traps: x86_64: make math_state_restore more like i386

- rename variable me -> tsk
 - get thread and tsk like i386
 - expand used_math()
 - copy comment

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 8 insertions, 7 deletions

diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c
index ea091dfe0cd3..00406c99aee4 100644
--- a/arch/x86/kernel/traps_64.c
+++ b/arch/x86/kernel/traps_64.c
@@ -604,14 +604,15 @@ asmlinkage void __attribute__((weak)) mce_threshold_interrupt(void)
  */
 asmlinkage void math_state_restore(void)
 {
-        struct task_struct *me = current;
+        struct thread_info *thread = current_thread_info();
+        struct task_struct *tsk = thread->task;
 
-        if (!used_math()) {
+        if (!tsk_used_math(tsk)) {
                 local_irq_enable();
                 /*
                  * does a slab alloc which can sleep
                  */
-                if (init_fpu(me)) {
+                if (init_fpu(tsk)) {
                         /*
                          * ran out of memory!
                          */
@@ -625,13 +626,13 @@ asmlinkage void math_state_restore(void)
         /*
          * Paranoid restore. send a SIGSEGV if we fail to restore the state.
          */
-        if (unlikely(restore_fpu_checking(me))) {
+        if (unlikely(restore_fpu_checking(tsk))) {
                 stts();
-                force_sig(SIGSEGV, me);
+                force_sig(SIGSEGV, tsk);
                 return;
         }
-        task_thread_info(me)->status |= TS_USEDFPU;
-        me->fpu_counter++;
+        thread->status |= TS_USEDFPU;   /* So we fnsave on switch_to() */
+        tsk->fpu_counter++;
 }
 EXPORT_SYMBOL_GPL(math_state_restore);