[patch V4 part 5 04/31] x86/entry: Split idtentry_enter/exit()

Thomas Gleixner
2020-05-05T14:18:49Z

Split the implementation of idtentry_enter/exit() out into inline functions
so that variaants of idtentry_enter/exit() can be implemented without
duplicating code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/entry/common.c | 37 +++++++++++++++++++++----------------
1 file changed, 21 insertions(+), 16 deletions(-)

--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -539,22 +539,7 @@ void noinstr idtentry_enter(struct pt_re
}
}

-/**
- * idtentry_exit - Common code to handle return from exceptions
- * @regs: Pointer to pt_regs (exception entry regs)
- *
- * Depending on the return target (kernel/user) this runs the necessary
- * preemption and work checks if possible and reguired and returns to
- * the caller with interrupts disabled and no further work pending.
- *
- * This is the last action before returning to the low level ASM code which
- * just needs to return to the appropriate context.
- *
- * Invoked by all exception/interrupt IDTENTRY handlers which are not
- * returning through the paranoid exit path (all except NMI, #DF and the IST
- * variants of #MC and #DB).
- */
-void noinstr idtentry_exit(struct pt_regs *regs)
+static __always_inline void __idtentry_exit(struct pt_regs *regs)
{
lockdep_assert_irqs_disabled();

@@ -599,3 +584,23 @@ void noinstr idtentry_exit(struct pt_reg
rcu_irq_exit();
}
}
+
+/**
+ * idtentry_exit - Common code to handle return from exceptions
+ * @regs: Pointer to pt_regs (exception entry regs)
+ *
+ * Depending on the return target (kernel/user) this runs the necessary
+ * preemption and work checks if possible and reguired and returns to
+ * the caller with interrupts disabled and no further work pending.
+ *
+ * This is the last action before returning to the low level ASM code which
+ * just needs to return to the appropriate context.
+ *
+ * Invoked by all exception/interrupt IDTENTRY handlers which are not
+ * returning through the paranoid exit path (all except NMI, #DF and the IST
+ * variants of #MC and #DB).
+ */
+void noinstr idtentry_exit(struct pt_regs *regs)
+{
+ __idtentry_exit(regs);
+}