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>

2 files changed, 22 insertions, 7 deletions

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 60c856aaac0f..cbf471aee1ce 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -158,6 +158,11 @@ struct irq_desc {
         struct irq_desc         *next;
         struct timer_rand_state *timer_rand_state;
 #endif
+#ifdef CONFIG_HAVE_DYN_ARRAY
+        unsigned int            *kstat_irqs;
+#else
+        unsigned int            kstat_irqs[NR_CPUS];
+#endif
         irq_flow_handler_t      handle_irq;
         struct irq_chip         *chip;
         struct msi_desc         *msi_desc;
@@ -190,6 +195,8 @@ extern struct irq_desc *irq_to_desc(unsigned int irq);
 /* could be removed if we get rid of all irq_desc reference */
 extern struct irq_desc irq_desc[NR_IRQS];
 #endif
+#define kstat_irqs_this_cpu(DESC) \
+        ((DESC)->kstat_irqs[smp_processor_id()])
 
 /*
  * Migration helpers for obsolete names, they will go away:
diff --git a/include/linux/kernel_stat.h b/include/linux/kernel_stat.h
index fe1f7fe534b4..f10616712de5 100644
--- a/include/linux/kernel_stat.h
+++ b/include/linux/kernel_stat.h
@@ -28,10 +28,8 @@ struct cpu_usage_stat {
 
 struct kernel_stat {
         struct cpu_usage_stat   cpustat;
-#ifdef CONFIG_HAVE_DYN_ARRAY
-        unsigned int *irqs;
-#else
-        unsigned int irqs[NR_IRQS];
+#ifndef CONFIG_GENERIC_HARDIRQS
+       unsigned int irqs[NR_IRQS];
 #endif
 };
 
@@ -43,15 +41,25 @@ DECLARE_PER_CPU(struct kernel_stat, kstat);
 
 extern unsigned long long nr_context_switches(void);
 
+#ifndef CONFIG_GENERIC_HARDIRQS
+static inline unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
+{
+       return kstat_cpu(cpu).irqs[irq];
+}
+#else
+extern unsigned int kstat_irqs_cpu(unsigned int irq, int cpu);
+#endif
+
 /*
  * Number of interrupts per specific IRQ source, since bootup
  */
-static inline int kstat_irqs(int irq)
+static inline unsigned int kstat_irqs(unsigned int irq)
 {
-        int cpu, sum = 0;
+        unsigned int sum = 0;
+        int cpu;
 
         for_each_possible_cpu(cpu)
-                sum += kstat_cpu(cpu).irqs[irq];
+                sum += kstat_irqs_cpu(irq, cpu);
 
         return sum;
 }