[RFC][PATCH v1 08/15] perf: export tracepoint events via sysfs: kvm and kvm_mmu

[Lin Ming <ming.m.lin@intel.com>]

kvm and kvm_mmu tracepoint events are exported like below,

/sys/devices/system/kvm/kvm0/events/
|-- kvm_ack_irq
|   |-- config
|   `-- type
....
....
|-- kvm_mmu_get_page
|   |-- config
|   `-- type
....
....
---
 virt/kvm/kvm_main.c |   15 +++++++++++++++
 1 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index f032806..0acb4f6 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -46,6 +46,7 @@
 #include <linux/srcu.h>
 #include <linux/hugetlb.h>
 #include <linux/slab.h>
+#include <linux/perf_event.h>
 
 #include <asm/processor.h>
 #include <asm/io.h>
@@ -2178,6 +2179,18 @@ static void kvm_sched_out(struct preempt_notifier *pn,
 	kvm_arch_vcpu_put(vcpu);
 }
 
+static void kvm_sys_add_tp(struct kobject *kvm_kobj)
+{
+	struct kobject *events_kobj;
+
+	events_kobj = perf_sys_create_events_dir(kvm_kobj);
+	if (!events_kobj)
+		return;
+
+	perf_sys_add_tp_events(events_kobj, "kvm");
+	perf_sys_add_tp_events(events_kobj, "kvm_mmu");
+}
+
 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
 		  struct module *module)
 {
@@ -2227,6 +2240,8 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
 	if (r)
 		goto out_free_4;
 
+	kvm_sys_add_tp(&kvm_sysdev.kobj);
+
 	/* A kmem cache lets us meet the alignment requirements of fx_save. */
 	if (!vcpu_align)
 		vcpu_align = __alignof__(struct kvm_vcpu);