performance counters: x86 support

Implement performance counters for x86 Intel CPUs.

It's simplified right now: the PERFMON CPU feature is assumed,
which is available in Core2 and later Intel CPUs.

The design is flexible to be extended to more CPU types as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 5 insertions, 0 deletions

diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index d1d4dc52f649..d92bc71e41a7 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -56,6 +56,10 @@ static int show_other_interrupts(struct seq_file *p)
         for_each_online_cpu(j)
                 seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
         seq_printf(p, "  Local timer interrupts\n");
+        seq_printf(p, "CNT: ");
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", irq_stats(j)->apic_perf_irqs);
+        seq_printf(p, "  Performance counter interrupts\n");
 #endif
 #ifdef CONFIG_SMP
         seq_printf(p, "RES: ");
@@ -160,6 +164,7 @@ u64 arch_irq_stat_cpu(unsigned int cpu)
 
 #ifdef CONFIG_X86_LOCAL_APIC
         sum += irq_stats(cpu)->apic_timer_irqs;
+        sum += irq_stats(cpu)->apic_perf_irqs;
 #endif
 #ifdef CONFIG_SMP
         sum += irq_stats(cpu)->irq_resched_count;