x86: reduce preemption off section in exit thread

Impact: latency improvement

No need to keep preemption disabled over the kfree call.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 3 insertions, 2 deletions

diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 6afa5232dbb7..156f87582c6c 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -65,11 +65,11 @@ void exit_thread(void)
 {
         struct task_struct *me = current;
         struct thread_struct *t = &me->thread;
+        unsigned long *bp = t->io_bitmap_ptr;
 
-        if (me->thread.io_bitmap_ptr) {
+        if (bp) {
                 struct tss_struct *tss = &per_cpu(init_tss, get_cpu());
 
-                kfree(t->io_bitmap_ptr);
                 t->io_bitmap_ptr = NULL;
                 clear_thread_flag(TIF_IO_BITMAP);
                 /*
@@ -78,6 +78,7 @@ void exit_thread(void)
                 memset(tss->io_bitmap, 0xff, t->io_bitmap_max);
                 t->io_bitmap_max = 0;
                 put_cpu();
+                kfree(bp);
         }
 
         ds_exit_thread(current);