xen: implement IRQ_WORK_VECTOR handler

Signed-off-by: Lin Ming <mlin@ss.pku.edu.cn>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 2dc6628c1520..3ec3f8eb19fc 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -16,6 +16,7 @@
 #include <linux/err.h>
 #include <linux/slab.h>
 #include <linux/smp.h>
+#include <linux/irq_work.h>
 
 #include <asm/paravirt.h>
 #include <asm/desc.h>
@@ -41,10 +42,12 @@ cpumask_var_t xen_cpu_initialized_map;
 static DEFINE_PER_CPU(int, xen_resched_irq);
 static DEFINE_PER_CPU(int, xen_callfunc_irq);
 static DEFINE_PER_CPU(int, xen_callfuncsingle_irq);
+static DEFINE_PER_CPU(int, xen_irq_work);
 static DEFINE_PER_CPU(int, xen_debug_irq) = -1;
 
 static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
 static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id);
+static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id);
 
 /*
  * Reschedule call back.
@@ -143,6 +146,17 @@ static int xen_smp_intr_init(unsigned int cpu)
                 goto fail;
         per_cpu(xen_callfuncsingle_irq, cpu) = rc;
 
+        callfunc_name = kasprintf(GFP_KERNEL, "irqwork%d", cpu);
+        rc = bind_ipi_to_irqhandler(XEN_IRQ_WORK_VECTOR,
+                                    cpu,
+                                    xen_irq_work_interrupt,
+                                    IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
+                                    callfunc_name,
+                                    NULL);
+        if (rc < 0)
+                goto fail;
+        per_cpu(xen_irq_work, cpu) = rc;
+
         return 0;
 
  fail:
@@ -155,6 +169,8 @@ static int xen_smp_intr_init(unsigned int cpu)
         if (per_cpu(xen_callfuncsingle_irq, cpu) >= 0)
                 unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu),
                                        NULL);
+        if (per_cpu(xen_irq_work, cpu) >= 0)
+                unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL);
 
         return rc;
 }
@@ -509,6 +525,9 @@ static inline int xen_map_vector(int vector)
         case CALL_FUNCTION_SINGLE_VECTOR:
                 xen_vector = XEN_CALL_FUNCTION_SINGLE_VECTOR;
                 break;
+        case IRQ_WORK_VECTOR:
+                xen_vector = XEN_IRQ_WORK_VECTOR;
+                break;
         default:
                 xen_vector = -1;
                 printk(KERN_ERR "xen: vector 0x%x is not implemented\n",
@@ -588,6 +607,16 @@ static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
         return IRQ_HANDLED;
 }
 
+static irqreturn_t xen_irq_work_interrupt(int irq, void *dev_id)
+{
+        irq_enter();
+        irq_work_run();
+        inc_irq_stat(apic_irq_work_irqs);
+        irq_exit();
+
+        return IRQ_HANDLED;
+}
+
 static const struct smp_ops xen_smp_ops __initconst = {
         .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
         .smp_prepare_cpus = xen_smp_prepare_cpus,
@@ -634,6 +663,7 @@ static void xen_hvm_cpu_die(unsigned int cpu)
         unbind_from_irqhandler(per_cpu(xen_callfunc_irq, cpu), NULL);
         unbind_from_irqhandler(per_cpu(xen_debug_irq, cpu), NULL);
         unbind_from_irqhandler(per_cpu(xen_callfuncsingle_irq, cpu), NULL);
+        unbind_from_irqhandler(per_cpu(xen_irq_work, cpu), NULL);
         native_cpu_die(cpu);
 }