irq.h File Reference

#include <linux/tracepoint.h>
#include <trace/define_trace.h>

Go to the source code of this file.

Macros
#define	TRACE_SYSTEM   irq
#define	_TRACE_IRQ_H
#define	softirq_name(sirq)   { sirq##_SOFTIRQ, #sirq }
#define	show_softirq_name(val)

Functions
	TRACE_EVENT (irq_handler_entry, TP_PROTO(int irq, struct irqaction *action), TP_ARGS(irq, action), TP_STRUCT__entry(__field(int, irq) __string(name, action->name)), TP_fast_assign(__entry->irq=irq;__assign_str(name, action->name);), TP_printk("irq=%d name=%s", __entry->irq, __get_str(name)))
	TRACE_EVENT (irq_handler_exit, TP_PROTO(int irq, struct irqaction *action, int ret), TP_ARGS(irq, action, ret), TP_STRUCT__entry(__field(int, irq) __field(int, ret)), TP_fast_assign(__entry->irq=irq;__entry->ret=ret;), TP_printk("irq=%d ret=%s", __entry->irq, __entry->ret?"handled":"unhandled"))
	DECLARE_EVENT_CLASS (softirq, TP_PROTO(unsigned int vec_nr), TP_ARGS(vec_nr), TP_STRUCT__entry(__field(unsigned int, vec)), TP_fast_assign(__entry->vec=vec_nr;), TP_printk("vec=%u [action=%s]", __entry->vec, show_softirq_name(__entry->vec)))
	DEFINE_EVENT (softirq, softirq_entry, TP_PROTO(unsigned int vec_nr),)
	DEFINE_EVENT (softirq, softirq_exit, TP_PROTO(unsigned int vec_nr),)
	DEFINE_EVENT (softirq, softirq_raise, TP_PROTO(unsigned int vec_nr),)

Macro Definition Documentation

#define _TRACE_IRQ_H

Definition at line 5 of file irq.h.

#define show_softirq_name

(

val

)

Value:

__print_symbolic(val,               \
             softirq_name(HI),      \
             softirq_name(TIMER),       \
             softirq_name(NET_TX),      \
             softirq_name(NET_RX),      \
             softirq_name(BLOCK),       \
             softirq_name(BLOCK_IOPOLL),    \
             softirq_name(TASKLET),     \
             softirq_name(SCHED),       \
             softirq_name(HRTIMER),     \
             softirq_name(RCU))

Definition at line 13 of file irq.h.

#define softirq_name

(

sirq

)

{ sirq##_SOFTIRQ, #sirq }

Definition at line 12 of file irq.h.

#define TRACE_SYSTEM   irq

Definition at line 2 of file irq.h.

Function Documentation

DECLARE_EVENT_CLASS	(	softirq	,
		TP_PROTO(unsigned int vec_nr)	,
		TP_ARGS(vec_nr)	,
		TP_STRUCT__entry(__field(unsigned int, vec))	,
		TP_fast_assign(__entry->vec=vec_nr;)	,
		TP_printk("vec=%u [action=%s]", __entry->vec, show_softirq_name(__entry->vec))
	)

DEFINE_EVENT	(	softirq	,
		softirq_entry	,
		TP_PROTO(unsigned int vec_nr)
	)

softirq_entry - called immediately before the softirq handler : softirq vector number

When used in combination with the softirq_exit tracepoint we can determine the softirq handler runtine.

DEFINE_EVENT	(	softirq	,
		softirq_exit	,
		TP_PROTO(unsigned int vec_nr)
	)

softirq_exit - called immediately after the softirq handler returns : softirq vector number

When used in combination with the softirq_entry tracepoint we can determine the softirq handler runtine.

DEFINE_EVENT	(	softirq	,
		softirq_raise	,
		TP_PROTO(unsigned int vec_nr)
	)

softirq_raise - called immediately when a softirq is raised : softirq vector number

When used in combination with the softirq_entry tracepoint we can determine the softirq raise to run latency.

TRACE_EVENT	(	irq_handler_entry	,
		TP_PROTO(int irq, struct irqaction *action)	,
		TP_ARGS(irq, action)	,
		TP_STRUCT__entry(__field(int, irq) __string(name, action->name))	,
		TP_fast_assign(__entry->irq=irq;__assign_str(name, action->name);)	,
		TP_printk("irq=%d name=%s", __entry->irq, __get_str(name))
	)

irq_handler_entry - called immediately before the irq action handler : irq number : pointer to struct irqaction

The struct irqaction pointed to by contains various information about the handler, including the device name, ->name, and the device id, ->dev_id. When used in conjunction with the irq_handler_exit tracepoint, we can figure out irq handler latencies.

TRACE_EVENT	(	irq_handler_exit	,
		TP_PROTO(int irq, struct irqaction *action, int ret)	,
		TP_ARGS(irq, action, ret)	,
		TP_STRUCT__entry(__field(int, irq) __field(int, ret))	,
		TP_fast_assign(__entry->irq=irq;__entry->ret=ret;)	,
		TP_printk("irq=%d ret=%s", __entry->irq, __entry->ret?"handled":"unhandled")
	)

irq_handler_exit - called immediately after the irq action handler returns : irq number : pointer to struct irqaction : return value

If the value is set to IRQ_HANDLED, then we know that the corresponding ->handler scuccessully handled this irq. Otherwise, the irq might be a shared irq line, or the irq was not handled successfully. Can be used in conjunction with the irq_handler_entry to understand irq handler latencies.