7 files changed, 38 insertions, 41 deletions

diff --git a/arch/x86/kernel/io_apic_64.c b/arch/x86/kernel/io_apic_64.c
index 1b8cccb5ba25..a054db9ef190 100644
--- a/arch/x86/kernel/io_apic_64.c
+++ b/arch/x86/kernel/io_apic_64.c
@@ -1124,7 +1124,12 @@ static void ioapic_register_intr(int irq, unsigned long trigger)
 {
         struct irq_desc *desc;
 
-        desc = irq_to_desc(irq);
+        /* first time to use this irq_desc */
+        if (irq < 16)
+                desc = irq_to_desc(irq);
+        else
+                desc = irq_to_desc_alloc(irq);
+
         if (trigger)
                 desc->status |= IRQ_LEVEL;
         else
@@ -1919,6 +1924,9 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void)
                 irq = __get_cpu_var(vector_irq)[vector];
 
                 desc = irq_to_desc(irq);
+                if (!desc)
+                        continue;
+
                 cfg = irq_cfg(irq);
                 spin_lock(&desc->lock);
                 if (!cfg->move_cleanup_count)
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index f337f87c1e16..5d5976e0311a 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -83,7 +83,7 @@ int show_interrupts(struct seq_file *p, void *v)
 
         if (i < nr_irqs) {
                 unsigned any_count = 0;
-                struct irq_desc *desc = __irq_to_desc(i);
+                struct irq_desc *desc = irq_to_desc(i);
 
                 if (!desc)
                         return 0;
@@ -206,7 +206,7 @@ asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
         stack_overflow_check(regs);
 #endif
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (likely(desc))
                 generic_handle_irq_desc(irq, desc);
         else {
diff --git a/arch/x86/kernel/irqinit_64.c b/arch/x86/kernel/irqinit_64.c
index cd9f42d028d9..d17fbc26d96f 100644
--- a/arch/x86/kernel/irqinit_64.c
+++ b/arch/x86/kernel/irqinit_64.c
@@ -143,7 +143,8 @@ void __init init_ISA_irqs(void)
         init_8259A(0);
 
         for (i = 0; i < 16; i++) {
-                struct irq_desc *desc = irq_to_desc(i);
+                /* first time call this irq_desc */
+                struct irq_desc *desc = irq_to_desc_alloc(i);
 
                 desc->status = IRQ_DISABLED;
                 desc->action = NULL;
diff --git a/include/linux/irq.h b/include/linux/irq.h
index 7b59e193a119..5fe1b01c11fe 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -191,7 +191,7 @@ struct irq_desc {
 } ____cacheline_internodealigned_in_smp;
 
 extern struct irq_desc *irq_to_desc(unsigned int irq);
-extern struct irq_desc *__irq_to_desc(unsigned int irq);
+extern struct irq_desc *irq_to_desc_alloc(unsigned int irq);
 
 #ifndef CONFIG_HAVE_SPARSE_IRQ
 
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index a4bb0da9c88c..9fc5e69213de 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -27,7 +27,8 @@ void dynamic_irq_init(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = irq_to_desc(irq);
+        /* first time to use this irq_desc */
+        desc = irq_to_desc_alloc(irq);
         if (!desc) {
                 WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
                 return;
@@ -60,7 +61,7 @@ void dynamic_irq_cleanup(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc) {
                 WARN(1, KERN_ERR "Trying to cleanup invalid IRQ%d\n", irq);
                 return;
@@ -92,7 +93,7 @@ int set_irq_chip(unsigned int irq, struct irq_chip *chip)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc) {
                 WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq);
                 return -EINVAL;
@@ -122,7 +123,7 @@ int set_irq_type(unsigned int irq, unsigned int type)
         unsigned long flags;
         int ret = -ENXIO;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc) {
                 printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
                 return -ENODEV;
@@ -150,7 +151,7 @@ int set_irq_data(unsigned int irq, void *data)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc) {
                 printk(KERN_ERR
                        "Trying to install controller data for IRQ%d\n", irq);
@@ -176,7 +177,7 @@ int set_irq_msi(unsigned int irq, struct msi_desc *entry)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc) {
                 printk(KERN_ERR
                        "Trying to install msi data for IRQ%d\n", irq);
@@ -203,7 +204,7 @@ int set_irq_chip_data(unsigned int irq, void *data)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc) {
                 printk(KERN_ERR
                        "Trying to install chip data for IRQ%d\n", irq);
@@ -554,7 +555,7 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc) {
                 printk(KERN_ERR
                        "Trying to install type control for IRQ%d\n", irq);
@@ -618,7 +619,7 @@ void __init set_irq_noprobe(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc) {
                 printk(KERN_ERR "Trying to mark IRQ%d non-probeable\n", irq);
 
@@ -635,7 +636,7 @@ void __init set_irq_probe(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc) {
                 printk(KERN_ERR "Trying to mark IRQ%d probeable\n", irq);
 
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index e1d787e9169b..d44e3515eae1 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -151,7 +151,7 @@ early_param("nr_irq_desc", parse_nr_irq_desc);
 struct irq_desc *sparse_irqs;
 DEFINE_DYN_ARRAY(sparse_irqs, sizeof(struct irq_desc), nr_irq_desc, PAGE_SIZE, init_work);
 
-struct irq_desc *__irq_to_desc(unsigned int irq)
+struct irq_desc *irq_to_desc(unsigned int irq)
 {
         struct irq_desc *desc;
 
@@ -169,7 +169,7 @@ struct irq_desc *__irq_to_desc(unsigned int irq)
         }
         return NULL;
 }
-struct irq_desc *irq_to_desc(unsigned int irq)
+struct irq_desc *irq_to_desc_alloc(unsigned int irq)
 {
         struct irq_desc *desc, *desc_pri;
         int i;
@@ -186,6 +186,7 @@ struct irq_desc *irq_to_desc(unsigned int irq)
 
                 if (desc->irq == -1U) {
                         desc->irq = irq;
+                        printk(KERN_DEBUG "found new irq_desc for irq %d\n", desc->irq);
                         return desc;
                 }
                 desc_pri = desc;
@@ -236,21 +237,7 @@ struct irq_desc *irq_to_desc(unsigned int irq)
 
         desc->irq = irq;
         desc_pri->next = desc;
-        {
-                /* double check if some one mess up the list */
-                struct irq_desc *desc;
-                int count = 0;
-
-                desc = &sparse_irqs[0];
-                while (desc) {
-                        printk(KERN_DEBUG "1 found irq_desc for irq %d\n", desc->irq);
-                        if (desc->next)
-                                printk(KERN_DEBUG "1 found irq_desc for irq %d and next will be irq %d\n", desc->irq, desc->next->irq);
-                        desc = desc->next;
-                        count++;
-                }
-                printk(KERN_DEBUG "1 all preallocted %d\n", count);
-        }
+        printk(KERN_DEBUG "1 found new irq_desc for irq %d and pri will be irq %d\n", desc->irq, desc_pri->irq);
 
         return desc;
 }
@@ -285,7 +272,7 @@ struct irq_desc *irq_to_desc(unsigned int irq)
 
         return NULL;
 }
-struct irq_desc *__irq_to_desc(unsigned int irq)
+struct irq_desc *irq_to_desc_alloc(unsigned int irq)
 {
         return irq_to_desc(irq);
 }
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index c0b4d4df6de2..6df49218632a 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -31,7 +31,7 @@ cpumask_t irq_default_affinity = CPU_MASK_ALL;
  */
 void synchronize_irq(unsigned int irq)
 {
-        struct irq_desc *desc = __irq_to_desc(irq);
+        struct irq_desc *desc = irq_to_desc(irq);
         unsigned int status;
 
         if (!desc)
@@ -145,7 +145,7 @@ void disable_irq_nosync(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc)
                 return;
 
@@ -174,7 +174,7 @@ void disable_irq(unsigned int irq)
 {
         struct irq_desc *desc;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc)
                 return;
 
@@ -218,7 +218,7 @@ void enable_irq(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc)
                 return;
 
@@ -296,7 +296,7 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
         struct irq_desc *desc;
         struct irqaction *action;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc)
                 return 0;
 
@@ -366,7 +366,7 @@ int setup_irq(unsigned int irq, struct irqaction *new)
         int shared = 0;
         int ret;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc)
                 return -EINVAL;
 
@@ -527,7 +527,7 @@ void free_irq(unsigned int irq, void *dev_id)
 
         WARN_ON(in_interrupt());
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc)
                 return;
 
@@ -644,7 +644,7 @@ int request_irq(unsigned int irq, irq_handler_t handler,
         if ((irqflags & IRQF_SHARED) && !dev_id)
                 return -EINVAL;
 
-        desc = __irq_to_desc(irq);
+        desc = irq_to_desc(irq);
         if (!desc)
                 return -EINVAL;