[kvm-unit-tests] vmexit: add tests with EFER.SCE=1

Commit Message

Paolo Bonzini Nov. 10, 2014, 10:05 a.m. UTC

These activate a faster path that does not set EFER in the
user return notifier.  Time the difference between the two.

Signed-off-by: Paolo Bonzini <[e-mail]>
---
 x86/vmexit.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

Patch

diff --git a/x86/vmexit.c b/x86/vmexit.c
index 3bd0c81..a0380ab 100644
--- a/x86/vmexit.c
+++ b/x86/vmexit.c
@@ -3,6 +3,7 @@ 
 #include "processor.h"
 #include "atomic.h"
 #include "x86/vm.h"
+#include "x86/msr.h"
 #include "x86/desc.h"
 #include "x86/pci.h"
 
@@ -10,6 +11,7 @@  struct test {
 	void (*func)(void);
 	const char *name;
 	int (*valid)(void);
+	void (*after)(void);
 	int parallel;
 	bool (*next)(struct test *);
 };
@@ -119,6 +121,17 @@  static void inl_nop_kernel(void)
     inb(0x4d0);
 }
 
+static int set_sce(void)
+{
+    wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_SCE);
+    return true;
+}
+
+static void clear_sce(void)
+{
+    wrmsr(MSR_EFER, rdmsr(MSR_EFER) & ~EFER_SCE);
+}
+
 static void outl_elcr_kernel(void)
 {
     outb(0x4d0, 0);
@@ -315,7 +328,11 @@  static struct test tests[] = {
 #endif
 	{ inl_pmtimer, "inl_from_pmtimer", .parallel = 1, },
 	{ inl_nop_qemu, "inl_from_qemu", .parallel = 1 },
+	{ inl_nop_qemu, "inl_from_qemu (EFER guest = EFER host)", .parallel = 1,
+          .valid = set_sce, .after = clear_sce },
 	{ inl_nop_kernel, "inl_from_kernel", .parallel = 1 },
+	{ inl_nop_kernel, "inl_from_kernel (EFER guest = EFER host)", .parallel = 1,
+          .valid = set_sce, .after = clear_sce },
 	{ outl_elcr_kernel, "outl_to_kernel", .parallel = 1 },
 	{ mov_dr, "mov_dr", .parallel = 1 },
 	{ ipi, "ipi", is_smp, .parallel = 0, },
@@ -381,6 +398,9 @@  static bool do_test(struct test *test)
 		t2 = rdtsc();
 	} while ((t2 - t1) < GOAL);
 	printf("%s %d\n", test->name, (int)((t2 - t1) / iterations));
+	if (test->after) {
+		test->after();
+	}
 	return test->next;
 }