Merge tag 'irq-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq updates from Thomas Gleixner:
 "The interrupt departement provides:

   - A mechanism to shield isolated tasks from managed interrupts:

     The affinity of managed interrupts is completely controlled by the
     kernel and user space has no influence on them. The reason is that
     the automatically assigned affinity correlates to the multi-queue
     CPU handling of block devices.

     If the generated affinity mask spaws both housekeeping and isolated
     CPUs the interrupt could be routed to an isolated CPU which would
     then be disturbed by I/O submitted by a housekeeping CPU.

     The new mechamism ensures that as long as one housekeeping CPU is
     online in the assigned affinity mask the interrupt is routed to a
     housekeeping CPU.

     If there is no online housekeeping CPU in the affinity mask, then
     the interrupt is routed to an isolated CPU to keep the device queue
     intact, but unless the isolated CPU submits I/O by itself these
     interrupts are not raised.

   - A small addon to the device tree irqdomain core code to avoid
     duplication in irq chip drivers

   - Conversion of the SiFive PLIC to hierarchical domains

   - The usual pile of new irq chip drivers: SiFive GPIO, Aspeed SCI,
     NXP INTMUX, Meson A1 GPIO

   - The first cut of support for the new ARM GICv4.1

   - The usual pile of fixes and improvements in core and driver code"

* tag 'irq-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  genirq, sched/isolation: Isolate from handling managed interrupts
  irqchip/gic-v4.1: Allow direct invalidation of VLPIs
  irqchip/gic-v4.1: Suppress per-VLPI doorbell
  irqchip/gic-v4.1: Add VPE INVALL callback
  irqchip/gic-v4.1: Add VPE eviction callback
  irqchip/gic-v4.1: Add VPE residency callback
  irqchip/gic-v4.1: Add mask/unmask doorbell callbacks
  irqchip/gic-v4.1: Plumb skeletal VPE irqchip
  irqchip/gic-v4.1: Implement the v4.1 flavour of VMOVP
  irqchip/gic-v4.1: Don't use the VPE proxy if RVPEID is set
  irqchip/gic-v4.1: Implement the v4.1 flavour of VMAPP
  irqchip/gic-v4.1: VPE table (aka GICR_VPROPBASER) allocation
  irqchip/gic-v3: Add GICv4.1 VPEID size discovery
  irqchip/gic-v3: Detect GICv4.1 supporting RVPEID
  irqchip/gic-v3-its: Fix get_vlpi_map() breakage with doorbells
  irqdomain: Fix a memory leak in irq_domain_push_irq()
  irqchip: Add NXP INTMUX interrupt multiplexer support
  dt-bindings: interrupt-controller: Add binding for NXP INTMUX interrupt multiplexer
  irqchip: Define EXYNOS_IRQ_COMBINER
  irqchip/meson-gpio: Add support for meson a1 SoCs
  ...

6 files changed, 87 insertions, 5 deletions

diff --git a/kernel/irq/cpuhotplug.c b/kernel/irq/cpuhotplug.c
index 6c7ca2e983a5..02236b13b359 100644
--- a/kernel/irq/cpuhotplug.c
+++ b/kernel/irq/cpuhotplug.c
@@ -12,6 +12,7 @@
 #include <linux/interrupt.h>
 #include <linux/ratelimit.h>
 #include <linux/irq.h>
+#include <linux/sched/isolation.h>
 
 #include "internals.h"
 
@@ -171,6 +172,20 @@ void irq_migrate_all_off_this_cpu(void)
 	}
 }
 
+static bool hk_should_isolate(struct irq_data *data, unsigned int cpu)
+{
+	const struct cpumask *hk_mask;
+
+	if (!housekeeping_enabled(HK_FLAG_MANAGED_IRQ))
+		return false;
+
+	hk_mask = housekeeping_cpumask(HK_FLAG_MANAGED_IRQ);
+	if (cpumask_subset(irq_data_get_effective_affinity_mask(data), hk_mask))
+		return false;
+
+	return cpumask_test_cpu(cpu, hk_mask);
+}
+
 static void irq_restore_affinity_of_irq(struct irq_desc *desc, unsigned int cpu)
 {
 	struct irq_data *data = irq_desc_get_irq_data(desc);
@@ -188,9 +203,11 @@ static void irq_restore_affinity_of_irq(struct irq_desc *desc, unsigned int cpu)
 	/*
 	 * If the interrupt can only be directed to a single target
 	 * CPU then it is already assigned to a CPU in the affinity
-	 * mask. No point in trying to move it around.
+	 * mask. No point in trying to move it around unless the
+	 * isolation mechanism requests to move it to an upcoming
+	 * housekeeping CPU.
 	 */
-	if (!irqd_is_single_target(data))
+	if (!irqd_is_single_target(data) || hk_should_isolate(data, cpu))
 		irq_set_affinity_locked(data, affinity, false);
 }
 
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 5b8fdd659e54..98a5f10d1900 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -891,6 +891,7 @@ __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
 }
 
 void __irq_put_desc_unlock(struct irq_desc *desc, unsigned long flags, bool bus)
+	__releases(&desc->lock)
 {
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
 	if (bus)
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index dd822fd8a7d5..7527e5ef6fe5 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -987,6 +987,23 @@ const struct irq_domain_ops irq_domain_simple_ops = {
 EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
 
 /**
+ * irq_domain_translate_onecell() - Generic translate for direct one cell
+ * bindings
+ */
+int irq_domain_translate_onecell(struct irq_domain *d,
+				 struct irq_fwspec *fwspec,
+				 unsigned long *out_hwirq,
+				 unsigned int *out_type)
+{
+	if (WARN_ON(fwspec->param_count < 1))
+		return -EINVAL;
+	*out_hwirq = fwspec->param[0];
+	*out_type = IRQ_TYPE_NONE;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(irq_domain_translate_onecell);
+
+/**
  * irq_domain_translate_twocell() - Generic translate for direct two cell
  * bindings
  *
@@ -1459,6 +1476,7 @@ int irq_domain_push_irq(struct irq_domain *domain, int virq, void *arg)
 	if (rv) {
 		/* Restore the original irq_data. */
 		*root_irq_data = *child_irq_data;
+		kfree(child_irq_data);
 		goto error;
 	}
 
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 1753486b440c..818b2802d3e7 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -18,6 +18,7 @@
 #include <linux/sched.h>
 #include <linux/sched/rt.h>
 #include <linux/sched/task.h>
+#include <linux/sched/isolation.h>
 #include <uapi/linux/sched/types.h>
 #include <linux/task_work.h>
 
@@ -217,7 +218,45 @@ int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask,
 	if (!chip || !chip->irq_set_affinity)
 		return -EINVAL;
 
-	ret = chip->irq_set_affinity(data, mask, force);
+	/*
+	 * If this is a managed interrupt and housekeeping is enabled on
+	 * it check whether the requested affinity mask intersects with
+	 * a housekeeping CPU. If so, then remove the isolated CPUs from
+	 * the mask and just keep the housekeeping CPU(s). This prevents
+	 * the affinity setter from routing the interrupt to an isolated
+	 * CPU to avoid that I/O submitted from a housekeeping CPU causes
+	 * interrupts on an isolated one.
+	 *
+	 * If the masks do not intersect or include online CPU(s) then
+	 * keep the requested mask. The isolated target CPUs are only
+	 * receiving interrupts when the I/O operation was submitted
+	 * directly from them.
+	 *
+	 * If all housekeeping CPUs in the affinity mask are offline, the
+	 * interrupt will be migrated by the CPU hotplug code once a
+	 * housekeeping CPU which belongs to the affinity mask comes
+	 * online.
+	 */
+	if (irqd_affinity_is_managed(data) &&
+	    housekeeping_enabled(HK_FLAG_MANAGED_IRQ)) {
+		const struct cpumask *hk_mask, *prog_mask;
+
+		static DEFINE_RAW_SPINLOCK(tmp_mask_lock);
+		static struct cpumask tmp_mask;
+
+		hk_mask = housekeeping_cpumask(HK_FLAG_MANAGED_IRQ);
+
+		raw_spin_lock(&tmp_mask_lock);
+		cpumask_and(&tmp_mask, mask, hk_mask);
+		if (!cpumask_intersects(&tmp_mask, cpu_online_mask))
+			prog_mask = mask;
+		else
+			prog_mask = &tmp_mask;
+		ret = chip->irq_set_affinity(data, prog_mask, force);
+		raw_spin_unlock(&tmp_mask_lock);
+	} else {
+		ret = chip->irq_set_affinity(data, mask, force);
+	}
 	switch (ret) {
 	case IRQ_SET_MASK_OK:
 	case IRQ_SET_MASK_OK_DONE:
@@ -1500,8 +1539,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 		 * has. The type flags are unreliable as the
 		 * underlying chip implementation can override them.
 		 */
-		pr_err("Threaded irq requested with handler=NULL and !ONESHOT for irq %d\n",
-		       irq);
+		pr_err("Threaded irq requested with handler=NULL and !ONESHOT for %s (irq %d)\n",
+		       new->name, irq);
 		ret = -EINVAL;
 		goto out_unlock;
 	}
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index 2ed97a7c9b2a..f865e5f4d382 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -34,6 +34,7 @@ static atomic_t irq_poll_active;
  * true and let the handler run.
  */
 bool irq_wait_for_poll(struct irq_desc *desc)
+	__must_hold(&desc->lock)
 {
 	if (WARN_ONCE(irq_poll_cpu == smp_processor_id(),
 		      "irq poll in progress on cpu %d for irq %d\n",
diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c
index 9fcb2a695a41..008d6ac2342b 100644
--- a/kernel/sched/isolation.c
+++ b/kernel/sched/isolation.c
@@ -163,6 +163,12 @@ static int __init housekeeping_isolcpus_setup(char *str)
 			continue;
 		}
 
+		if (!strncmp(str, "managed_irq,", 12)) {
+			str += 12;
+			flags |= HK_FLAG_MANAGED_IRQ;
+			continue;
+		}
+
 		pr_warn("isolcpus: Error, unknown flag\n");
 		return 0;
 	}