[PATCH 5/5] KVM: x86: kvm_fpu_get() is fpregs_lock_and_load()

[Paolo Bonzini]

The only difference is the usage of switch_fpu_return() vs.
fpregs_restore_userregs().  In turn, these are only different
if there is no FPU at all, but KVM requires one.  Therefore use the
pre-made export---the code is simpler and there is no functional change.

Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
 arch/x86/kernel/fpu/core.c | 2 +--
 arch/x86/kvm/fpu.h         | 6 +-----
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index ff17c96d290a..6571952c6ef1 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -846,7 +846,6 @@ void switch_fpu_return(void)
 
 	fpregs_restore_userregs();
 }
-EXPORT_SYMBOL_FOR_KVM(switch_fpu_return);
 
 void fpregs_lock_and_load(void)
 {
@@ -865,6 +864,7 @@ void fpregs_lock_and_load(void)
 
 	fpregs_assert_state_consistent();
 }
+EXPORT_SYMBOL_FOR_KVM(fpregs_lock_and_load);
 
 void fpu_load_guest_fpstate(struct fpu_guest *gfpu)
 {
@@ -899,7 +899,6 @@ void fpregs_assert_state_consistent(void)
 
 	WARN_ON_FPU(!fpregs_state_valid(fpu, smp_processor_id()));
 }
-EXPORT_SYMBOL_FOR_KVM(fpregs_assert_state_consistent);
 #endif
 
 void fpregs_mark_activate(void)
diff --git a/arch/x86/kvm/fpu.h b/arch/x86/kvm/fpu.h
index f898781b6a06..b6a03d8fa8af 100644
--- a/arch/x86/kvm/fpu.h
+++ b/arch/x86/kvm/fpu.h
@@ -149,11 +149,7 @@ static inline void _kvm_write_mmx_reg(int reg, const u64 *data)
 
 static inline void kvm_fpu_get(void)
 {
-	fpregs_lock();
-
-	fpregs_assert_state_consistent();
-	if (test_thread_flag(TIF_NEED_FPU_LOAD))
-		switch_fpu_return();
+	fpregs_lock_and_load();
 }
 
 static inline void kvm_fpu_put(void)
-- 
2.52.0