removing the old interrupt moderation
code.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_com.c    | 20 ++++----------------
 drivers/net/ethernet/amazon/ena/ena_com.h    |  8 +++++++-
 drivers/net/ethernet/amazon/ena/ena_netdev.c |  3 ++-
 3 files changed, 13 insertions(+), 18 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
index 911a2e7a375a..4144936bf8a2 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -1297,9 +1297,6 @@ static int ena_com_init_interrupt_moderation_table(struct ena_com_dev *ena_dev)
 static void ena_com_update_intr_delay_resolution(struct ena_com_dev *ena_dev,
 						 u16 intr_delay_resolution)
 {
-	struct ena_intr_moder_entry *intr_moder_tbl = ena_dev->intr_moder_tbl;
-	unsigned int i;
-
 	if (!intr_delay_resolution) {
 		pr_err("Illegal intr_delay_resolution provided. Going to use default 1 usec resolution\n");
 		intr_delay_resolution = 1;
@@ -1307,8 +1304,7 @@ static void ena_com_update_intr_delay_resolution(struct ena_com_dev *ena_dev,
 	ena_dev->intr_delay_resolution = intr_delay_resolution;
 
 	/* update Rx */
-	for (i = 0; i < ENA_INTR_MAX_NUM_OF_LEVELS; i++)
-		intr_moder_tbl[i].intr_moder_interval /= intr_delay_resolution;
+	ena_dev->intr_moder_rx_interval /= intr_delay_resolution;
 
 	/* update Tx */
 	ena_dev->intr_moder_tx_interval /= intr_delay_resolution;
@@ -2798,11 +2794,8 @@ int ena_com_update_nonadaptive_moderation_interval_rx(struct ena_com_dev *ena_de
 		return -EFAULT;
 	}
 
-	/* We use LOWEST entry of moderation table for storing
-	 * nonadaptive interrupt coalescing values
-	 */
-	ena_dev->intr_moder_tbl[ENA_INTR_MODER_LOWEST].intr_moder_interval =
-		rx_coalesce_usecs / ena_dev->intr_delay_resolution;
+	ena_dev->intr_moder_rx_interval = rx_coalesce_usecs /
+		ena_dev->intr_delay_resolution;
 
 	return 0;
 }
@@ -2907,12 +2900,7 @@ unsigned int ena_com_get_nonadaptive_moderation_interval_tx(struct ena_com_dev *
 
 unsigned int ena_com_get_nonadaptive_moderation_interval_rx(struct ena_com_dev *ena_dev)
 {
-	struct ena_intr_moder_entry *intr_moder_tbl = ena_dev->intr_moder_tbl;
-
-	if (intr_moder_tbl)
-		return intr_moder_tbl[ENA_INTR_MODER_LOWEST].intr_moder_interval;
-
-	return 0;
+	return ena_dev->intr_moder_rx_interval;
 }
 
 void ena_com_init_intr_moderation_entry(struct ena_com_dev *ena_dev,
diff --git a/drivers/net/ethernet/amazon/ena/ena_com.h b/drivers/net/ethernet/amazon/ena/ena_com.h
index 0d3664fe260d..baeefc6af4f3 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.h
+++ b/drivers/net/ethernet/amazon/ena/ena_com.h
@@ -93,7 +93,7 @@
 #define ENA_INTR_HIGHEST_BYTES          (192 * 1024)
 
 #define ENA_INTR_INITIAL_TX_INTERVAL_USECS		196
-#define ENA_INTR_INITIAL_RX_INTERVAL_USECS		4
+#define ENA_INTR_INITIAL_RX_INTERVAL_USECS		0
 #define ENA_INTR_DELAY_OLD_VALUE_WEIGHT			6
 #define ENA_INTR_DELAY_NEW_VALUE_WEIGHT			4
 #define ENA_INTR_MODER_LEVEL_STRIDE			2
@@ -376,7 +376,13 @@ struct ena_com_dev {
 	struct ena_host_attribute host_attr;
 	bool adaptive_coalescing;
 	u16 intr_delay_resolution;
+
+	/* interrupt moderation intervals are in usec divided by
+	 * intr_delay_resolution, which is supplied by the device.
+	 */
 	u32 intr_moder_tx_interval;
+	u32 intr_moder_rx_interval;
+
 	struct ena_intr_moder_entry *intr_moder_tbl;
 
 	struct ena_com_llq_info llq_info;
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index 664e3ed97ea9..233b252ceb9e 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -3485,10 +3485,11 @@ static int ena_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	calc_queue_ctx.get_feat_ctx = &get_feat_ctx;
 	calc_queue_ctx.pdev = pdev;
 
-	/* initial Tx interrupt delay, Assumes 1 usec granularity.
+	/* Initial Tx and RX interrupt delay. Assumes 1 usec granularity.
 	* Updated during device initialization with the real granularity
 	*/
 	ena_dev->intr_moder_tx_interval = ENA_INTR_INITIAL_TX_INTERVAL_USECS;
+	ena_dev->intr_moder_rx_interval = ENA_INTR_INITIAL_RX_INTERVAL_USECS;
 	io_queue_num = ena_calc_io_queue_num(pdev, ena_dev, &get_feat_ctx);
 	rc = ena_calc_queue_size(&calc_queue_ctx);
 	if (rc || io_queue_num <= 0) {

From 282faf61a053be43910fcc42d86ecf16c0d30123 Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:27 +0300
Subject: [PATCH 02/11] net: ena: switch to dim algorithm for rx adaptive
 interrupt moderation

Use the dim library for the rx adaptive interrupt moderation implementation

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_com.c    |  4 +-
 drivers/net/ethernet/amazon/ena/ena_netdev.c | 53 +++++++++++++-------
 drivers/net/ethernet/amazon/ena/ena_netdev.h |  3 ++
 3 files changed, 40 insertions(+), 20 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
index 4144936bf8a2..f3c67c27c19c 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -2839,9 +2839,7 @@ int ena_com_init_interrupt_moderation(struct ena_com_dev *ena_dev)
 	delay_resolution = get_resp.u.intr_moderation.intr_delay_resolution;
 	ena_com_update_intr_delay_resolution(ena_dev, delay_resolution);
 
-	/* Disable adaptive moderation by default - can be enabled from
-	 * ethtool
-	 */
+	/* Disable adaptive moderation by default - can be enabled later */
 	ena_com_disable_adaptive_moderation(ena_dev);
 
 	return 0;
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index 233b252ceb9e..cdcc169b87fa 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -196,6 +196,7 @@ static void ena_init_io_rings(struct ena_adapter *adapter)
 		rxr->smoothed_interval =
 			ena_com_get_nonadaptive_moderation_interval_rx(ena_dev);
 		rxr->empty_rx_queue = 0;
+		adapter->ena_napi[i].dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE;
 	}
 }
 
@@ -712,6 +713,7 @@ static void ena_destroy_all_rx_queues(struct ena_adapter *adapter)
 
 	for (i = 0; i < adapter->num_queues; i++) {
 		ena_qid = ENA_IO_RXQ_IDX(i);
+		cancel_work_sync(&adapter->ena_napi[i].dim.work);
 		ena_com_destroy_io_queue(adapter->ena_dev, ena_qid);
 	}
 }
@@ -1155,23 +1157,35 @@ error:
 	return 0;
 }
 
-void ena_adjust_intr_moderation(struct ena_ring *rx_ring,
-				       struct ena_ring *tx_ring)
+static void ena_dim_work(struct work_struct *w)
 {
-	/* We apply adaptive moderation on Rx path only.
-	 * Tx uses static interrupt moderation.
-	 */
-	ena_com_calculate_interrupt_delay(rx_ring->ena_dev,
-					  rx_ring->per_napi_packets,
-					  rx_ring->per_napi_bytes,
-					  &rx_ring->smoothed_interval,
-					  &rx_ring->moder_tbl_idx);
+	struct dim *dim = container_of(w, struct dim, work);
+	struct dim_cq_moder cur_moder =
+		net_dim_get_rx_moderation(dim->mode, dim->profile_ix);
+	struct ena_napi *ena_napi = container_of(dim, struct ena_napi, dim);
+
+	ena_napi->rx_ring->smoothed_interval = cur_moder.usec;
+	dim->state = DIM_START_MEASURE;
+}
+
+static void ena_adjust_adaptive_rx_intr_moderation(struct ena_napi *ena_napi)
+{
+	struct dim_sample dim_sample;
+	struct ena_ring *rx_ring = ena_napi->rx_ring;
+
+	if (!rx_ring->per_napi_packets)
+		return;
+
+	rx_ring->non_empty_napi_events++;
+
+	dim_update_sample(rx_ring->non_empty_napi_events,
+			  rx_ring->rx_stats.cnt,
+			  rx_ring->rx_stats.bytes,
+			  &dim_sample);
+
+	net_dim(&ena_napi->dim, dim_sample);
 
-	/* Reset per napi packets/bytes */
-	tx_ring->per_napi_packets = 0;
-	tx_ring->per_napi_bytes = 0;
 	rx_ring->per_napi_packets = 0;
-	rx_ring->per_napi_bytes = 0;
 }
 
 static void ena_unmask_interrupt(struct ena_ring *tx_ring,
@@ -1260,9 +1274,11 @@ static int ena_io_poll(struct napi_struct *napi, int budget)
 		 * from the interrupt context (vs from sk_busy_loop)
 		 */
 		if (napi_complete_done(napi, rx_work_done)) {
-			/* Tx and Rx share the same interrupt vector */
+			/* We apply adaptive moderation on Rx path only.
+			 * Tx uses static interrupt moderation.
+			 */
 			if (ena_com_get_adaptive_moderation_enabled(rx_ring->ena_dev))
-				ena_adjust_intr_moderation(rx_ring, tx_ring);
+				ena_adjust_adaptive_rx_intr_moderation(ena_napi);
 
 			ena_unmask_interrupt(tx_ring, rx_ring);
 		}
@@ -1740,13 +1756,16 @@ static int ena_create_all_io_rx_queues(struct ena_adapter *adapter)
 		rc = ena_create_io_rx_queue(adapter, i);
 		if (rc)
 			goto create_err;
+		INIT_WORK(&adapter->ena_napi[i].dim.work, ena_dim_work);
 	}
 
 	return 0;
 
 create_err:
-	while (i--)
+	while (i--) {
+		cancel_work_sync(&adapter->ena_napi[i].dim.work);
 		ena_com_destroy_io_queue(ena_dev, ENA_IO_RXQ_IDX(i));
+	}
 
 	return rc;
 }
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h
index efbcffd22215..f67ecab3389a 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.h
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h
@@ -34,6 +34,7 @@
 #define ENA_H
 
 #include <linux/bitops.h>
+#include <linux/dim.h>
 #include <linux/etherdevice.h>
 #include <linux/inetdevice.h>
 #include <linux/interrupt.h>
@@ -153,6 +154,7 @@ struct ena_napi {
 	struct ena_ring *tx_ring;
 	struct ena_ring *rx_ring;
 	u32 qid;
+	struct dim dim;
 };
 
 struct ena_calc_queue_size_ctx {
@@ -280,6 +282,7 @@ struct ena_ring {
 	u32  per_napi_packets;
 	u32  per_napi_bytes;
 	enum ena_intr_moder_level moder_tbl_idx;
+	u16 non_empty_napi_events;
 	struct u64_stats_sync syncp;
 	union {
 		struct ena_stats_tx tx_stats;

From b3db86dc4b82ffc63e33c78dafc09d5c78ac4fe4 Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:28 +0300
Subject: [PATCH 03/11] net: ena: reimplement set/get_coalesce()

1. Remove old adaptive interrupt moderation code from set/get_coalesce()
2. Add ena_update_rx_rings_intr_moderation() function for updating
   nonadaptive interrupt moderation intervals similarly to
   ena_update_tx_rings_intr_moderation().
3. Remove checks of multiple unsupported received interrupt coalescing
   parameters. This makes code cleaner and cancels the need to update
   it every time a new coalescing parameter is invented.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_ethtool.c | 82 ++++++-------------
 1 file changed, 25 insertions(+), 57 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_ethtool.c b/drivers/net/ethernet/amazon/ena/ena_ethtool.c
index b997c3ce9e2b..0f90e2296630 100644
--- a/drivers/net/ethernet/amazon/ena/ena_ethtool.c
+++ b/drivers/net/ethernet/amazon/ena/ena_ethtool.c
@@ -305,7 +305,6 @@ static int ena_get_coalesce(struct net_device *net_dev,
 {
 	struct ena_adapter *adapter = netdev_priv(net_dev);
 	struct ena_com_dev *ena_dev = adapter->ena_dev;
-	struct ena_intr_moder_entry intr_moder_entry;
 
 	if (!ena_com_interrupt_moderation_supported(ena_dev)) {
 		/* the devie doesn't support interrupt moderation */
@@ -314,23 +313,12 @@ static int ena_get_coalesce(struct net_device *net_dev,
 	coalesce->tx_coalesce_usecs =
 		ena_com_get_nonadaptive_moderation_interval_tx(ena_dev) /
 			ena_dev->intr_delay_resolution;
-	if (!ena_com_get_adaptive_moderation_enabled(ena_dev)) {
+
+	if (!ena_com_get_adaptive_moderation_enabled(ena_dev))
 		coalesce->rx_coalesce_usecs =
 			ena_com_get_nonadaptive_moderation_interval_rx(ena_dev)
 			/ ena_dev->intr_delay_resolution;
-	} else {
-		ena_com_get_intr_moderation_entry(adapter->ena_dev, ENA_INTR_MODER_LOWEST, &intr_moder_entry);
-		coalesce->rx_coalesce_usecs_low = intr_moder_entry.intr_moder_interval;
-		coalesce->rx_max_coalesced_frames_low = intr_moder_entry.pkts_per_interval;
 
-		ena_com_get_intr_moderation_entry(adapter->ena_dev, ENA_INTR_MODER_MID, &intr_moder_entry);
-		coalesce->rx_coalesce_usecs = intr_moder_entry.intr_moder_interval;
-		coalesce->rx_max_coalesced_frames = intr_moder_entry.pkts_per_interval;
-
-		ena_com_get_intr_moderation_entry(adapter->ena_dev, ENA_INTR_MODER_HIGHEST, &intr_moder_entry);
-		coalesce->rx_coalesce_usecs_high = intr_moder_entry.intr_moder_interval;
-		coalesce->rx_max_coalesced_frames_high = intr_moder_entry.pkts_per_interval;
-	}
 	coalesce->use_adaptive_rx_coalesce =
 		ena_com_get_adaptive_moderation_enabled(ena_dev);
 
@@ -348,12 +336,22 @@ static void ena_update_tx_rings_intr_moderation(struct ena_adapter *adapter)
 		adapter->tx_ring[i].smoothed_interval = val;
 }
 
+static void ena_update_rx_rings_intr_moderation(struct ena_adapter *adapter)
+{
+	unsigned int val;
+	int i;
+
+	val = ena_com_get_nonadaptive_moderation_interval_rx(adapter->ena_dev);
+
+	for (i = 0; i < adapter->num_queues; i++)
+		adapter->rx_ring[i].smoothed_interval = val;
+}
+
 static int ena_set_coalesce(struct net_device *net_dev,
 			    struct ethtool_coalesce *coalesce)
 {
 	struct ena_adapter *adapter = netdev_priv(net_dev);
 	struct ena_com_dev *ena_dev = adapter->ena_dev;
-	struct ena_intr_moder_entry intr_moder_entry;
 	int rc;
 
 	if (!ena_com_interrupt_moderation_supported(ena_dev)) {
@@ -361,22 +359,6 @@ static int ena_set_coalesce(struct net_device *net_dev,
 		return -EOPNOTSUPP;
 	}
 
-	if (coalesce->rx_coalesce_usecs_irq ||
-	    coalesce->rx_max_coalesced_frames_irq ||
-	    coalesce->tx_coalesce_usecs_irq ||
-	    coalesce->tx_max_coalesced_frames ||
-	    coalesce->tx_max_coalesced_frames_irq ||
-	    coalesce->stats_block_coalesce_usecs ||
-	    coalesce->use_adaptive_tx_coalesce ||
-	    coalesce->pkt_rate_low ||
-	    coalesce->tx_coalesce_usecs_low ||
-	    coalesce->tx_max_coalesced_frames_low ||
-	    coalesce->pkt_rate_high ||
-	    coalesce->tx_coalesce_usecs_high ||
-	    coalesce->tx_max_coalesced_frames_high ||
-	    coalesce->rate_sample_interval)
-		return -EINVAL;
-
 	rc = ena_com_update_nonadaptive_moderation_interval_tx(ena_dev,
 							       coalesce->tx_coalesce_usecs);
 	if (rc)
@@ -384,37 +366,23 @@ static int ena_set_coalesce(struct net_device *net_dev,
 
 	ena_update_tx_rings_intr_moderation(adapter);
 
-	if (ena_com_get_adaptive_moderation_enabled(ena_dev)) {
-		if (!coalesce->use_adaptive_rx_coalesce) {
-			ena_com_disable_adaptive_moderation(ena_dev);
-			rc = ena_com_update_nonadaptive_moderation_interval_rx(ena_dev,
-									       coalesce->rx_coalesce_usecs);
-			return rc;
-		}
-	} else { /* was in non-adaptive mode */
-		if (coalesce->use_adaptive_rx_coalesce) {
+	if (coalesce->use_adaptive_rx_coalesce) {
+		if (!ena_com_get_adaptive_moderation_enabled(ena_dev))
 			ena_com_enable_adaptive_moderation(ena_dev);
-		} else {
-			rc = ena_com_update_nonadaptive_moderation_interval_rx(ena_dev,
-									       coalesce->rx_coalesce_usecs);
-			return rc;
-		}
+		return 0;
 	}
 
-	intr_moder_entry.intr_moder_interval = coalesce->rx_coalesce_usecs_low;
-	intr_moder_entry.pkts_per_interval = coalesce->rx_max_coalesced_frames_low;
-	intr_moder_entry.bytes_per_interval = ENA_INTR_BYTE_COUNT_NOT_SUPPORTED;
-	ena_com_init_intr_moderation_entry(adapter->ena_dev, ENA_INTR_MODER_LOWEST, &intr_moder_entry);
+	rc = ena_com_update_nonadaptive_moderation_interval_rx(ena_dev,
+							       coalesce->rx_coalesce_usecs);
+	if (rc)
+		return rc;
 
-	intr_moder_entry.intr_moder_interval = coalesce->rx_coalesce_usecs;
-	intr_moder_entry.pkts_per_interval = coalesce->rx_max_coalesced_frames;
-	intr_moder_entry.bytes_per_interval = ENA_INTR_BYTE_COUNT_NOT_SUPPORTED;
-	ena_com_init_intr_moderation_entry(adapter->ena_dev, ENA_INTR_MODER_MID, &intr_moder_entry);
+	ena_update_rx_rings_intr_moderation(adapter);
 
-	intr_moder_entry.intr_moder_interval = coalesce->rx_coalesce_usecs_high;
-	intr_moder_entry.pkts_per_interval = coalesce->rx_max_coalesced_frames_high;
-	intr_moder_entry.bytes_per_interval = ENA_INTR_BYTE_COUNT_NOT_SUPPORTED;
-	ena_com_init_intr_moderation_entry(adapter->ena_dev, ENA_INTR_MODER_HIGHEST, &intr_moder_entry);
+	if (!coalesce->use_adaptive_rx_coalesce) {
+		if (ena_com_get_adaptive_moderation_enabled(ena_dev))
+			ena_com_disable_adaptive_moderation(ena_dev);
+	}
 
 	return 0;
 }

From bd21b0cc3a63d1c658b230db084b0f392b78cab2 Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:29 +0300
Subject: [PATCH 04/11] net: ena: enable the interrupt_moderation in
 driver_supported_features

Add driver_supported_features to host_host info which is a new API used to
communicate to the device which features are supported by the driver.

Add the interrupt_moderation bit to host_info->driver_supported_features
and enable it to signal the device that this driver supports interrupt
moderation properly.

Reserved bits are for features implemented in the future

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_admin_defs.h | 8 ++++++++
 drivers/net/ethernet/amazon/ena/ena_netdev.c     | 3 +++
 2 files changed, 11 insertions(+)

diff --git a/drivers/net/ethernet/amazon/ena/ena_admin_defs.h b/drivers/net/ethernet/amazon/ena/ena_admin_defs.h
index d19f2ecf8e84..8baf847e8622 100644
--- a/drivers/net/ethernet/amazon/ena/ena_admin_defs.h
+++ b/drivers/net/ethernet/amazon/ena/ena_admin_defs.h
@@ -808,6 +808,12 @@ struct ena_admin_host_info {
 	u16 num_cpus;
 
 	u16 reserved;
+
+	/* 1 :0 : reserved
+	 * 2 : interrupt_moderation
+	 * 31:3 : reserved
+	 */
+	u32 driver_supported_features;
 };
 
 struct ena_admin_rss_ind_table_entry {
@@ -1110,6 +1116,8 @@ struct ena_admin_ena_mmio_req_read_less_resp {
 #define ENA_ADMIN_HOST_INFO_DEVICE_MASK                     GENMASK(7, 3)
 #define ENA_ADMIN_HOST_INFO_BUS_SHIFT                       8
 #define ENA_ADMIN_HOST_INFO_BUS_MASK                        GENMASK(15, 8)
+#define ENA_ADMIN_HOST_INFO_INTERRUPT_MODERATION_SHIFT      2
+#define ENA_ADMIN_HOST_INFO_INTERRUPT_MODERATION_MASK       BIT(2)
 
 /* aenq_common_desc */
 #define ENA_ADMIN_AENQ_COMMON_DESC_PHASE_MASK               BIT(0)
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index cdcc169b87fa..f19736493c01 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -2438,6 +2438,9 @@ static void ena_config_host_info(struct ena_com_dev *ena_dev,
 		("K"[0] << ENA_ADMIN_HOST_INFO_MODULE_TYPE_SHIFT);
 	host_info->num_cpus = num_online_cpus();
 
+	host_info->driver_supported_features =
+		ENA_ADMIN_HOST_INFO_INTERRUPT_MODERATION_MASK;
+
 	rc = ena_com_set_host_attributes(ena_dev);
 	if (rc) {
 		if (rc == -EOPNOTSUPP)

From 57e3a5f24bb5bf265988e973a911845abcbf6a00 Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:30 +0300
Subject: [PATCH 05/11] net: ena: remove code duplication in
 ena_com_update_nonadaptive_moderation_interval _*()

Remove code duplication in:
ena_com_update_nonadaptive_moderation_interval_tx()
ena_com_update_nonadaptive_moderation_interval_rx()
functions.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_com.c | 30 ++++++++++++-----------
 1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
index f3c67c27c19c..bbb59fd220a1 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -2772,32 +2772,34 @@ bool ena_com_interrupt_moderation_supported(struct ena_com_dev *ena_dev)
 						  ENA_ADMIN_INTERRUPT_MODERATION);
 }
 
-int ena_com_update_nonadaptive_moderation_interval_tx(struct ena_com_dev *ena_dev,
-						      u32 tx_coalesce_usecs)
+static int ena_com_update_nonadaptive_moderation_interval(u32 coalesce_usecs,
+							  u32 intr_delay_resolution,
+							  u32 *intr_moder_interval)
 {
-	if (!ena_dev->intr_delay_resolution) {
+	if (!intr_delay_resolution) {
 		pr_err("Illegal interrupt delay granularity value\n");
 		return -EFAULT;
 	}
 
-	ena_dev->intr_moder_tx_interval = tx_coalesce_usecs /
-		ena_dev->intr_delay_resolution;
+	*intr_moder_interval = coalesce_usecs / intr_delay_resolution;
 
 	return 0;
 }
 
+int ena_com_update_nonadaptive_moderation_interval_tx(struct ena_com_dev *ena_dev,
+						      u32 tx_coalesce_usecs)
+{
+	return ena_com_update_nonadaptive_moderation_interval(tx_coalesce_usecs,
+							      ena_dev->intr_delay_resolution,
+							      &ena_dev->intr_moder_tx_interval);
+}
+
 int ena_com_update_nonadaptive_moderation_interval_rx(struct ena_com_dev *ena_dev,
 						      u32 rx_coalesce_usecs)
 {
-	if (!ena_dev->intr_delay_resolution) {
-		pr_err("Illegal interrupt delay granularity value\n");
-		return -EFAULT;
-	}
-
-	ena_dev->intr_moder_rx_interval = rx_coalesce_usecs /
-		ena_dev->intr_delay_resolution;
-
-	return 0;
+	return ena_com_update_nonadaptive_moderation_interval(rx_coalesce_usecs,
+							      ena_dev->intr_delay_resolution,
+							      &ena_dev->intr_moder_rx_interval);
 }
 
 void ena_com_destroy_interrupt_moderation(struct ena_com_dev *ena_dev)

From 242d81fd3dd9f301b0c20564aafec8efdb2bbe5b Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:31 +0300
Subject: [PATCH 06/11] net: ena: remove old adaptive interrupt moderation code
 from ena_netdev

1. Out of the fields {per_napi_bytes, per_napi_packets} in struct ena_ring,
   only rx_ring->per_napi_packets are used to determine if napi did work
   for dim.
   This commit removes all other uses of these fields.
2. Remove ena_ring->moder_tbl_idx, which is not used by dim.
3. Remove all calls to ena_com_destroy_interrupt_moderation(), since all it
   did was to destroy the interrupt moderation table, which is removed as
   part of removing old interrupt moderation code.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_netdev.c | 8 --------
 drivers/net/ethernet/amazon/ena/ena_netdev.h | 2 --
 2 files changed, 10 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index f19736493c01..1d8855ab8624 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -158,7 +158,6 @@ static void ena_init_io_rings_common(struct ena_adapter *adapter,
 	ring->adapter = adapter;
 	ring->ena_dev = adapter->ena_dev;
 	ring->per_napi_packets = 0;
-	ring->per_napi_bytes = 0;
 	ring->cpu = 0;
 	ring->first_interrupt = false;
 	ring->no_interrupt_event_cnt = 0;
@@ -834,9 +833,6 @@ static int ena_clean_tx_irq(struct ena_ring *tx_ring, u32 budget)
 		__netif_tx_unlock(txq);
 	}
 
-	tx_ring->per_napi_bytes += tx_bytes;
-	tx_ring->per_napi_packets += tx_pkts;
-
 	return tx_pkts;
 }
 
@@ -1120,7 +1116,6 @@ static int ena_clean_rx_irq(struct ena_ring *rx_ring, struct napi_struct *napi,
 	} while (likely(res_budget));
 
 	work_done = budget - res_budget;
-	rx_ring->per_napi_bytes += total_len;
 	rx_ring->per_napi_packets += work_done;
 	u64_stats_update_begin(&rx_ring->syncp);
 	rx_ring->rx_stats.bytes += total_len;
@@ -3641,7 +3636,6 @@ err_free_msix:
 	ena_free_mgmnt_irq(adapter);
 	ena_disable_msix(adapter);
 err_worker_destroy:
-	ena_com_destroy_interrupt_moderation(ena_dev);
 	del_timer(&adapter->timer_service);
 err_netdev_destroy:
 	free_netdev(netdev);
@@ -3702,8 +3696,6 @@ static void ena_remove(struct pci_dev *pdev)
 
 	pci_disable_device(pdev);
 
-	ena_com_destroy_interrupt_moderation(ena_dev);
-
 	vfree(ena_dev);
 }
 
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h
index f67ecab3389a..e9450991ab74 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.h
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h
@@ -280,8 +280,6 @@ struct ena_ring {
 	struct ena_com_rx_buf_info ena_bufs[ENA_PKT_MAX_BUFS];
 	u32  smoothed_interval;
 	u32  per_napi_packets;
-	u32  per_napi_bytes;
-	enum ena_intr_moder_level moder_tbl_idx;
 	u16 non_empty_napi_events;
 	struct u64_stats_sync syncp;
 	union {

From 64d1fb9dfc6c5d8589312fa847fee14ec14ee12b Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:32 +0300
Subject: [PATCH 07/11] net: ena: remove ena_restore_ethtool_params() and
 relevant fields

Deleted unused 4 fields from struct ena_adapter and their only user
ena_restore_ethtool_params().

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_netdev.c | 10 ----------
 drivers/net/ethernet/amazon/ena/ena_netdev.h |  3 ---
 2 files changed, 13 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index 1d8855ab8624..8b9f8b90e525 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -1563,14 +1563,6 @@ static void ena_napi_enable_all(struct ena_adapter *adapter)
 		napi_enable(&adapter->ena_napi[i].napi);
 }
 
-static void ena_restore_ethtool_params(struct ena_adapter *adapter)
-{
-	adapter->tx_usecs = 0;
-	adapter->rx_usecs = 0;
-	adapter->tx_frames = 1;
-	adapter->rx_frames = 1;
-}
-
 /* Configure the Rx forwarding */
 static int ena_rss_configure(struct ena_adapter *adapter)
 {
@@ -1620,8 +1612,6 @@ static int ena_up_complete(struct ena_adapter *adapter)
 	/* enable transmits */
 	netif_tx_start_all_queues(adapter->netdev);
 
-	ena_restore_ethtool_params(adapter);
-
 	ena_napi_enable_all(adapter);
 
 	return 0;
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h
index e9450991ab74..72ee51a82ec7 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.h
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h
@@ -330,9 +330,6 @@ struct ena_adapter {
 
 	u32 missing_tx_completion_threshold;
 
-	u32 tx_usecs, rx_usecs; /* interrupt moderation */
-	u32 tx_frames, rx_frames; /* interrupt moderation */
-
 	u32 requested_tx_ring_size;
 	u32 requested_rx_ring_size;
 

From 3ced8cbdf7ddb3160ffa714a91040dd18f39a12c Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:33 +0300
Subject: [PATCH 08/11] net: ena: remove all old adaptive rx interrupt
 moderation code from ena_com

Remove previous implementation of adaptive rx interrupt moderation
from ena_com files.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_com.c | 110 -----------------
 drivers/net/ethernet/amazon/ena/ena_com.h | 142 ----------------------
 2 files changed, 252 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
index bbb59fd220a1..621b747f062b 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -1278,22 +1278,6 @@ static int ena_com_ind_tbl_convert_from_device(struct ena_com_dev *ena_dev)
 	return 0;
 }
 
-static int ena_com_init_interrupt_moderation_table(struct ena_com_dev *ena_dev)
-{
-	size_t size;
-
-	size = sizeof(struct ena_intr_moder_entry) * ENA_INTR_MAX_NUM_OF_LEVELS;
-
-	ena_dev->intr_moder_tbl =
-		devm_kzalloc(ena_dev->dmadev, size, GFP_KERNEL);
-	if (!ena_dev->intr_moder_tbl)
-		return -ENOMEM;
-
-	ena_com_config_default_interrupt_moderation_table(ena_dev);
-
-	return 0;
-}
-
 static void ena_com_update_intr_delay_resolution(struct ena_com_dev *ena_dev,
 						 u16 intr_delay_resolution)
 {
@@ -2802,13 +2786,6 @@ int ena_com_update_nonadaptive_moderation_interval_rx(struct ena_com_dev *ena_de
 							      &ena_dev->intr_moder_rx_interval);
 }
 
-void ena_com_destroy_interrupt_moderation(struct ena_com_dev *ena_dev)
-{
-	if (ena_dev->intr_moder_tbl)
-		devm_kfree(ena_dev->dmadev, ena_dev->intr_moder_tbl);
-	ena_dev->intr_moder_tbl = NULL;
-}
-
 int ena_com_init_interrupt_moderation(struct ena_com_dev *ena_dev)
 {
 	struct ena_admin_get_feat_resp get_resp;
@@ -2833,10 +2810,6 @@ int ena_com_init_interrupt_moderation(struct ena_com_dev *ena_dev)
 		return rc;
 	}
 
-	rc = ena_com_init_interrupt_moderation_table(ena_dev);
-	if (rc)
-		goto err;
-
 	/* if moderation is supported by device we set adaptive moderation */
 	delay_resolution = get_resp.u.intr_moderation.intr_delay_resolution;
 	ena_com_update_intr_delay_resolution(ena_dev, delay_resolution);
@@ -2845,52 +2818,6 @@ int ena_com_init_interrupt_moderation(struct ena_com_dev *ena_dev)
 	ena_com_disable_adaptive_moderation(ena_dev);
 
 	return 0;
-err:
-	ena_com_destroy_interrupt_moderation(ena_dev);
-	return rc;
-}
-
-void ena_com_config_default_interrupt_moderation_table(struct ena_com_dev *ena_dev)
-{
-	struct ena_intr_moder_entry *intr_moder_tbl = ena_dev->intr_moder_tbl;
-
-	if (!intr_moder_tbl)
-		return;
-
-	intr_moder_tbl[ENA_INTR_MODER_LOWEST].intr_moder_interval =
-		ENA_INTR_LOWEST_USECS;
-	intr_moder_tbl[ENA_INTR_MODER_LOWEST].pkts_per_interval =
-		ENA_INTR_LOWEST_PKTS;
-	intr_moder_tbl[ENA_INTR_MODER_LOWEST].bytes_per_interval =
-		ENA_INTR_LOWEST_BYTES;
-
-	intr_moder_tbl[ENA_INTR_MODER_LOW].intr_moder_interval =
-		ENA_INTR_LOW_USECS;
-	intr_moder_tbl[ENA_INTR_MODER_LOW].pkts_per_interval =
-		ENA_INTR_LOW_PKTS;
-	intr_moder_tbl[ENA_INTR_MODER_LOW].bytes_per_interval =
-		ENA_INTR_LOW_BYTES;
-
-	intr_moder_tbl[ENA_INTR_MODER_MID].intr_moder_interval =
-		ENA_INTR_MID_USECS;
-	intr_moder_tbl[ENA_INTR_MODER_MID].pkts_per_interval =
-		ENA_INTR_MID_PKTS;
-	intr_moder_tbl[ENA_INTR_MODER_MID].bytes_per_interval =
-		ENA_INTR_MID_BYTES;
-
-	intr_moder_tbl[ENA_INTR_MODER_HIGH].intr_moder_interval =
-		ENA_INTR_HIGH_USECS;
-	intr_moder_tbl[ENA_INTR_MODER_HIGH].pkts_per_interval =
-		ENA_INTR_HIGH_PKTS;
-	intr_moder_tbl[ENA_INTR_MODER_HIGH].bytes_per_interval =
-		ENA_INTR_HIGH_BYTES;
-
-	intr_moder_tbl[ENA_INTR_MODER_HIGHEST].intr_moder_interval =
-		ENA_INTR_HIGHEST_USECS;
-	intr_moder_tbl[ENA_INTR_MODER_HIGHEST].pkts_per_interval =
-		ENA_INTR_HIGHEST_PKTS;
-	intr_moder_tbl[ENA_INTR_MODER_HIGHEST].bytes_per_interval =
-		ENA_INTR_HIGHEST_BYTES;
 }
 
 unsigned int ena_com_get_nonadaptive_moderation_interval_tx(struct ena_com_dev *ena_dev)
@@ -2903,43 +2830,6 @@ unsigned int ena_com_get_nonadaptive_moderation_interval_rx(struct ena_com_dev *
 	return ena_dev->intr_moder_rx_interval;
 }
 
-void ena_com_init_intr_moderation_entry(struct ena_com_dev *ena_dev,
-					enum ena_intr_moder_level level,
-					struct ena_intr_moder_entry *entry)
-{
-	struct ena_intr_moder_entry *intr_moder_tbl = ena_dev->intr_moder_tbl;
-
-	if (level >= ENA_INTR_MAX_NUM_OF_LEVELS)
-		return;
-
-	intr_moder_tbl[level].intr_moder_interval = entry->intr_moder_interval;
-	if (ena_dev->intr_delay_resolution)
-		intr_moder_tbl[level].intr_moder_interval /=
-			ena_dev->intr_delay_resolution;
-	intr_moder_tbl[level].pkts_per_interval = entry->pkts_per_interval;
-
-	/* use hardcoded value until ethtool supports bytecount parameter */
-	if (entry->bytes_per_interval != ENA_INTR_BYTE_COUNT_NOT_SUPPORTED)
-		intr_moder_tbl[level].bytes_per_interval = entry->bytes_per_interval;
-}
-
-void ena_com_get_intr_moderation_entry(struct ena_com_dev *ena_dev,
-				       enum ena_intr_moder_level level,
-				       struct ena_intr_moder_entry *entry)
-{
-	struct ena_intr_moder_entry *intr_moder_tbl = ena_dev->intr_moder_tbl;
-
-	if (level >= ENA_INTR_MAX_NUM_OF_LEVELS)
-		return;
-
-	entry->intr_moder_interval = intr_moder_tbl[level].intr_moder_interval;
-	if (ena_dev->intr_delay_resolution)
-		entry->intr_moder_interval *= ena_dev->intr_delay_resolution;
-	entry->pkts_per_interval =
-	intr_moder_tbl[level].pkts_per_interval;
-	entry->bytes_per_interval = intr_moder_tbl[level].bytes_per_interval;
-}
-
 int ena_com_config_dev_mode(struct ena_com_dev *ena_dev,
 			    struct ena_admin_feature_llq_desc *llq_features,
 			    struct ena_llq_configurations *llq_default_cfg)
diff --git a/drivers/net/ethernet/amazon/ena/ena_com.h b/drivers/net/ethernet/amazon/ena/ena_com.h
index baeefc6af4f3..ddc2a8c50333 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.h
+++ b/drivers/net/ethernet/amazon/ena/ena_com.h
@@ -72,46 +72,13 @@
 /*****************************************************************************/
 /* ENA adaptive interrupt moderation settings */
 
-#define ENA_INTR_LOWEST_USECS           (0)
-#define ENA_INTR_LOWEST_PKTS            (3)
-#define ENA_INTR_LOWEST_BYTES           (2 * 1524)
-
-#define ENA_INTR_LOW_USECS              (32)
-#define ENA_INTR_LOW_PKTS               (12)
-#define ENA_INTR_LOW_BYTES              (16 * 1024)
-
-#define ENA_INTR_MID_USECS              (80)
-#define ENA_INTR_MID_PKTS               (48)
-#define ENA_INTR_MID_BYTES              (64 * 1024)
-
-#define ENA_INTR_HIGH_USECS             (128)
-#define ENA_INTR_HIGH_PKTS              (96)
-#define ENA_INTR_HIGH_BYTES             (128 * 1024)
-
-#define ENA_INTR_HIGHEST_USECS          (192)
-#define ENA_INTR_HIGHEST_PKTS           (128)
-#define ENA_INTR_HIGHEST_BYTES          (192 * 1024)
-
 #define ENA_INTR_INITIAL_TX_INTERVAL_USECS		196
 #define ENA_INTR_INITIAL_RX_INTERVAL_USECS		0
-#define ENA_INTR_DELAY_OLD_VALUE_WEIGHT			6
-#define ENA_INTR_DELAY_NEW_VALUE_WEIGHT			4
-#define ENA_INTR_MODER_LEVEL_STRIDE			2
-#define ENA_INTR_BYTE_COUNT_NOT_SUPPORTED		0xFFFFFF
 
 #define ENA_HW_HINTS_NO_TIMEOUT				0xFFFF
 
 #define ENA_FEATURE_MAX_QUEUE_EXT_VER	1
 
-enum ena_intr_moder_level {
-	ENA_INTR_MODER_LOWEST = 0,
-	ENA_INTR_MODER_LOW,
-	ENA_INTR_MODER_MID,
-	ENA_INTR_MODER_HIGH,
-	ENA_INTR_MODER_HIGHEST,
-	ENA_INTR_MAX_NUM_OF_LEVELS,
-};
-
 struct ena_llq_configurations {
 	enum ena_admin_llq_header_location llq_header_location;
 	enum ena_admin_llq_ring_entry_size llq_ring_entry_size;
@@ -120,12 +87,6 @@ struct ena_llq_configurations {
 	u16 llq_ring_entry_size_value;
 };
 
-struct ena_intr_moder_entry {
-	unsigned int intr_moder_interval;
-	unsigned int pkts_per_interval;
-	unsigned int bytes_per_interval;
-};
-
 enum queue_direction {
 	ENA_COM_IO_QUEUE_DIRECTION_TX,
 	ENA_COM_IO_QUEUE_DIRECTION_RX
@@ -920,11 +881,6 @@ int ena_com_execute_admin_command(struct ena_com_admin_queue *admin_queue,
  */
 int ena_com_init_interrupt_moderation(struct ena_com_dev *ena_dev);
 
-/* ena_com_destroy_interrupt_moderation - Destroy interrupt moderation resources
- * @ena_dev: ENA communication layer struct
- */
-void ena_com_destroy_interrupt_moderation(struct ena_com_dev *ena_dev);
-
 /* ena_com_interrupt_moderation_supported - Return if interrupt moderation
  * capability is supported by the device.
  *
@@ -932,12 +888,6 @@ void ena_com_destroy_interrupt_moderation(struct ena_com_dev *ena_dev);
  */
 bool ena_com_interrupt_moderation_supported(struct ena_com_dev *ena_dev);
 
-/* ena_com_config_default_interrupt_moderation_table - Restore the interrupt
- * moderation table back to the default parameters.
- * @ena_dev: ENA communication layer struct
- */
-void ena_com_config_default_interrupt_moderation_table(struct ena_com_dev *ena_dev);
-
 /* ena_com_update_nonadaptive_moderation_interval_tx - Update the
  * non-adaptive interval in Tx direction.
  * @ena_dev: ENA communication layer struct
@@ -974,29 +924,6 @@ unsigned int ena_com_get_nonadaptive_moderation_interval_tx(struct ena_com_dev *
  */
 unsigned int ena_com_get_nonadaptive_moderation_interval_rx(struct ena_com_dev *ena_dev);
 
-/* ena_com_init_intr_moderation_entry - Update a single entry in the interrupt
- * moderation table.
- * @ena_dev: ENA communication layer struct
- * @level: Interrupt moderation table level
- * @entry: Entry value
- *
- * Update a single entry in the interrupt moderation table.
- */
-void ena_com_init_intr_moderation_entry(struct ena_com_dev *ena_dev,
-					enum ena_intr_moder_level level,
-					struct ena_intr_moder_entry *entry);
-
-/* ena_com_get_intr_moderation_entry - Init ena_intr_moder_entry.
- * @ena_dev: ENA communication layer struct
- * @level: Interrupt moderation table level
- * @entry: Entry to fill.
- *
- * Initialize the entry according to the adaptive interrupt moderation table.
- */
-void ena_com_get_intr_moderation_entry(struct ena_com_dev *ena_dev,
-				       enum ena_intr_moder_level level,
-				       struct ena_intr_moder_entry *entry);
-
 /* ena_com_config_dev_mode - Configure the placement policy of the device.
  * @ena_dev: ENA communication layer struct
  * @llq_features: LLQ feature descriptor, retrieve via
@@ -1022,75 +949,6 @@ static inline void ena_com_disable_adaptive_moderation(struct ena_com_dev *ena_d
 	ena_dev->adaptive_coalescing = false;
 }
 
-/* ena_com_calculate_interrupt_delay - Calculate new interrupt delay
- * @ena_dev: ENA communication layer struct
- * @pkts: Number of packets since the last update
- * @bytes: Number of bytes received since the last update.
- * @smoothed_interval: Returned interval
- * @moder_tbl_idx: Current table level as input update new level as return
- * value.
- */
-static inline void ena_com_calculate_interrupt_delay(struct ena_com_dev *ena_dev,
-						     unsigned int pkts,
-						     unsigned int bytes,
-						     unsigned int *smoothed_interval,
-						     unsigned int *moder_tbl_idx)
-{
-	enum ena_intr_moder_level curr_moder_idx, new_moder_idx;
-	struct ena_intr_moder_entry *curr_moder_entry;
-	struct ena_intr_moder_entry *pred_moder_entry;
-	struct ena_intr_moder_entry *new_moder_entry;
-	struct ena_intr_moder_entry *intr_moder_tbl = ena_dev->intr_moder_tbl;
-	unsigned int interval;
-
-	/* We apply adaptive moderation on Rx path only.
-	 * Tx uses static interrupt moderation.
-	 */
-	if (!pkts || !bytes)
-		/* Tx interrupt, or spurious interrupt,
-		 * in both cases we just use same delay values
-		 */
-		return;
-
-	curr_moder_idx = (enum ena_intr_moder_level)(*moder_tbl_idx);
-	if (unlikely(curr_moder_idx >= ENA_INTR_MAX_NUM_OF_LEVELS)) {
-		pr_err("Wrong moderation index %u\n", curr_moder_idx);
-		return;
-	}
-
-	curr_moder_entry = &intr_moder_tbl[curr_moder_idx];
-	new_moder_idx = curr_moder_idx;
-
-	if (curr_moder_idx == ENA_INTR_MODER_LOWEST) {
-		if ((pkts > curr_moder_entry->pkts_per_interval) ||
-		    (bytes > curr_moder_entry->bytes_per_interval))
-			new_moder_idx =
-				(enum ena_intr_moder_level)(curr_moder_idx + ENA_INTR_MODER_LEVEL_STRIDE);
-	} else {
-		pred_moder_entry = &intr_moder_tbl[curr_moder_idx - ENA_INTR_MODER_LEVEL_STRIDE];
-
-		if ((pkts <= pred_moder_entry->pkts_per_interval) ||
-		    (bytes <= pred_moder_entry->bytes_per_interval))
-			new_moder_idx =
-				(enum ena_intr_moder_level)(curr_moder_idx - ENA_INTR_MODER_LEVEL_STRIDE);
-		else if ((pkts > curr_moder_entry->pkts_per_interval) ||
-			 (bytes > curr_moder_entry->bytes_per_interval)) {
-			if (curr_moder_idx != ENA_INTR_MODER_HIGHEST)
-				new_moder_idx =
-					(enum ena_intr_moder_level)(curr_moder_idx + ENA_INTR_MODER_LEVEL_STRIDE);
-		}
-	}
-	new_moder_entry = &intr_moder_tbl[new_moder_idx];
-
-	interval = new_moder_entry->intr_moder_interval;
-	*smoothed_interval = (
-		(interval * ENA_INTR_DELAY_NEW_VALUE_WEIGHT +
-		ENA_INTR_DELAY_OLD_VALUE_WEIGHT * (*smoothed_interval)) + 5) /
-		10;
-
-	*moder_tbl_idx = new_moder_idx;
-}
-
 /* ena_com_update_intr_reg - Prepare interrupt register
  * @intr_reg: interrupt register to update.
  * @rx_delay_interval: Rx interval in usecs

From 7b8a28787e2ba671eaeb073e3b62fb4786338a09 Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:34 +0300
Subject: [PATCH 09/11] net: ena: fix update of interrupt moderation register

Current implementation always updates the interrupt register with
the smoothed_interval of the rx_ring. However this should be
done only in case of adaptive interrupt moderation. If non-adaptive
interrupt moderation is used, the non-adaptive interrupt moderation
interval should be used. This commit fixes that.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_netdev.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index 8b9f8b90e525..54539e57aa73 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -1187,12 +1187,15 @@ static void ena_unmask_interrupt(struct ena_ring *tx_ring,
 					struct ena_ring *rx_ring)
 {
 	struct ena_eth_io_intr_reg intr_reg;
+	u32 rx_interval = ena_com_get_adaptive_moderation_enabled(rx_ring->ena_dev) ?
+		rx_ring->smoothed_interval :
+		ena_com_get_nonadaptive_moderation_interval_rx(rx_ring->ena_dev);
 
 	/* Update intr register: rx intr delay,
 	 * tx intr delay and interrupt unmask
 	 */
 	ena_com_update_intr_reg(&intr_reg,
-				rx_ring->smoothed_interval,
+				rx_interval,
 				tx_ring->smoothed_interval,
 				true);
 

From 0eda847953d8dfb4b713ea62420f66157e230e13 Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:35 +0300
Subject: [PATCH 10/11] net: ena: fix retrieval of nonadaptive interrupt
 moderation intervals

Nonadaptive interrupt moderation intervals are assigned the value set
by the user in ethtool -C divided by ena_dev->intr_delay_resolution.

Therefore when the user tries to get the nonadaptive interrupt moderation
intervals with ethtool -c the code needs to multiply the saved value
by ena_dev->intr_delay_resolution.

The current code erroneously divides instead of multiplying in ethtool -c.
This patch fixes this.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_ethtool.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_ethtool.c b/drivers/net/ethernet/amazon/ena/ena_ethtool.c
index 0f90e2296630..16553d92fad2 100644
--- a/drivers/net/ethernet/amazon/ena/ena_ethtool.c
+++ b/drivers/net/ethernet/amazon/ena/ena_ethtool.c
@@ -310,14 +310,15 @@ static int ena_get_coalesce(struct net_device *net_dev,
 		/* the devie doesn't support interrupt moderation */
 		return -EOPNOTSUPP;
 	}
+
 	coalesce->tx_coalesce_usecs =
-		ena_com_get_nonadaptive_moderation_interval_tx(ena_dev) /
+		ena_com_get_nonadaptive_moderation_interval_tx(ena_dev) *
 			ena_dev->intr_delay_resolution;
 
 	if (!ena_com_get_adaptive_moderation_enabled(ena_dev))
 		coalesce->rx_coalesce_usecs =
 			ena_com_get_nonadaptive_moderation_interval_rx(ena_dev)
-			/ ena_dev->intr_delay_resolution;
+			* ena_dev->intr_delay_resolution;
 
 	coalesce->use_adaptive_rx_coalesce =
 		ena_com_get_adaptive_moderation_enabled(ena_dev);

From 79226cea4a5ebbd84a4eee1762526f664c7beb62 Mon Sep 17 00:00:00 2001
From: Arthur Kiyanovski <akiyano@amazon.com>
Date: Mon, 16 Sep 2019 14:31:36 +0300
Subject: [PATCH 11/11] net: ena: fix incorrect update of intr_delay_resolution

ena_dev->intr_moder_rx/tx_interval save the intervals received from the
user after dividing them by ena_dev->intr_delay_resolution. Therefore
when intr_delay_resolution changes, the code needs to first mutiply
intr_moder_rx/tx_interval by the previous intr_delay_resolution to get
the value originally given by the user, and only then divide it by the
new intr_delay_resolution.

Current code does not first multiply intr_moder_rx/tx_interval by the old
intr_delay_resolution. This commit fixes it.

Also initialize ena_dev->intr_delay_resolution to be 1.

Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/ethernet/amazon/ena/ena_com.c    | 21 ++++++++++++++++----
 drivers/net/ethernet/amazon/ena/ena_com.h    |  1 +
 drivers/net/ethernet/amazon/ena/ena_netdev.c |  1 +
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/amazon/ena/ena_com.c b/drivers/net/ethernet/amazon/ena/ena_com.c
index 621b747f062b..ea62604fdf8c 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.c
+++ b/drivers/net/ethernet/amazon/ena/ena_com.c
@@ -1281,17 +1281,30 @@ static int ena_com_ind_tbl_convert_from_device(struct ena_com_dev *ena_dev)
 static void ena_com_update_intr_delay_resolution(struct ena_com_dev *ena_dev,
 						 u16 intr_delay_resolution)
 {
+	/* Initial value of intr_delay_resolution might be 0 */
+	u16 prev_intr_delay_resolution =
+		ena_dev->intr_delay_resolution ?
+		ena_dev->intr_delay_resolution :
+		ENA_DEFAULT_INTR_DELAY_RESOLUTION;
+
 	if (!intr_delay_resolution) {
 		pr_err("Illegal intr_delay_resolution provided. Going to use default 1 usec resolution\n");
-		intr_delay_resolution = 1;
+		intr_delay_resolution = ENA_DEFAULT_INTR_DELAY_RESOLUTION;
 	}
-	ena_dev->intr_delay_resolution = intr_delay_resolution;
 
 	/* update Rx */
-	ena_dev->intr_moder_rx_interval /= intr_delay_resolution;
+	ena_dev->intr_moder_rx_interval =
+		ena_dev->intr_moder_rx_interval *
+		prev_intr_delay_resolution /
+		intr_delay_resolution;
 
 	/* update Tx */
-	ena_dev->intr_moder_tx_interval /= intr_delay_resolution;
+	ena_dev->intr_moder_tx_interval =
+		ena_dev->intr_moder_tx_interval *
+		prev_intr_delay_resolution /
+		intr_delay_resolution;
+
+	ena_dev->intr_delay_resolution = intr_delay_resolution;
 }
 
 /*****************************************************************************/
diff --git a/drivers/net/ethernet/amazon/ena/ena_com.h b/drivers/net/ethernet/amazon/ena/ena_com.h
index ddc2a8c50333..7c941eba0bc9 100644
--- a/drivers/net/ethernet/amazon/ena/ena_com.h
+++ b/drivers/net/ethernet/amazon/ena/ena_com.h
@@ -74,6 +74,7 @@
 
 #define ENA_INTR_INITIAL_TX_INTERVAL_USECS		196
 #define ENA_INTR_INITIAL_RX_INTERVAL_USECS		0
+#define ENA_DEFAULT_INTR_DELAY_RESOLUTION		1
 
 #define ENA_HW_HINTS_NO_TIMEOUT				0xFFFF
 
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c
index 54539e57aa73..e4bf7a4af87a 100644
--- a/drivers/net/ethernet/amazon/ena/ena_netdev.c
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c
@@ -3500,6 +3500,7 @@ static int ena_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	*/
 	ena_dev->intr_moder_tx_interval = ENA_INTR_INITIAL_TX_INTERVAL_USECS;
 	ena_dev->intr_moder_rx_interval = ENA_INTR_INITIAL_RX_INTERVAL_USECS;
+	ena_dev->intr_delay_resolution = ENA_DEFAULT_INTR_DELAY_RESOLUTION;
 	io_queue_num = ena_calc_io_queue_num(pdev, ena_dev, &get_feat_ctx);
 	rc = ena_calc_queue_size(&calc_queue_ctx);
 	if (rc || io_queue_num <= 0) {