[ANNOUNCE] v5.11-rc5-rt3

@@ -2054,7 +2054,7 @@ static int eni_send(struct atm_vcc *vcc,struct sk_buff *skb)
 	}
 	submitted++;
 	ATM_SKB(skb)->vcc = vcc;
-	tasklet_disable(&ENI_DEV(vcc->dev)->task);
+	tasklet_disable_in_atomic(&ENI_DEV(vcc->dev)->task);
 	res = do_tx(skb);
 	tasklet_enable(&ENI_DEV(vcc->dev)->task);
 	if (res == enq_ok) return 0;

@@ -2545,7 +2545,7 @@ static int ohci_cancel_packet(struct fw_card *card, struct fw_packet *packet)
 	struct driver_data *driver_data = packet->driver_data;
 	int ret = -ENOENT;
 
-	tasklet_disable(&ctx->tasklet);
+	tasklet_disable_in_atomic(&ctx->tasklet);
 
 	if (packet->ack != 0)
 		goto out;

@@ -3465,7 +3465,7 @@ static int ohci_flush_iso_completions(struct fw_iso_context *base)
 	struct iso_context *ctx = container_of(base, struct iso_context, base);
 	int ret = 0;
 
-	tasklet_disable(&ctx->context.tasklet);
+	tasklet_disable_in_atomic(&ctx->context.tasklet);
 
 	if (!test_and_set_bit_lock(0, &ctx->flushing_completions)) {
 		context_tasklet((unsigned long)&ctx->context);

@@ -332,7 +332,7 @@ static int __init arc_rimi_init(void)
 		dev->irq = 9;
 
 	if (arcrimi_probe(dev)) {
-		free_netdev(dev);
+		free_arcdev(dev);
 		return -EIO;
 	}
 

@@ -349,7 +349,7 @@ static void __exit arc_rimi_exit(void)
 	iounmap(lp->mem_start);
 	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
 	free_irq(dev->irq, dev);
-	free_netdev(dev);
+	free_arcdev(dev);
 }
 
 #ifndef MODULE

@@ -298,6 +298,10 @@ struct arcnet_local {
 
 	int excnak_pending;    /* We just got an excesive nak interrupt */
 
+	/* RESET flag handling */
+	int reset_in_progress;
+	struct work_struct reset_work;
+
 	struct {
 		uint16_t sequence;	/* sequence number (incs with each packet) */
 		__be16 aborted_seq;

@@ -350,7 +354,9 @@ void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc)
 
 void arcnet_unregister_proto(struct ArcProto *proto);
 irqreturn_t arcnet_interrupt(int irq, void *dev_id);
+
 struct net_device *alloc_arcdev(const char *name);
+void free_arcdev(struct net_device *dev);
 
 int arcnet_open(struct net_device *dev);
 int arcnet_close(struct net_device *dev);

@@ -387,10 +387,44 @@ static void arcnet_timer(struct timer_list *t)
 	struct arcnet_local *lp = from_timer(lp, t, timer);
 	struct net_device *dev = lp->dev;
 
-	if (!netif_carrier_ok(dev)) {
+	spin_lock_irq(&lp->lock);
+
+	if (!lp->reset_in_progress && !netif_carrier_ok(dev)) {
 		netif_carrier_on(dev);
 		netdev_info(dev, "link up\n");
 	}
+
+	spin_unlock_irq(&lp->lock);
+}
+
+static void reset_device_work(struct work_struct *work)
+{
+	struct arcnet_local *lp;
+	struct net_device *dev;
+
+	lp = container_of(work, struct arcnet_local, reset_work);
+	dev = lp->dev;
+
+	/* Do not bring the network interface back up if an ifdown
+	 * was already done.
+	 */
+	if (!netif_running(dev) || !lp->reset_in_progress)
+		return;
+
+	rtnl_lock();
+
+	/* Do another check, in case of an ifdown that was triggered in
+	 * the small race window between the exit condition above and
+	 * acquiring RTNL.
+	 */
+	if (!netif_running(dev) || !lp->reset_in_progress)
+		goto out;
+
+	dev_close(dev);
+	dev_open(dev, NULL);
+
+out:
+	rtnl_unlock();
 }
 
 static void arcnet_reply_tasklet(unsigned long data)

@@ -452,12 +486,25 @@ struct net_device *alloc_arcdev(const char *name)
 		lp->dev = dev;
 		spin_lock_init(&lp->lock);
 		timer_setup(&lp->timer, arcnet_timer, 0);
+		INIT_WORK(&lp->reset_work, reset_device_work);
 	}
 
 	return dev;
 }
 EXPORT_SYMBOL(alloc_arcdev);
 
+void free_arcdev(struct net_device *dev)
+{
+	struct arcnet_local *lp = netdev_priv(dev);
+
+	/* Do not cancel this at ->ndo_close(), as the workqueue itself
+	 * indirectly calls the ifdown path through dev_close().
+	 */
+	cancel_work_sync(&lp->reset_work);
+	free_netdev(dev);
+}
+EXPORT_SYMBOL(free_arcdev);
+
 /* Open/initialize the board.  This is called sometime after booting when
  * the 'ifconfig' program is run.
  *

@@ -587,6 +634,10 @@ int arcnet_close(struct net_device *dev)
 
 	/* shut down the card */
 	lp->hw.close(dev);
+
+	/* reset counters */
+	lp->reset_in_progress = 0;
+
 	module_put(lp->hw.owner);
 	return 0;
 }

@@ -820,6 +871,9 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 
 	spin_lock_irqsave(&lp->lock, flags);
 
+	if (lp->reset_in_progress)
+		goto out;
+
 	/* RESET flag was enabled - if device is not running, we must
 	 * clear it right away (but nothing else).
 	 */

@@ -852,11 +906,14 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 		if (status & RESETflag) {
 			arc_printk(D_NORMAL, dev, "spurious reset (status=%Xh)\n",
 				   status);
-			arcnet_close(dev);
-			arcnet_open(dev);
+
+			lp->reset_in_progress = 1;
+			netif_stop_queue(dev);
+			netif_carrier_off(dev);
+			schedule_work(&lp->reset_work);
 
 			/* get out of the interrupt handler! */
-			break;
+			goto out;
 		}
 		/* RX is inhibited - we must have received something.
 		 * Prepare to receive into the next buffer.

@@ -1052,6 +1109,7 @@ irqreturn_t arcnet_interrupt(int irq, void *dev_id)
 	udelay(1);
 	lp->hw.intmask(dev, lp->intmask);
 
+out:
 	spin_unlock_irqrestore(&lp->lock, flags);
 	return retval;
 }

@@ -169,7 +169,7 @@ static int __init com20020_init(void)
 		dev->irq = 9;
 
 	if (com20020isa_probe(dev)) {
-		free_netdev(dev);
+		free_arcdev(dev);
 		return -EIO;
 	}
 

@@ -182,7 +182,7 @@ static void __exit com20020_exit(void)
 	unregister_netdev(my_dev);
 	free_irq(my_dev->irq, my_dev);
 	release_region(my_dev->base_addr, ARCNET_TOTAL_SIZE);
-	free_netdev(my_dev);
+	free_arcdev(my_dev);
 }
 
 #ifndef MODULE

@@ -291,7 +291,7 @@ static void com20020pci_remove(struct pci_dev *pdev)
 
 		unregister_netdev(dev);
 		free_irq(dev->irq, dev);
-		free_netdev(dev);
+		free_arcdev(dev);
 	}
 }
 

@@ -177,7 +177,7 @@ static void com20020_detach(struct pcmcia_device *link)
 		dev = info->dev;
 		if (dev) {
 			dev_dbg(&link->dev, "kfree...\n");
-			free_netdev(dev);
+			free_arcdev(dev);
 		}
 		dev_dbg(&link->dev, "kfree2...\n");
 		kfree(info);

@@ -396,7 +396,7 @@ static int __init com90io_init(void)
 	err = com90io_probe(dev);
 
 	if (err) {
-		free_netdev(dev);
+		free_arcdev(dev);
 		return err;
 	}
 

@@ -419,7 +419,7 @@ static void __exit com90io_exit(void)
 
 	free_irq(dev->irq, dev);
 	release_region(dev->base_addr, ARCNET_TOTAL_SIZE);
-	free_netdev(dev);
+	free_arcdev(dev);
 }
 
 module_init(com90io_init)

@@ -554,7 +554,7 @@ static int __init com90xx_found(int ioaddr, int airq, u_long shmem,
 err_release_mem:
 	release_mem_region(dev->mem_start, dev->mem_end - dev->mem_start + 1);
 err_free_dev:
-	free_netdev(dev);
+	free_arcdev(dev);
 	return -EIO;
 }
 

@@ -672,7 +672,7 @@ static void __exit com90xx_exit(void)
 		release_region(dev->base_addr, ARCNET_TOTAL_SIZE);
 		release_mem_region(dev->mem_start,
 				   dev->mem_end - dev->mem_start + 1);
-		free_netdev(dev);
+		free_arcdev(dev);
 	}
 }
 

@@ -963,7 +963,7 @@ static void tx_timeout(struct net_device *dev, unsigned int txqueue)
 	unsigned long flag;
 
 	netif_stop_queue(dev);
-	tasklet_disable(&np->tx_tasklet);
+	tasklet_disable_in_atomic(&np->tx_tasklet);
 	iowrite16(0, ioaddr + IntrEnable);
 	printk(KERN_WARNING "%s: Transmit timed out, TxStatus %2.2x "
 		   "TxFrameId %2.2x,"

@@ -1265,9 +1265,9 @@ jme_stop_shutdown_timer(struct jme_adapter *jme)
 	jwrite32f(jme, JME_APMC, apmc);
 }
 
-static void jme_link_change_tasklet(struct tasklet_struct *t)
+static void jme_link_change_work(struct work_struct *work)
 {
-	struct jme_adapter *jme = from_tasklet(jme, t, linkch_task);
+	struct jme_adapter *jme = container_of(work, struct jme_adapter, linkch_task);
 	struct net_device *netdev = jme->dev;
 	int rc;
 

@@ -1510,7 +1510,7 @@ jme_intr_msi(struct jme_adapter *jme, u32 intrstat)
 		 * all other events are ignored
 		 */
 		jwrite32(jme, JME_IEVE, intrstat);
-		tasklet_schedule(&jme->linkch_task);
+		schedule_work(&jme->linkch_task);
 		goto out_reenable;
 	}
 

@@ -1832,7 +1832,6 @@ jme_open(struct net_device *netdev)
 	jme_clear_pm_disable_wol(jme);
 	JME_NAPI_ENABLE(jme);
 
-	tasklet_setup(&jme->linkch_task, jme_link_change_tasklet);
 	tasklet_setup(&jme->txclean_task, jme_tx_clean_tasklet);
 	tasklet_setup(&jme->rxclean_task, jme_rx_clean_tasklet);
 	tasklet_setup(&jme->rxempty_task, jme_rx_empty_tasklet);

@@ -1920,7 +1919,7 @@ jme_close(struct net_device *netdev)
 
 	JME_NAPI_DISABLE(jme);
 
-	tasklet_kill(&jme->linkch_task);
+	cancel_work_sync(&jme->linkch_task);
 	tasklet_kill(&jme->txclean_task);
 	tasklet_kill(&jme->rxclean_task);
 	tasklet_kill(&jme->rxempty_task);

@@ -3035,6 +3034,7 @@ jme_init_one(struct pci_dev *pdev,
 	atomic_set(&jme->rx_empty, 1);
 
 	tasklet_setup(&jme->pcc_task, jme_pcc_tasklet);
+	INIT_WORK(&jme->linkch_task, jme_link_change_work);
 	jme->dpi.cur = PCC_P1;
 
 	jme->reg_ghc = 0;

@@ -411,7 +411,7 @@ struct jme_adapter {
 	struct tasklet_struct	rxempty_task;
 	struct tasklet_struct	rxclean_task;
 	struct tasklet_struct	txclean_task;
-	struct tasklet_struct	linkch_task;
+	struct work_struct	linkch_task;
 	struct tasklet_struct	pcc_task;
 	unsigned long		flags;
 	u32			reg_txcs;

@@ -251,7 +251,7 @@ void ath9k_beacon_ensure_primary_slot(struct ath_softc *sc)
 	int first_slot = ATH_BCBUF;
 	int slot;
 
-	tasklet_disable(&sc->bcon_tasklet);
+	tasklet_disable_in_atomic(&sc->bcon_tasklet);
 
 	/* Find first taken slot. */
 	for (slot = 0; slot < ATH_BCBUF; slot++) {

@@ -1458,7 +1458,7 @@ static void hv_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
 	 * Prevents hv_pci_onchannelcallback() from running concurrently
 	 * in the tasklet.
 	 */
-	tasklet_disable(&channel->callback_event);
+	tasklet_disable_in_atomic(&channel->callback_event);
 
 	/*
 	 * Since this function is called with IRQ locks held, can't

@@ -669,17 +669,14 @@ static inline int tasklet_trylock(struct tasklet_struct *t)
 	return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state);
 }
 
-static inline void tasklet_unlock(struct tasklet_struct *t)
-{
-	smp_mb__before_atomic();
-	clear_bit(TASKLET_STATE_RUN, &(t)->state);
-}
-
+void tasklet_unlock(struct tasklet_struct *t);
 void tasklet_unlock_wait(struct tasklet_struct *t);
+void tasklet_unlock_spin_wait(struct tasklet_struct *t);
 #else
 static inline int tasklet_trylock(struct tasklet_struct *t) { return 1; }
 static inline void tasklet_unlock(struct tasklet_struct *t) { }
 static inline void tasklet_unlock_wait(struct tasklet_struct *t) { }
+static inline void tasklet_unlock_spin_wait(struct tasklet_struct *t) { }
 #endif
 
 extern void __tasklet_schedule(struct tasklet_struct *t);

@@ -704,6 +701,17 @@ static inline void tasklet_disable_nosync(struct tasklet_struct *t)
 	smp_mb__after_atomic();
 }
 
+/*
+ * Do not use in new code. There is no real reason to invoke this from
+ * atomic contexts.
+ */
+static inline void tasklet_disable_in_atomic(struct tasklet_struct *t)
+{
+	tasklet_disable_nosync(t);
+	tasklet_unlock_spin_wait(t);
+	smp_mb();
+}
+
 static inline void tasklet_disable(struct tasklet_struct *t)
 {
 	tasklet_disable_nosync(t);

@@ -26,6 +26,7 @@
 #include <linux/smpboot.h>
 #include <linux/tick.h>
 #include <linux/irq.h>
+#include <linux/wait_bit.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/irq.h>

@@ -150,7 +151,7 @@ static DEFINE_PER_CPU(struct softirq_ctrl, softirq_ctrl) = {
  */
 bool local_bh_blocked(void)
 {
-	return this_cpu_read(softirq_ctrl.cnt) != 0;
+	return __this_cpu_read(softirq_ctrl.cnt) != 0;
 }
 
 void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)

@@ -224,7 +225,7 @@ void __local_bh_enable_ip(unsigned long ip, unsigned int cnt)
 	lockdep_assert_irqs_enabled();
 
 	local_irq_save(flags);
-	curcnt = this_cpu_read(softirq_ctrl.cnt);
+	curcnt = __this_cpu_read(softirq_ctrl.cnt);
 
 	/*
 	 * If this is not reenabling soft interrupts, no point in trying to

@@ -743,6 +744,16 @@ void __tasklet_hi_schedule(struct tasklet_struct *t)
 }
 EXPORT_SYMBOL(__tasklet_hi_schedule);
 
+static inline bool tasklet_clear_sched(struct tasklet_struct *t)
+{
+	if (test_and_clear_bit(TASKLET_STATE_SCHED, &t->state)) {
+		wake_up_var(&t->state);
+		return true;
+	}
+
+	return false;
+}
+
 static void tasklet_action_common(struct softirq_action *a,
 				  struct tasklet_head *tl_head,
 				  unsigned int softirq_nr)

@@ -762,8 +773,7 @@ static void tasklet_action_common(struct softirq_action *a,
 
 		if (tasklet_trylock(t)) {
 			if (!atomic_read(&t->count)) {
-				if (!test_and_clear_bit(TASKLET_STATE_SCHED,
-							&t->state))
+				if (!tasklet_clear_sched(t))
 					BUG();
 				if (t->use_callback)
 					t->callback(t);

@@ -819,8 +829,11 @@ void tasklet_init(struct tasklet_struct *t,
 EXPORT_SYMBOL(tasklet_init);
 
 #if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
-
-void tasklet_unlock_wait(struct tasklet_struct *t)
+/*
+ * Do not use in new code. There is no real reason to invoke this from
+ * atomic contexts.
+ */
+void tasklet_unlock_spin_wait(struct tasklet_struct *t)
 {
 	while (test_bit(TASKLET_STATE_RUN, &(t)->state)) {
 		if (IS_ENABLED(CONFIG_PREEMPT_RT)) {

@@ -838,7 +851,7 @@ void tasklet_unlock_wait(struct tasklet_struct *t)
 		}
 	}
 }
-EXPORT_SYMBOL(tasklet_unlock_wait);
+EXPORT_SYMBOL(tasklet_unlock_spin_wait);
 #endif
 
 void tasklet_kill(struct tasklet_struct *t)

@@ -846,29 +859,31 @@ void tasklet_kill(struct tasklet_struct *t)
 	if (in_interrupt())
 		pr_notice("Attempt to kill tasklet from interrupt\n");
 
-	while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) {
-		do {
-			if (IS_ENABLED(CONFIG_PREEMPT_RT)) {
-				/*
-				 * Prevent a live lock when current
-				 * preempted soft interrupt processing or
-				 * prevents ksoftirqd from running. If the
-				 * tasklet runs on a different CPU then
-				 * this has no effect other than doing the
-				 * BH disable/enable dance for nothing.
-				 */
-				local_bh_disable();
-				local_bh_enable();
-			} else {
-				yield();
-			}
-		} while (test_bit(TASKLET_STATE_SCHED, &t->state));
-	}
+	while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state))
+		wait_var_event(&t->state, !test_bit(TASKLET_STATE_SCHED, &t->state));
+
 	tasklet_unlock_wait(t);
-	clear_bit(TASKLET_STATE_SCHED, &t->state);
+	tasklet_clear_sched(t);
 }
 EXPORT_SYMBOL(tasklet_kill);
 
+#ifdef CONFIG_SMP
+void tasklet_unlock(struct tasklet_struct *t)
+{
+	smp_mb__before_atomic();
+	clear_bit(TASKLET_STATE_RUN, &t->state);
+	smp_mb__after_atomic();
+	wake_up_var(&t->state);
+}
+EXPORT_SYMBOL_GPL(tasklet_unlock);
+
+void tasklet_unlock_wait(struct tasklet_struct *t)
+{
+	wait_var_event(&t->state, !test_bit(TASKLET_STATE_RUN, &t->state));
+}
+EXPORT_SYMBOL_GPL(tasklet_unlock_wait);
+#endif
+
 void __init softirq_init(void)
 {
 	int cpu;

@@ -1 +1 @@
--rt2
+-rt3