net: hns3: change the time interval of int_gl calculating

Since we change the update rate of int_gl from every interrupt to every
one hundred interrupts, the old way to get time interval by int_gl value
is not accurate. This patch calculates the time interval using the jiffies
value.

Signed-off-by: Fuyun Liang <liangfuyun1@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 30 insertions, 17 deletions

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index e7cf7b4b40d3..0b4a676999ca 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -2406,15 +2406,15 @@ out:
 
 static bool hns3_get_new_int_gl(struct hns3_enet_ring_group *ring_group)
 {
-#define HNS3_RX_ULTRA_PACKET_RATE 40000
+        struct hns3_enet_tqp_vector *tqp_vector =
+                                        ring_group->ring->tqp_vector;
         enum hns3_flow_level_range new_flow_level;
-        struct hns3_enet_tqp_vector *tqp_vector;
-        int packets_per_secs;
-        int bytes_per_usecs;
+        int packets_per_msecs;
+        int bytes_per_msecs;
+        u32 time_passed_ms;
         u16 new_int_gl;
-        int usecs;
 
-        if (!ring_group->coal.int_gl)
+        if (!ring_group->coal.int_gl || !tqp_vector->last_jiffies)
                 return false;
 
         if (ring_group->total_packets == 0) {
@@ -2431,33 +2431,44 @@ static bool hns3_get_new_int_gl(struct hns3_enet_ring_group *ring_group)
          */
         new_flow_level = ring_group->coal.flow_level;
         new_int_gl = ring_group->coal.int_gl;
-        tqp_vector = ring_group->ring->tqp_vector;
-        usecs = (ring_group->coal.int_gl << 1);
-        bytes_per_usecs = ring_group->total_bytes / usecs;
-        /* 1000000 microseconds */
-        packets_per_secs = ring_group->total_packets * 1000000 / usecs;
+        time_passed_ms =
+                jiffies_to_msecs(jiffies - tqp_vector->last_jiffies);
+
+        if (!time_passed_ms)
+                return false;
+
+        do_div(ring_group->total_packets, time_passed_ms);
+        packets_per_msecs = ring_group->total_packets;
+
+        do_div(ring_group->total_bytes, time_passed_ms);
+        bytes_per_msecs = ring_group->total_bytes;
+
+#define HNS3_RX_LOW_BYTE_RATE 10000
+#define HNS3_RX_MID_BYTE_RATE 20000
 
         switch (new_flow_level) {
         case HNS3_FLOW_LOW:
-                if (bytes_per_usecs > 10)
+                if (bytes_per_msecs > HNS3_RX_LOW_BYTE_RATE)
                         new_flow_level = HNS3_FLOW_MID;
                 break;
         case HNS3_FLOW_MID:
-                if (bytes_per_usecs > 20)
+                if (bytes_per_msecs > HNS3_RX_MID_BYTE_RATE)
                         new_flow_level = HNS3_FLOW_HIGH;
-                else if (bytes_per_usecs <= 10)
+                else if (bytes_per_msecs <= HNS3_RX_LOW_BYTE_RATE)
                         new_flow_level = HNS3_FLOW_LOW;
                 break;
         case HNS3_FLOW_HIGH:
         case HNS3_FLOW_ULTRA:
         default:
-                if (bytes_per_usecs <= 20)
+                if (bytes_per_msecs <= HNS3_RX_MID_BYTE_RATE)
                         new_flow_level = HNS3_FLOW_MID;
                 break;
         }
 
-        if ((packets_per_secs > HNS3_RX_ULTRA_PACKET_RATE) &&
-            (&tqp_vector->rx_group == ring_group))
+#define HNS3_RX_ULTRA_PACKET_RATE 40
+
+        if (packets_per_msecs > HNS3_RX_ULTRA_PACKET_RATE &&
+            &tqp_vector->rx_group == ring_group)
                 new_flow_level = HNS3_FLOW_ULTRA;
 
         switch (new_flow_level) {
@@ -2512,6 +2523,7 @@ static void hns3_update_new_int_gl(struct hns3_enet_tqp_vector *tqp_vector)
                                                        tx_group->coal.int_gl);
         }
 
+        tqp_vector->last_jiffies = jiffies;
         tqp_vector->int_adapt_down = HNS3_INT_ADAPT_DOWN_START;
 }
 
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
index 2fe870b580b1..39daa01f08d5 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.h
@@ -499,6 +499,7 @@ struct hns3_enet_tqp_vector {
 
         /* when 0 should adjust interrupt coalesce parameter */
         u8 int_adapt_down;
+        unsigned long last_jiffies;
 } ____cacheline_internodealigned_in_smp;
 
 enum hns3_udp_tnl_type {