x86: move kstat_irqs from kstat to irq_desc

based on Eric's patch ...

together mold it with dyn_array for irq_desc, will allcate kstat_irqs for
nr_irq_desc alltogether if needed. -- at that point nr_cpus is known already.

v2: make sure system without generic_hardirqs works they don't have irq_desc
v3: fix merging
v4: [mingo@elte.hu] fix typo

[ mingo@elte.hu ] irq: build fix

fix:

 arch/x86/xen/spinlock.c: In function 'xen_spin_lock_slow':
 arch/x86/xen/spinlock.c:90: error: 'struct kernel_stat' has no member named 'irqs'

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 70 insertions, 27 deletions

diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 9fc33b3378e6..1f346990f3f8 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -37,7 +37,7 @@ void
 handle_bad_irq(unsigned int irq, struct irq_desc *desc)
 {
         print_irq_desc(irq, desc);
-        kstat_this_cpu.irqs[irq]++;
+        kstat_irqs_this_cpu(desc)++;
         ack_bad_irq(irq);
 }
 
@@ -80,17 +80,38 @@ static void init_one_irq_desc(struct irq_desc *desc)
 #endif
 }
 
-#ifdef CONFIG_HAVE_SPARSE_IRQ
-static int nr_irq_desc = 32;
+extern int after_bootmem;
+extern void *__alloc_bootmem_nopanic(unsigned long size,
+                             unsigned long align,
+                             unsigned long goal);
 
-static int __init parse_nr_irq_desc(char *arg)
+static void init_kstat_irqs(struct irq_desc *desc, int nr_desc, int nr)
 {
-        if (arg)
-                nr_irq_desc = simple_strtoul(arg, NULL, 0);
-        return 0;
+        unsigned long bytes, total_bytes;
+        char *ptr;
+        int i;
+        unsigned long phys;
+
+        /* Compute how many bytes we need per irq and allocate them */
+        bytes = nr * sizeof(unsigned int);
+        total_bytes = bytes * nr_desc;
+        if (after_bootmem)
+                ptr = kzalloc(total_bytes, GFP_ATOMIC);
+        else
+                ptr = __alloc_bootmem_nopanic(total_bytes, PAGE_SIZE, 0);
+
+        if (!ptr)
+                panic(" can not allocate kstat_irqs\n");
+
+        phys = __pa(ptr);
+        printk(KERN_DEBUG "kstat_irqs ==> [%#lx - %#lx]\n", phys, phys + total_bytes);
+
+        for (i = 0; i < nr_desc; i++) {
+                desc[i].kstat_irqs = (unsigned int *)ptr;
+                ptr += bytes;
+        }
 }
 
-early_param("nr_irq_desc", parse_nr_irq_desc);
 
 static void __init init_work(void *data)
 {
@@ -100,25 +121,44 @@ static void __init init_work(void *data)
 
         desc = *da->name;
 
-        for (i = 0; i < *da->nr; i++)
+        for (i = 0; i < *da->nr; i++) {
                 init_one_irq_desc(&desc[i]);
+#ifndef CONFIG_HAVE_SPARSE_IRQ
+                desc[i].irq = i;
+#endif
+        }
 
+#ifdef CONFIG_HAVE_SPARSE_IRQ
         for (i = 1; i < *da->nr; i++)
                 desc[i-1].next = &desc[i];
+#endif
+
+        /* init kstat_irqs, nr_cpu_ids is ready already */
+        init_kstat_irqs(desc, *da->nr, nr_cpu_ids);
 }
 
+#ifdef CONFIG_HAVE_SPARSE_IRQ
+static int nr_irq_desc = 32;
+
+static int __init parse_nr_irq_desc(char *arg)
+{
+        if (arg)
+                nr_irq_desc = simple_strtoul(arg, NULL, 0);
+        return 0;
+}
+
+early_param("nr_irq_desc", parse_nr_irq_desc);
+
 static struct irq_desc *sparse_irqs;
 DEFINE_DYN_ARRAY(sparse_irqs, sizeof(struct irq_desc), nr_irq_desc, PAGE_SIZE, init_work);
 
-extern int after_bootmem;
-extern void *__alloc_bootmem_nopanic(unsigned long size,
-                             unsigned long align,
-                             unsigned long goal);
 struct irq_desc *irq_to_desc(unsigned int irq)
 {
         struct irq_desc *desc, *desc_pri;
         int i;
         int count = 0;
+        unsigned long phys;
+        unsigned long total_bytes;
 
         BUG_ON(irq == -1U);
 
@@ -141,38 +181,34 @@ struct irq_desc *irq_to_desc(unsigned int irq)
          */
         printk(KERN_DEBUG "try to get more irq_desc %d\n", nr_irq_desc);
 
+        total_bytes = sizeof(struct irq_desc) * nr_irq_desc;
         if (after_bootmem)
-                desc = kzalloc(sizeof(struct irq_desc)*nr_irq_desc, GFP_ATOMIC);
+                desc = kzalloc(total_bytes, GFP_ATOMIC);
         else
-                desc = __alloc_bootmem_nopanic(sizeof(struct irq_desc)*nr_irq_desc, PAGE_SIZE, 0);
+                desc = __alloc_bootmem_nopanic(total_bytes, PAGE_SIZE, 0);
 
         if (!desc)
                 panic("please boot with nr_irq_desc= %d\n", count * 2);
 
+        phys = __pa(desc);
+        printk(KERN_DEBUG "irq_desc ==> [%#lx - %#lx]\n", phys, phys + total_bytes);
+
         for (i = 0; i < nr_irq_desc; i++)
                 init_one_irq_desc(&desc[i]);
 
         for (i = 1; i < nr_irq_desc; i++)
                 desc[i-1].next = &desc[i];
 
+        /* init kstat_irqs, nr_cpu_ids is ready already */
+        init_kstat_irqs(desc, nr_irq_desc, nr_cpu_ids);
+
         desc->irq = irq;
         desc_pri->next = desc;
 
         return desc;
 }
 #else
-static void __init init_work(void *data)
-{
-        struct dyn_array *da = data;
-        int i;
-        struct  irq_desc *desc;
-
-        desc = *da->name;
 
-        for (i = 0; i < *da->nr; i++)
-                init_one_irq_desc(&desc[i]);
-
-}
 static struct irq_desc *irq_desc;
 DEFINE_DYN_ARRAY(irq_desc, sizeof(struct irq_desc), nr_irqs, PAGE_SIZE, init_work);
 
@@ -315,7 +351,7 @@ unsigned int __do_IRQ(unsigned int irq)
         struct irqaction *action;
         unsigned int status;
 
-        kstat_this_cpu.irqs[irq]++;
+        kstat_irqs_this_cpu(desc)++;
         if (CHECK_IRQ_PER_CPU(desc->status)) {
                 irqreturn_t action_ret;
 
@@ -415,3 +451,10 @@ void early_init_irq_lock_class(void)
 }
 #endif
 
+unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
+{
+        struct irq_desc *desc = irq_to_desc(irq);
+        return desc->kstat_irqs[cpu];
+}
+EXPORT_SYMBOL(kstat_irqs_cpu);
+