x86/fpu: Rename __fpregs_load_activate() to fpregs_restore_userregs()

Rename it so that it becomes entirely clear what this function is
about. It's purpose is to restore the FPU registers to the state which was
saved in the task's FPU memory state either at context switch or by an in
kernel FPU user.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20210623121456.018867925@linutronix.de

arch/x86/include/asm/fpu/internal.h

@@ -465,10 +465,8 @@ static inline void fpregs_activate(struct fpu *fpu)
 	trace_x86_fpu_regs_activated(fpu);
 }
 
-/*
- * Internal helper, do not use directly. Use switch_fpu_return() instead.
- */
-static inline void __fpregs_load_activate(void)
+/* Internal helper for switch_fpu_return() and signal frame setup */
+static inline void fpregs_restore_userregs(void)
 {
 	struct fpu *fpu = &current->thread.fpu;
 	int cpu = smp_processor_id();

arch/x86/kernel/fpu/core.c

@@ -402,7 +402,7 @@ void switch_fpu_return(void)
 	if (!static_cpu_has(X86_FEATURE_FPU))
 		return;
 
-	__fpregs_load_activate();
+	fpregs_restore_userregs();
 }
 EXPORT_SYMBOL_GPL(switch_fpu_return);
 

arch/x86/kernel/fpu/signal.c

@@ -188,7 +188,7 @@ int copy_fpstate_to_sigframe(void __user *buf, void __user *buf_fx, int size)
 	 */
 	fpregs_lock();
 	if (test_thread_flag(TIF_NEED_FPU_LOAD))
-		__fpregs_load_activate();
+		fpregs_restore_userregs();
 
 	pagefault_disable();
 	ret = copy_fpregs_to_sigframe(buf_fx);