tile/perf: Support perf_events on tilegx and tilepro

Add perf support for tile architecture.

Signed-off-by: Zhigang Lu <zlu@tilera.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>

arch/tile/kernel/Makefile

@@ -25,6 +25,7 @@ obj-$(CONFIG_PCI)		+= pci_gx.o
 else
 obj-$(CONFIG_PCI)		+= pci.o
 endif
+obj-$(CONFIG_PERF_EVENTS)	+= perf_event.o
 obj-$(CONFIG_USE_PMC)		+= pmc.o
 obj-$(CONFIG_TILE_USB)		+= usb.o
 obj-$(CONFIG_TILE_HVGLUE_TRACE)	+= hvglue_trace.o

arch/tile/kernel/irq.c

@@ -21,6 +21,7 @@
 #include <hv/drv_pcie_rc_intf.h>
 #include <arch/spr_def.h>
 #include <asm/traps.h>
+#include <linux/perf_event.h>
 
 /* Bit-flag stored in irq_desc->chip_data to indicate HW-cleared irqs. */
 #define IS_HW_CLEARED 1
@@ -260,6 +261,23 @@ void ack_bad_irq(unsigned int irq)
 	pr_err("unexpected IRQ trap at vector %02x\n", irq);
 }
 
+/*
+ * /proc/interrupts printing:
+ */
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+#ifdef CONFIG_PERF_EVENTS
+	int i;
+
+	seq_printf(p, "%*s: ", prec, "PMI");
+
+	for_each_online_cpu(i)
+		seq_printf(p, "%10llu ", per_cpu(perf_irqs, i));
+	seq_puts(p, "  perf_events\n");
+#endif
+	return 0;
+}
+
 /*
  * Generic, controller-independent functions:
  */