KVM: selftests: Better XMM read/write helpers

set_xmm()/get_xmm() helpers are fairly useless as they only read 64 bits
from 128-bit registers. Moreover, these helpers are not used. Borrow
_kvm_read_sse_reg()/_kvm_write_sse_reg() from KVM limiting them to
XMM0-XMM8 for now.

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20221101145426.251680-31-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index f838ac5865dc59ec6fa3f7d6ff69b18a1e1bb105..a10f39affa45e498357b126f5fc9cbc7bca1346e 100644 (file)
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -603,71 +603,73 @@ static inline bool this_pmu_has(struct kvm_x86_pmu_feature feature)
               !this_cpu_has(feature.anti_feature);
 }
 
-#define SET_XMM(__var, __xmm) \
-       asm volatile("movq %0, %%"#__xmm : : "r"(__var) : #__xmm)
+typedef u32            __attribute__((vector_size(16))) sse128_t;
+#define __sse128_u     union { sse128_t vec; u64 as_u64[2]; u32 as_u32[4]; }
+#define sse128_lo(x)   ({ __sse128_u t; t.vec = x; t.as_u64[0]; })
+#define sse128_hi(x)   ({ __sse128_u t; t.vec = x; t.as_u64[1]; })
 
-static inline void set_xmm(int n, unsigned long val)
+static inline void read_sse_reg(int reg, sse128_t *data)
 {
-       switch (n) {
+       switch (reg) {
        case 0:
-               SET_XMM(val, xmm0);
+               asm("movdqa %%xmm0, %0" : "=m"(*data));
                break;
        case 1:
-               SET_XMM(val, xmm1);
+               asm("movdqa %%xmm1, %0" : "=m"(*data));
                break;
        case 2:
-               SET_XMM(val, xmm2);
+               asm("movdqa %%xmm2, %0" : "=m"(*data));
                break;
        case 3:
-               SET_XMM(val, xmm3);
+               asm("movdqa %%xmm3, %0" : "=m"(*data));
                break;
        case 4:
-               SET_XMM(val, xmm4);
+               asm("movdqa %%xmm4, %0" : "=m"(*data));
                break;
        case 5:
-               SET_XMM(val, xmm5);
+               asm("movdqa %%xmm5, %0" : "=m"(*data));
                break;
        case 6:
-               SET_XMM(val, xmm6);
+               asm("movdqa %%xmm6, %0" : "=m"(*data));
                break;
        case 7:
-               SET_XMM(val, xmm7);
+               asm("movdqa %%xmm7, %0" : "=m"(*data));
                break;
+       default:
+               BUG();
        }
 }
 
-#define GET_XMM(__xmm)                                                 \
-({                                                                     \
-       unsigned long __val;                                            \
-       asm volatile("movq %%"#__xmm", %0" : "=r"(__val));              \
-       __val;                                                          \
-})
-
-static inline unsigned long get_xmm(int n)
+static inline void write_sse_reg(int reg, const sse128_t *data)
 {
-       assert(n >= 0 && n <= 7);
-
-       switch (n) {
+       switch (reg) {
        case 0:
-               return GET_XMM(xmm0);
+               asm("movdqa %0, %%xmm0" : : "m"(*data));
+               break;
        case 1:
-               return GET_XMM(xmm1);
+               asm("movdqa %0, %%xmm1" : : "m"(*data));
+               break;
        case 2:
-               return GET_XMM(xmm2);
+               asm("movdqa %0, %%xmm2" : : "m"(*data));
+               break;
        case 3:
-               return GET_XMM(xmm3);
+               asm("movdqa %0, %%xmm3" : : "m"(*data));
+               break;
        case 4:
-               return GET_XMM(xmm4);
+               asm("movdqa %0, %%xmm4" : : "m"(*data));
+               break;
        case 5:
-               return GET_XMM(xmm5);
+               asm("movdqa %0, %%xmm5" : : "m"(*data));
+               break;
        case 6:
-               return GET_XMM(xmm6);
+               asm("movdqa %0, %%xmm6" : : "m"(*data));
+               break;
        case 7:
-               return GET_XMM(xmm7);
+               asm("movdqa %0, %%xmm7" : : "m"(*data));
+               break;
+       default:
+               BUG();
        }
-
-       /* never reached */
-       return 0;
 }
 
 static inline void cpu_relax(void)