1 files changed, 24 insertions, 0 deletions

diff --git a/arch/x86/kernel/process.h b/arch/x86/kernel/process.h
new file mode 100644
index 000000000000..020fbfac3a27
--- /dev/null
+++ b/arch/x86/kernel/process.h
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Code shared between 32 and 64 bit
+
+void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p);
+
+/*
+ * This needs to be inline to optimize for the common case where no extra
+ * work needs to be done.
+ */
+static inline void switch_to_extra(struct task_struct *prev,
+                                   struct task_struct *next)
+{
+        unsigned long next_tif = task_thread_info(next)->flags;
+        unsigned long prev_tif = task_thread_info(prev)->flags;
+
+        /*
+         * __switch_to_xtra() handles debug registers, i/o bitmaps,
+         * speculation mitigations etc.
+         */
+        if (unlikely(next_tif & _TIF_WORK_CTXSW_NEXT ||
+                     prev_tif & _TIF_WORK_CTXSW_PREV))
+                __switch_to_xtra(prev, next);
+}