[patch V2 20/44] x86/irq_work: Make it depend on APIC

From: Thomas Gleixner
Date: Fri Aug 25 2017 - 18:05:38 EST


The irq work interrupt vector is only installed when CONFIG_X86_LOCAL_APIC is
enabled, but the interrupt handler is compiled in unconditionally.

Compile the cruft out when the APIC is disabled.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/include/asm/irq_work.h | 8 ++++++++
arch/x86/kernel/irq_work.c | 4 ++--
2 files changed, 10 insertions(+), 2 deletions(-)

--- a/arch/x86/include/asm/irq_work.h
+++ b/arch/x86/include/asm/irq_work.h
@@ -3,9 +3,17 @@

#include <asm/cpufeature.h>

+#ifdef CONFIG_X86_LOCAL_APIC
static inline bool arch_irq_work_has_interrupt(void)
{
return boot_cpu_has(X86_FEATURE_APIC);
}
+extern void arch_irq_work_raise(void);
+#else
+static inline bool arch_irq_work_has_interrupt(void)
+{
+ return false;
+}
+#endif

#endif /* _ASM_IRQ_WORK_H */
--- a/arch/x86/kernel/irq_work.c
+++ b/arch/x86/kernel/irq_work.c
@@ -11,6 +11,7 @@
#include <asm/trace/irq_vectors.h>
#include <linux/interrupt.h>

+#ifdef CONFIG_X86_LOCAL_APIC
__visible void __irq_entry smp_irq_work_interrupt(struct pt_regs *regs)
{
ipi_entering_ack_irq();
@@ -23,11 +24,10 @@

void arch_irq_work_raise(void)
{
-#ifdef CONFIG_X86_LOCAL_APIC
if (!arch_irq_work_has_interrupt())
return;

apic->send_IPI_self(IRQ_WORK_VECTOR);
apic_wait_icr_idle();
-#endif
}
+#endif