[PATCH 1/2] trace,x86: Add external_interrupts to the irq_vectors class

From: Daniel Bristot de Oliveira
Date: Mon Sep 17 2018 - 04:49:01 EST


Currently, the irq_vectors is showing the entry and exit events for
the interrupts of the architecture, but not for external interrupts.
This patch adds the tracepoints for external interrupts.

Example of output:
<idle>-0 [000] d.h. 102.890935: external_interrupt_entry: vector=35
<idle>-0 [000] d.h. 102.890960: external_interrupt_exit: vector=35

Signed-off-by: Daniel Bristot de Oliveira <bristot@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Clark Williams <williams@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: x86@xxxxxxxxxx
---
arch/x86/include/asm/trace/irq_vectors.h | 6 ++++++
arch/x86/kernel/irq.c | 2 ++
2 files changed, 8 insertions(+)

diff --git a/arch/x86/include/asm/trace/irq_vectors.h b/arch/x86/include/asm/trace/irq_vectors.h
index 0af81b590a0c..bc9669df97c9 100644
--- a/arch/x86/include/asm/trace/irq_vectors.h
+++ b/arch/x86/include/asm/trace/irq_vectors.h
@@ -138,6 +138,12 @@ DEFINE_IRQ_VECTOR_EVENT(deferred_error_apic);
DEFINE_IRQ_VECTOR_EVENT(thermal_apic);
#endif

+/*
+ * external_interrupt - called when entering/exiting from regular device
+ * interrupt vector handler.
+ */
+DEFINE_IRQ_VECTOR_EVENT(external_interrupt);
+
TRACE_EVENT(vector_config,

TP_PROTO(unsigned int irq, unsigned int vector,
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 59b5f2ea7c2f..715afe3a4f24 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -237,6 +237,7 @@ __visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
unsigned vector = ~regs->orig_ax;

entering_irq();
+ trace_external_interrupt_entry(vector);

/* entering_irq() tells RCU that we're not quiescent. Check it. */
RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
@@ -255,6 +256,7 @@ __visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
}
}

+ trace_external_interrupt_exit(vector);
exiting_irq();

set_irq_regs(old_regs);
--
2.17.1