[PATCH] KVM: add VM-exit profiling
This adds the profile=kvm boot option, which enables KVM to profile VM
exits.
Use: "readprofile -m ./System.map | sort -n" to see the resulting
output:
[...]
18246 serial_out 148.3415
18945 native_flush_tlb 378.9000
23618 serial_in 212.7748
29279 __spin_unlock_irq 622.9574
43447 native_apic_write 2068.9048
52702 enable_8259A_irq 742.2817
54250 vgacon_scroll 89.3740
67394 ide_inb 6126.7273
79514 copy_page_range 98.1654
84868 do_wp_page 86.6000
140266 pit_read 783.6089
151436 ide_outb 25239.3333
152668 native_io_delay 21809.7143
174783 mask_and_ack_8259A 783.7803
362404 native_set_pte_at 36240.4000
1688747 total 0.5009
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c
index d4701cb..ce219e3 100644
--- a/drivers/kvm/vmx.c
+++ b/drivers/kvm/vmx.c
@@ -21,6 +21,7 @@
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/highmem.h>
+#include <linux/profile.h>
#include <asm/io.h>
#include <asm/desc.h>
@@ -1859,6 +1860,12 @@
asm ("mov %0, %%ds; mov %0, %%es" : : "r"(__USER_DS));
#endif
+ /*
+ * Profile KVM exit RIPs:
+ */
+ if (unlikely(prof_on == KVM_PROFILING))
+ profile_hit(KVM_PROFILING, (void *)vmcs_readl(GUEST_RIP));
+
kvm_run->exit_type = 0;
if (fail) {
kvm_run->exit_type = KVM_EXIT_TYPE_FAIL_ENTRY;