net/mvpp2: Replace tasklet with softirq hrtimer

The tx_done_tasklet tasklet is used in invoke the hrtimer
(mvpp2_hr_timer_cb) in softirq context. This can be also achieved without
the tasklet but with HRTIMER_MODE_SOFT as hrtimer mode.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
index 4d9564b..ee3bab5 100644 (file)
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
@@ -829,9 +829,8 @@ struct mvpp2_pcpu_stats {
 /* Per-CPU port control */
 struct mvpp2_port_pcpu {
        struct hrtimer tx_done_timer;
+       struct net_device *dev;
        bool timer_scheduled;
-       /* Tasklet for egress finalization */
-       struct tasklet_struct tx_done_tasklet;
 };
 
 struct mvpp2_queue_vector {

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index 74fd9e1..12e799e 100644 (file)
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -2651,31 +2651,21 @@ handled:
        return IRQ_HANDLED;
 }
 
-static void mvpp2_timer_set(struct mvpp2_port_pcpu *port_pcpu)
-{
-       ktime_t interval;
-
-       if (!port_pcpu->timer_scheduled) {
-               port_pcpu->timer_scheduled = true;
-               interval = MVPP2_TXDONE_HRTIMER_PERIOD_NS;
-               hrtimer_start(&port_pcpu->tx_done_timer, interval,
-                             HRTIMER_MODE_REL_PINNED);
-       }
-}
-
-static void mvpp2_tx_proc_cb(unsigned long data)
+static enum hrtimer_restart mvpp2_hr_timer_cb(struct hrtimer *timer)
 {
-       struct net_device *dev = (struct net_device *)data;
-       struct mvpp2_port *port = netdev_priv(dev);
+       struct net_device *dev;
+       struct mvpp2_port *port;
        struct mvpp2_port_pcpu *port_pcpu;
        unsigned int tx_todo, cause;
 
-       port_pcpu = per_cpu_ptr(port->pcpu,
-                               mvpp2_cpu_to_thread(port->priv, smp_processor_id()));
+       port_pcpu = container_of(timer, struct mvpp2_port_pcpu, tx_done_timer);
+       dev = port_pcpu->dev;
 
        if (!netif_running(dev))
-               return;
+               return HRTIMER_NORESTART;
+
        port_pcpu->timer_scheduled = false;
+       port = netdev_priv(dev);
 
        /* Process all the Tx queues */
        cause = (1 << port->ntxqs) - 1;
@@ -2683,18 +2673,13 @@ static void mvpp2_tx_proc_cb(unsigned long data)
                                mvpp2_cpu_to_thread(port->priv, smp_processor_id()));
 
        /* Set the timer in case not all the packets were processed */
-       if (tx_todo)
-               mvpp2_timer_set(port_pcpu);
-}
-
-static enum hrtimer_restart mvpp2_hr_timer_cb(struct hrtimer *timer)
-{
-       struct mvpp2_port_pcpu *port_pcpu = container_of(timer,
-                                                        struct mvpp2_port_pcpu,
-                                                        tx_done_timer);
-
-       tasklet_schedule(&port_pcpu->tx_done_tasklet);
+       if (tx_todo && !port_pcpu->timer_scheduled) {
+               port_pcpu->timer_scheduled = true;
+               hrtimer_forward_now(&port_pcpu->tx_done_timer,
+                                   MVPP2_TXDONE_HRTIMER_PERIOD_NS);
 
+               return HRTIMER_RESTART;
+       }
        return HRTIMER_NORESTART;
 }
 
@@ -3182,7 +3167,12 @@ out:
            txq_pcpu->count > 0) {
                struct mvpp2_port_pcpu *port_pcpu = per_cpu_ptr(port->pcpu, thread);
 
-               mvpp2_timer_set(port_pcpu);
+               if (!port_pcpu->timer_scheduled) {
+                       port_pcpu->timer_scheduled = true;
+                       hrtimer_start(&port_pcpu->tx_done_timer,
+                                     MVPP2_TXDONE_HRTIMER_PERIOD_NS,
+                                     HRTIMER_MODE_REL_PINNED_SOFT);
+               }
        }
 
        if (test_bit(thread, &port->priv->lock_map))
@@ -3619,7 +3609,6 @@ static int mvpp2_stop(struct net_device *dev)
 
                        hrtimer_cancel(&port_pcpu->tx_done_timer);
                        port_pcpu->timer_scheduled = false;
-                       tasklet_kill(&port_pcpu->tx_done_tasklet);
                }
        }
        mvpp2_cleanup_rxqs(port);
@@ -5183,13 +5172,10 @@ static int mvpp2_port_probe(struct platform_device *pdev,
                        port_pcpu = per_cpu_ptr(port->pcpu, thread);
 
                        hrtimer_init(&port_pcpu->tx_done_timer, CLOCK_MONOTONIC,
-                                    HRTIMER_MODE_REL_PINNED);
+                                    HRTIMER_MODE_REL_PINNED_SOFT);
                        port_pcpu->tx_done_timer.function = mvpp2_hr_timer_cb;
                        port_pcpu->timer_scheduled = false;
-
-                       tasklet_init(&port_pcpu->tx_done_tasklet,
-                                    mvpp2_tx_proc_cb,
-                                    (unsigned long)dev);
+                       port_pcpu->dev = dev;
                }
        }