[patch V5 28/38] x86/entry: Convert KVM vectors to IDTENTRY_SYSVEC

Thomas Gleixner
2020-05-12T22:25:26Z

From: Thomas Gleixner <tglx@linutronix.de>

Convert KVM specific system vectors to IDTENTRY_SYSVEC*:

The two empty stub handlers which only increment the stats counter do no
need to run on the interrupt stack. Use IDTENTRY_SYSVEC_DIRECT for them.

The wakeup handler does more work and runs on the interrupt stack.

None of these handlers need to save and restore the irq_regs pointer.

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

---
arch/x86/entry/entry_64.S | 7 -------
arch/x86/include/asm/entry_arch.h | 7 -------
arch/x86/include/asm/hw_irq.h | 4 ----
arch/x86/include/asm/idtentry.h | 6 ++++++
arch/x86/include/asm/irq.h | 3 ---
arch/x86/kernel/idt.c | 6 +++---
arch/x86/kernel/irq.c | 24 ++++++------------------
7 files changed, 15 insertions(+), 42 deletions(-)

--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -956,13 +956,6 @@ apicinterrupt3 \num \sym \do_sym
POP_SECTION_IRQENTRY
.endm

-
-#ifdef CONFIG_HAVE_KVM
-apicinterrupt3 POSTED_INTR_VECTOR kvm_posted_intr_ipi smp_kvm_posted_intr_ipi
-apicinterrupt3 POSTED_INTR_WAKEUP_VECTOR kvm_posted_intr_wakeup_ipi smp_kvm_posted_intr_wakeup_ipi
-apicinterrupt3 POSTED_INTR_NESTED_VECTOR kvm_posted_intr_nested_ipi smp_kvm_posted_intr_nested_ipi
-#endif
-
#ifdef CONFIG_SMP
apicinterrupt RESCHEDULE_VECTOR reschedule_interrupt smp_reschedule_interrupt
#endif
--- a/arch/x86/include/asm/entry_arch.h
+++ b/arch/x86/include/asm/entry_arch.h
@@ -13,10 +13,3 @@
#ifdef CONFIG_SMP
BUILD_INTERRUPT(reschedule_interrupt,RESCHEDULE_VECTOR)
#endif
-
-#ifdef CONFIG_HAVE_KVM
-BUILD_INTERRUPT(kvm_posted_intr_ipi, POSTED_INTR_VECTOR)
-BUILD_INTERRUPT(kvm_posted_intr_wakeup_ipi, POSTED_INTR_WAKEUP_VECTOR)
-BUILD_INTERRUPT(kvm_posted_intr_nested_ipi, POSTED_INTR_NESTED_VECTOR)
-#endif
-
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -29,10 +29,6 @@
#include <asm/sections.h>

/* Interrupt handlers registered during init_IRQ */
-extern asmlinkage void kvm_posted_intr_ipi(void);
-extern asmlinkage void kvm_posted_intr_wakeup_ipi(void);
-extern asmlinkage void kvm_posted_intr_nested_ipi(void);
-
extern asmlinkage void reschedule_interrupt(void);

#ifdef CONFIG_X86_LOCAL_APIC
--- a/arch/x86/include/asm/idtentry.h
+++ b/arch/x86/include/asm/idtentry.h
@@ -604,6 +604,12 @@ DECLARE_IDTENTRY_SYSVEC(IRQ_WORK_VECTOR,
# endif
#endif

+#ifdef CONFIG_HAVE_KVM
+DECLARE_IDTENTRY_SYSVEC(POSTED_INTR_VECTOR, sysvec_kvm_posted_intr_ipi);
+DECLARE_IDTENTRY_SYSVEC(POSTED_INTR_WAKEUP_VECTOR, sysvec_kvm_posted_intr_wakeup_ipi);
+DECLARE_IDTENTRY_SYSVEC(POSTED_INTR_NESTED_VECTOR, sysvec_kvm_posted_intr_nested_ipi);
+#endif
+
#undef X86_TRAP_OTHER

#endif
--- a/arch/x86/include/asm/irq.h
+++ b/arch/x86/include/asm/irq.h
@@ -26,9 +26,6 @@ extern void fixup_irqs(void);

#ifdef CONFIG_HAVE_KVM
extern void kvm_set_posted_intr_wakeup_handler(void (*handler)(void));
-extern __visible void smp_kvm_posted_intr_ipi(struct pt_regs *regs);
-extern __visible void smp_kvm_posted_intr_wakeup_ipi(struct pt_regs *regs);
-extern __visible void smp_kvm_posted_intr_nested_ipi(struct pt_regs *regs);
#endif

extern void (*x86_platform_ipi_callback)(void);
--- a/arch/x86/kernel/idt.c
+++ b/arch/x86/kernel/idt.c
@@ -132,9 +132,9 @@ static const __initconst struct idt_data
INTG(LOCAL_TIMER_VECTOR, asm_sysvec_apic_timer_interrupt),
INTG(X86_PLATFORM_IPI_VECTOR, asm_sysvec_x86_platform_ipi),
# ifdef CONFIG_HAVE_KVM
- INTG(POSTED_INTR_VECTOR, kvm_posted_intr_ipi),
- INTG(POSTED_INTR_WAKEUP_VECTOR, kvm_posted_intr_wakeup_ipi),
- INTG(POSTED_INTR_NESTED_VECTOR, kvm_posted_intr_nested_ipi),
+ INTG(POSTED_INTR_VECTOR, asm_sysvec_kvm_posted_intr_ipi),
+ INTG(POSTED_INTR_WAKEUP_VECTOR, asm_sysvec_kvm_posted_intr_wakeup_ipi),
+ INTG(POSTED_INTR_NESTED_VECTOR, asm_sysvec_kvm_posted_intr_nested_ipi),
# endif
# ifdef CONFIG_IRQ_WORK
INTG(IRQ_WORK_VECTOR, asm_sysvec_irq_work),
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -290,41 +290,29 @@ EXPORT_SYMBOL_GPL(kvm_set_posted_intr_wa
/*
* Handler for POSTED_INTERRUPT_VECTOR.
*/
-__visible void smp_kvm_posted_intr_ipi(struct pt_regs *regs)
+DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_kvm_posted_intr_ipi)
{
- struct pt_regs *old_regs = set_irq_regs(regs);
-
- entering_ack_irq();
+ ack_APIC_irq();
inc_irq_stat(kvm_posted_intr_ipis);
- exiting_irq();
- set_irq_regs(old_regs);
}

/*
* Handler for POSTED_INTERRUPT_WAKEUP_VECTOR.
*/
-__visible void smp_kvm_posted_intr_wakeup_ipi(struct pt_regs *regs)
+DEFINE_IDTENTRY_SYSVEC(sysvec_kvm_posted_intr_wakeup_ipi)
{
- struct pt_regs *old_regs = set_irq_regs(regs);
-
- entering_ack_irq();
+ ack_APIC_irq();
inc_irq_stat(kvm_posted_intr_wakeup_ipis);
kvm_posted_intr_wakeup_handler();
- exiting_irq();
- set_irq_regs(old_regs);
}

/*
* Handler for POSTED_INTERRUPT_NESTED_VECTOR.
*/
-__visible void smp_kvm_posted_intr_nested_ipi(struct pt_regs *regs)
+DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_kvm_posted_intr_nested_ipi)
{
- struct pt_regs *old_regs = set_irq_regs(regs);
-
- entering_ack_irq();
+ ack_APIC_irq();
inc_irq_stat(kvm_posted_intr_nested_ipis);
- exiting_irq();
- set_irq_regs(old_regs);
}
#endif