[patch 04/12] x86/apic: Split out spurious handling code

Thomas Gleixner
2021-02-05T00:59:32Z

sysvec_spurious_apic_interrupt() calls into the handling body of
__spurious_interrupt() which is not obvious as that function is declared
inside the DEFINE_IDTENTRY_IRQ(spurious_interrupt) macro.

As __spurious_interrupt() is currently always inlined this ends up with two
copies of the same code for no reason.

Split the handling function out and invoke it from both entry points.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/kernel/apic/apic.c | 31 +++++++++++++++++++------------
1 file changed, 19 insertions(+), 12 deletions(-)

--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2133,18 +2133,11 @@ void __init register_lapic_address(unsig
* Local APIC interrupts
*/

-/**
- * spurious_interrupt - Catch all for interrupts raised on unused vectors
- * @regs: Pointer to pt_regs on stack
- * @vector: The vector number
- *
- * This is invoked from ASM entry code to catch all interrupts which
- * trigger on an entry which is routed to the common_spurious idtentry
- * point.
- *
- * Also called from sysvec_spurious_apic_interrupt().
+/*
+ * Common handling code for spurious_interrupt and spurious_vector entry
+ * points below. No point in allowing the compiler to inline it twice.
*/
-DEFINE_IDTENTRY_IRQ(spurious_interrupt)
+static noinline void handle_spurious_interrupt(u8 vector)
{
u32 v;

@@ -2179,9 +2172,23 @@ DEFINE_IDTENTRY_IRQ(spurious_interrupt)
trace_spurious_apic_exit(vector);
}

+/**
+ * spurious_interrupt - Catch all for interrupts raised on unused vectors
+ * @regs: Pointer to pt_regs on stack
+ * @vector: The vector number
+ *
+ * This is invoked from ASM entry code to catch all interrupts which
+ * trigger on an entry which is routed to the common_spurious idtentry
+ * point.
+ */
+DEFINE_IDTENTRY_IRQ(spurious_interrupt)
+{
+ handle_spurious_interrupt(vector);
+}
+
DEFINE_IDTENTRY_SYSVEC(sysvec_spurious_apic_interrupt)
{
- __spurious_interrupt(regs, SPURIOUS_APIC_VECTOR);
+ handle_spurious_interrupt(SPURIOUS_APIC_VECTOR);
}

/*