[patch V3 14/44] x86/smp: Remove pointless duplicated interrupt code

Thomas Gleixner
2017-08-28T07:02:11Z

[-- Attachment #1: x86-smp--Remove-pointless-duplicated-interrupt-code.patch --]
[-- Type: text/plain, Size: 3088 bytes --]

Two NOP5 are really a good tradeoff vs. the unholy IDT switching mess,
which duplicates code all over the place. The rescheduling interrupt gets
optimized in a later step.

Make the ordering of function call and statistics increment the same as in
other places. stats first, then function call.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/include/asm/hw_irq.h | 4 +--
arch/x86/kernel/smp.c | 43 ++++++------------------------------------
2 files changed, 9 insertions(+), 38 deletions(-)

--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -49,8 +49,8 @@ extern asmlinkage void call_function_sin
#ifdef CONFIG_TRACING
/* Interrupt handlers registered during init_IRQ */
extern void trace_reschedule_interrupt(void);
-extern void trace_call_function_interrupt(void);
-extern void trace_call_function_single_interrupt(void);
+#define trace_call_function_interrupt call_function_interrupt
+#define trace_call_function_single_interrupt call_function_single_interrupt
#define trace_thermal_interrupt thermal_interrupt
#define trace_threshold_interrupt threshold_interrupt
#define trace_deferred_error_interrupt deferred_error_interrupt
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -281,57 +281,28 @@ static inline void __smp_reschedule_inte
*/
ipi_entering_ack_irq();
trace_reschedule_entry(RESCHEDULE_VECTOR);
- __smp_reschedule_interrupt();
+ inc_irq_stat(irq_resched_count);
+ scheduler_ipi();
trace_reschedule_exit(RESCHEDULE_VECTOR);
exiting_irq();
- /*
- * KVM uses this interrupt to force a cpu out of guest mode
- */
-}
-
-static inline void __smp_call_function_interrupt(void)
-{
- generic_smp_call_function_interrupt();
- inc_irq_stat(irq_call_count);
}

__visible void __irq_entry smp_call_function_interrupt(struct pt_regs *regs)
{
ipi_entering_ack_irq();
- __smp_call_function_interrupt();
- exiting_irq();
-}
-
-__visible void __irq_entry
-smp_trace_call_function_interrupt(struct pt_regs *regs)
-{
- ipi_entering_ack_irq();
trace_call_function_entry(CALL_FUNCTION_VECTOR);
- __smp_call_function_interrupt();
- trace_call_function_exit(CALL_FUNCTION_VECTOR);
- exiting_irq();
-}
-
-static inline void __smp_call_function_single_interrupt(void)
-{
- generic_smp_call_function_single_interrupt();
inc_irq_stat(irq_call_count);
-}
-
-__visible void __irq_entry
-smp_call_function_single_interrupt(struct pt_regs *regs)
-{
- ipi_entering_ack_irq();
- __smp_call_function_single_interrupt();
+ generic_smp_call_function_interrupt();
+ trace_call_function_exit(CALL_FUNCTION_VECTOR);
exiting_irq();
}

-__visible void __irq_entry
-smp_trace_call_function_single_interrupt(struct pt_regs *regs)
+__visible void __irq_entry smp_call_function_single_interrupt(struct pt_regs *r)
{
ipi_entering_ack_irq();
trace_call_function_single_entry(CALL_FUNCTION_SINGLE_VECTOR);
- __smp_call_function_single_interrupt();
+ inc_irq_stat(irq_call_count);
+ generic_smp_call_function_single_interrupt();
trace_call_function_single_exit(CALL_FUNCTION_SINGLE_VECTOR);
exiting_irq();
}