diff options
| -rw-r--r-- | drivers/net/ethernet/marvell/mvneta.c | 184 |
1 files changed, 101 insertions, 83 deletions
diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index 662c2ee268c7..b0ae69f84493 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -370,6 +370,11 @@ struct mvneta_port { struct net_device *dev; struct notifier_block cpu_notifier; int rxq_def; + /* Protect the access to the percpu interrupt registers, + * ensuring that the configuration remains coherent. + */ + spinlock_t lock; + bool is_stopped; /* Core clock */ struct clk *clk; @@ -1038,6 +1043,43 @@ static void mvneta_set_autoneg(struct mvneta_port *pp, int enable) } } +static void mvneta_percpu_unmask_interrupt(void *arg) +{ + struct mvneta_port *pp = arg; + + /* All the queue are unmasked, but actually only the ones + * mapped to this CPU will be unmasked + */ + mvreg_write(pp, MVNETA_INTR_NEW_MASK, + MVNETA_RX_INTR_MASK_ALL | + MVNETA_TX_INTR_MASK_ALL | + MVNETA_MISCINTR_INTR_MASK); +} + +static void mvneta_percpu_mask_interrupt(void *arg) +{ + struct mvneta_port *pp = arg; + + /* All the queue are masked, but actually only the ones + * mapped to this CPU will be masked + */ + mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0); + mvreg_write(pp, MVNETA_INTR_OLD_MASK, 0); + mvreg_write(pp, MVNETA_INTR_MISC_MASK, 0); +} + +static void mvneta_percpu_clear_intr_cause(void *arg) +{ + struct mvneta_port *pp = arg; + + /* All the queue are cleared, but actually only the ones + * mapped to this CPU will be cleared + */ + mvreg_write(pp, MVNETA_INTR_NEW_CAUSE, 0); + mvreg_write(pp, MVNETA_INTR_MISC_CAUSE, 0); + mvreg_write(pp, MVNETA_INTR_OLD_CAUSE, 0); +} + /* This method sets defaults to the NETA port: * Clears interrupt Cause and Mask registers. * Clears all MAC tables. @@ -1055,14 +1097,10 @@ static void mvneta_defaults_set(struct mvneta_port *pp) int max_cpu = num_present_cpus(); /* Clear all Cause registers */ - mvreg_write(pp, MVNETA_INTR_NEW_CAUSE, 0); - mvreg_write(pp, MVNETA_INTR_OLD_CAUSE, 0); - mvreg_write(pp, MVNETA_INTR_MISC_CAUSE, 0); + on_each_cpu(mvneta_percpu_clear_intr_cause, pp, true); /* Mask all interrupts */ - mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0); - mvreg_write(pp, MVNETA_INTR_OLD_MASK, 0); - mvreg_write(pp, MVNETA_INTR_MISC_MASK, 0); + on_each_cpu(mvneta_percpu_mask_interrupt, pp, true); mvreg_write(pp, MVNETA_INTR_ENABLE, 0); /* Enable MBUS Retry bit16 */ @@ -2528,34 +2566,9 @@ static int mvneta_setup_txqs(struct mvneta_port *pp) return 0; } -static void mvneta_percpu_unmask_interrupt(void *arg) -{ - struct mvneta_port *pp = arg; - - /* All the queue are unmasked, but actually only the ones - * maped to this CPU will be unmasked - */ - mvreg_write(pp, MVNETA_INTR_NEW_MASK, - MVNETA_RX_INTR_MASK_ALL | - MVNETA_TX_INTR_MASK_ALL | - MVNETA_MISCINTR_INTR_MASK); -} - -static void mvneta_percpu_mask_interrupt(void *arg) -{ - struct mvneta_port *pp = arg; - - /* All the queue are masked, but actually only the ones - * maped to this CPU will be masked - */ - mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0); - mvreg_write(pp, MVNETA_INTR_OLD_MASK, 0); - mvreg_write(pp, MVNETA_INTR_MISC_MASK, 0); -} - static void mvneta_start_dev(struct mvneta_port *pp) { - unsigned int cpu; + int cpu; mvneta_max_rx_size_set(pp, pp->pkt_size); mvneta_txq_max_tx_size_set(pp, pp->pkt_size); @@ -2564,16 +2577,15 @@ static void mvneta_start_dev(struct mvneta_port *pp) mvneta_port_enable(pp); /* Enable polling on the port */ - for_each_present_cpu(cpu) { + for_each_online_cpu(cpu) { struct mvneta_pcpu_port *port = per_cpu_ptr(pp->ports, cpu); napi_enable(&port->napi); } /* Unmask interrupts. It has to be done from each CPU */ - for_each_online_cpu(cpu) - smp_call_function_single(cpu, mvneta_percpu_unmask_interrupt, - pp, true); + on_each_cpu(mvneta_percpu_unmask_interrupt, pp, true); + mvreg_write(pp, MVNETA_INTR_MISC_MASK, MVNETA_CAUSE_PHY_STATUS_CHANGE | MVNETA_CAUSE_LINK_CHANGE | @@ -2589,7 +2601,7 @@ static void mvneta_stop_dev(struct mvneta_port *pp) phy_stop(pp->phy_dev); - for_each_present_cpu(cpu) { + for_each_online_cpu(cpu) { struct mvneta_pcpu_port *port = per_cpu_ptr(pp->ports, cpu); napi_disable(&port->napi); @@ -2604,13 +2616,10 @@ static void mvneta_stop_dev(struct mvneta_port *pp) mvneta_port_disable(pp); /* Clear all ethernet port interrupts */ - mvreg_write(pp, MVNETA_INTR_MISC_CAUSE, 0); - mvreg_write(pp, MVNETA_INTR_OLD_CAUSE, 0); + on_each_cpu(mvneta_percpu_clear_intr_cause, pp, true); /* Mask all ethernet port interrupts */ - mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0); - mvreg_write(pp, MVNETA_INTR_OLD_MASK, 0); - mvreg_write(pp, MVNETA_INTR_MISC_MASK, 0); + on_each_cpu(mvneta_percpu_mask_interrupt, pp, true); mvneta_tx_reset(pp); mvneta_rx_reset(pp); @@ -2847,11 +2856,20 @@ static void mvneta_percpu_disable(void *arg) disable_percpu_irq(pp->dev->irq); } +/* Electing a CPU must be done in an atomic way: it should be done + * after or before the removal/insertion of a CPU and this function is + * not reentrant. + */ static void mvneta_percpu_elect(struct mvneta_port *pp) { - int online_cpu_idx, max_cpu, cpu, i = 0; + int elected_cpu = 0, max_cpu, cpu, i = 0; + + /* Use the cpu associated to the rxq when it is online, in all + * the other cases, use the cpu 0 which can't be offline. + */ + if (cpu_online(pp->rxq_def)) + elected_cpu = pp->rxq_def; - online_cpu_idx = pp->rxq_def % num_online_cpus(); max_cpu = num_present_cpus(); for_each_online_cpu(cpu) { @@ -2862,7 +2880,7 @@ static void mvneta_percpu_elect(struct mvneta_port *pp) if ((rxq % max_cpu) == cpu) rxq_map |= MVNETA_CPU_RXQ_ACCESS(rxq); - if (i == online_cpu_idx) + if (cpu == elected_cpu) /* Map the default receive queue queue to the * elected CPU */ @@ -2873,7 +2891,7 @@ static void mvneta_percpu_elect(struct mvneta_port *pp) * the CPU bound to the default RX queue */ if (txq_number == 1) - txq_map = (i == online_cpu_idx) ? + txq_map = (cpu == elected_cpu) ? MVNETA_CPU_TXQ_ACCESS(1) : 0; else txq_map = mvreg_read(pp, MVNETA_CPU_MAP(cpu)) & @@ -2902,6 +2920,14 @@ static int mvneta_percpu_notifier(struct notifier_block *nfb, switch (action) { case CPU_ONLINE: case CPU_ONLINE_FROZEN: + spin_lock(&pp->lock); + /* Configuring the driver for a new CPU while the + * driver is stopping is racy, so just avoid it. + */ + if (pp->is_stopped) { + spin_unlock(&pp->lock); + break; + } netif_tx_stop_all_queues(pp->dev); /* We have to synchronise on tha napi of each CPU @@ -2917,9 +2943,7 @@ static int mvneta_percpu_notifier(struct notifier_block *nfb, } /* Mask all ethernet port interrupts */ - mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0); - mvreg_write(pp, MVNETA_INTR_OLD_MASK, 0); - mvreg_write(pp, MVNETA_INTR_MISC_MASK, 0); + on_each_cpu(mvneta_percpu_mask_interrupt, pp, true); napi_enable(&port->napi); @@ -2934,27 +2958,25 @@ static int mvneta_percpu_notifier(struct notifier_block *nfb, */ mvneta_percpu_elect(pp); - /* Unmask all ethernet port interrupts, as this - * notifier is called for each CPU then the CPU to - * Queue mapping is applied - */ - mvreg_write(pp, MVNETA_INTR_NEW_MASK, - MVNETA_RX_INTR_MASK(rxq_number) | - MVNETA_TX_INTR_MASK(txq_number) | - MVNETA_MISCINTR_INTR_MASK); + /* Unmask all ethernet port interrupts */ + on_each_cpu(mvneta_percpu_unmask_interrupt, pp, true); mvreg_write(pp, MVNETA_INTR_MISC_MASK, MVNETA_CAUSE_PHY_STATUS_CHANGE | MVNETA_CAUSE_LINK_CHANGE | MVNETA_CAUSE_PSC_SYNC_CHANGE); netif_tx_start_all_queues(pp->dev); + spin_unlock(&pp->lock); break; case CPU_DOWN_PREPARE: case CPU_DOWN_PREPARE_FROZEN: netif_tx_stop_all_queues(pp->dev); + /* Thanks to this lock we are sure that any pending + * cpu election is done + */ + spin_lock(&pp->lock); /* Mask all ethernet port interrupts */ - mvreg_write(pp, MVNETA_INTR_NEW_MASK, 0); - mvreg_write(pp, MVNETA_INTR_OLD_MASK, 0); - mvreg_write(pp, MVNETA_INTR_MISC_MASK, 0); + on_each_cpu(mvneta_percpu_mask_interrupt, pp, true); + spin_unlock(&pp->lock); napi_synchronize(&port->napi); napi_disable(&port->napi); @@ -2968,12 +2990,11 @@ static int mvneta_percpu_notifier(struct notifier_block *nfb, case CPU_DEAD: case CPU_DEAD_FROZEN: /* Check if a new CPU must be elected now this on is down */ + spin_lock(&pp->lock); mvneta_percpu_elect(pp); + spin_unlock(&pp->lock); /* Unmask all ethernet port interrupts */ - mvreg_write(pp, MVNETA_INTR_NEW_MASK, - MVNETA_RX_INTR_MASK(rxq_number) | - MVNETA_TX_INTR_MASK(txq_number) | - MVNETA_MISCINTR_INTR_MASK); + on_each_cpu(mvneta_percpu_unmask_interrupt, pp, true); mvreg_write(pp, MVNETA_INTR_MISC_MASK, MVNETA_CAUSE_PHY_STATUS_CHANGE | MVNETA_CAUSE_LINK_CHANGE | @@ -2988,7 +3009,7 @@ static int mvneta_percpu_notifier(struct notifier_block *nfb, static int mvneta_open(struct net_device *dev) { struct mvneta_port *pp = netdev_priv(dev); - int ret, cpu; + int ret; pp->pkt_size = MVNETA_RX_PKT_SIZE(pp->dev->mtu); pp->frag_size = SKB_DATA_ALIGN(MVNETA_RX_BUF_SIZE(pp->pkt_size)) + @@ -3010,22 +3031,12 @@ static int mvneta_open(struct net_device *dev) goto err_cleanup_txqs; } - /* Even though the documentation says that request_percpu_irq - * doesn't enable the interrupts automatically, it actually - * does so on the local CPU. - * - * Make sure it's disabled. - */ - mvneta_percpu_disable(pp); - /* Enable per-CPU interrupt on all the CPU to handle our RX * queue interrupts */ - for_each_online_cpu(cpu) - smp_call_function_single(cpu, mvneta_percpu_enable, - pp, true); - + on_each_cpu(mvneta_percpu_enable, pp, true); + pp->is_stopped = false; /* Register a CPU notifier to handle the case where our CPU * might be taken offline. */ @@ -3057,13 +3068,20 @@ err_cleanup_rxqs: static int mvneta_stop(struct net_device *dev) { struct mvneta_port *pp = netdev_priv(dev); - int cpu; + /* Inform that we are stopping so we don't want to setup the + * driver for new CPUs in the notifiers + */ + spin_lock(&pp->lock); + pp->is_stopped = true; mvneta_stop_dev(pp); mvneta_mdio_remove(pp); unregister_cpu_notifier(&pp->cpu_notifier); - for_each_present_cpu(cpu) - smp_call_function_single(cpu, mvneta_percpu_disable, pp, true); + /* Now that the notifier are unregistered, we can release le + * lock + */ + spin_unlock(&pp->lock); + on_each_cpu(mvneta_percpu_disable, pp, true); free_percpu_irq(dev->irq, pp->ports); mvneta_cleanup_rxqs(pp); mvneta_cleanup_txqs(pp); @@ -3312,9 +3330,7 @@ static int mvneta_config_rss(struct mvneta_port *pp) netif_tx_stop_all_queues(pp->dev); - for_each_online_cpu(cpu) - smp_call_function_single(cpu, mvneta_percpu_mask_interrupt, - pp, true); + on_each_cpu(mvneta_percpu_mask_interrupt, pp, true); /* We have to synchronise on the napi of each CPU */ for_each_online_cpu(cpu) { @@ -3335,7 +3351,9 @@ static int mvneta_config_rss(struct mvneta_port *pp) mvreg_write(pp, MVNETA_PORT_CONFIG, val); /* Update the elected CPU matching the new rxq_def */ + spin_lock(&pp->lock); mvneta_percpu_elect(pp); + spin_unlock(&pp->lock); /* We have to synchronise on the napi of each CPU */ for_each_online_cpu(cpu) { |