[PATCH v4 3/6] KVM: selftests: Move XGETBV and XSETBV helpers to common code

From: Sean Christopherson
Date: Tue Apr 04 2023 - 20:45:39 EST


From: Aaron Lewis <aaronlewis@xxxxxxxxxx>

The instructions XGETBV and XSETBV are useful to other tests. Move
them to processor.h to make them more broadly available.

No functional change intended.

Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
Signed-off-by: Aaron Lewis <aaronlewis@xxxxxxxxxx>
Reviewed-by: Mingwei Zhang <mizhang@xxxxxxxxxx>
[sean: reword shortlog]
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
.../selftests/kvm/include/x86_64/processor.h | 18 ++++++++++++++
tools/testing/selftests/kvm/x86_64/amx_test.c | 24 +++----------------
2 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index 3538fa6db72d..f6061fe7057f 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -510,6 +510,24 @@ static inline void set_cr4(uint64_t val)
__asm__ __volatile__("mov %0, %%cr4" : : "r" (val) : "memory");
}

+static inline u64 xgetbv(u32 index)
+{
+ u32 eax, edx;
+
+ __asm__ __volatile__("xgetbv;"
+ : "=a" (eax), "=d" (edx)
+ : "c" (index));
+ return eax | ((u64)edx << 32);
+}
+
+static inline void xsetbv(u32 index, u64 value)
+{
+ u32 eax = value;
+ u32 edx = value >> 32;
+
+ __asm__ __volatile__("xsetbv" :: "a" (eax), "d" (edx), "c" (index));
+}
+
static inline struct desc_ptr get_gdt(void)
{
struct desc_ptr gdt;
diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c
index 5c82d7e6f552..af1ef6f79d32 100644
--- a/tools/testing/selftests/kvm/x86_64/amx_test.c
+++ b/tools/testing/selftests/kvm/x86_64/amx_test.c
@@ -65,24 +65,6 @@ struct xtile_info {

static struct xtile_info xtile;

-static inline u64 __xgetbv(u32 index)
-{
- u32 eax, edx;
-
- asm volatile("xgetbv;"
- : "=a" (eax), "=d" (edx)
- : "c" (index));
- return eax + ((u64)edx << 32);
-}
-
-static inline void __xsetbv(u32 index, u64 value)
-{
- u32 eax = value;
- u32 edx = value >> 32;
-
- asm volatile("xsetbv" :: "a" (eax), "d" (edx), "c" (index));
-}
-
static inline void __ldtilecfg(void *cfg)
{
asm volatile(".byte 0xc4,0xe2,0x78,0x49,0x00"
@@ -160,10 +142,10 @@ static void init_regs(void)
set_cr4(cr4);
GUEST_ASSERT(this_cpu_has(X86_FEATURE_OSXSAVE));

- xcr0 = __xgetbv(0);
+ xcr0 = xgetbv(0);
xcr0 |= XFEATURE_MASK_XTILE;
- __xsetbv(0x0, xcr0);
- GUEST_ASSERT((__xgetbv(0) & XFEATURE_MASK_XTILE) == XFEATURE_MASK_XTILE);
+ xsetbv(0x0, xcr0);
+ GUEST_ASSERT((xgetbv(0) & XFEATURE_MASK_XTILE) == XFEATURE_MASK_XTILE);
}

static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg,
--
2.40.0.348.gf938b09366-goog