Commit 2bf2160d authored by Lai Jiangshan's avatar Lai Jiangshan Committed by Frederic Weisbecker
Browse files

irq: Add tracepoint to softirq_raise 



Add a tracepoint for tracing when softirq action is raised.

This and the existing tracepoints complete softirq's tracepoints:
softirq_raise, softirq_entry and softirq_exit.

And when this tracepoint is used in combination with
the softirq_entry tracepoint we can determine
the softirq raise latency.

Signed-off-by: default avatarLai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: default avatarMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
Cc: David Miller <davem@davemloft.net>
Cc: Kaneshige Kenji <kaneshige.kenji@jp.fujitsu.com>
Cc: Izumo Taku <izumi.taku@jp.fujitsu.com>
Cc: Kosaki Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Scott Mcmillan <scott.a.mcmillan@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
LKML-Reference: <4C724298.4050509@jp.fujitsu.com>
[ factorize softirq events with DECLARE_EVENT_CLASS ]
Signed-off-by: default avatarKoki Sanagi <sanagi.koki@jp.fujitsu.com>
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
parent f6195aa0

include/linux/interrupt.h

+7 −1
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include <asm/atomic.h>

#include <asm/ptrace.h>

#include <asm/system.h>

#include <trace/events/irq.h>



/*

 * These correspond to the IORESOURCE_IRQ_* defines in
@@ -407,7 +408,12 @@ asmlinkage void do_softirq(void); 
asmlinkage void __do_softirq(void);

extern void open_softirq(int nr, void (*action)(struct softirq_action *));

extern void softirq_init(void);

#define __raise_softirq_irqoff(nr) do { or_softirq_pending(1UL << (nr)); } while (0)

static inline void __raise_softirq_irqoff(unsigned int nr)

{

	trace_softirq_raise((struct softirq_action *)(unsigned long)nr, NULL);

	or_softirq_pending(1UL << nr);

}



extern void raise_softirq_irqoff(unsigned int nr);

extern void raise_softirq(unsigned int nr);

extern void wakeup_softirqd(void);

include/trace/events/irq.h

+24 −2
Original line number Diff line number Diff line
@@ -5,7 +5,9 @@ 
#define _TRACE_IRQ_H



#include <linux/tracepoint.h>

#include <linux/interrupt.h>



struct irqaction;

struct softirq_action;



#define softirq_name(sirq) { sirq##_SOFTIRQ, #sirq }

#define show_softirq_name(val)				\
@@ -93,7 +95,10 @@ DECLARE_EVENT_CLASS(softirq, 
	),



	TP_fast_assign(

		if (vec)

			__entry->vec = (int)(h - vec);

		else

			__entry->vec = (int)(long)h;

	),



	TP_printk("vec=%d [action=%s]", __entry->vec,
@@ -136,6 +141,23 @@ DEFINE_EVENT(softirq, softirq_exit, 
	TP_ARGS(h, vec)

);



/**

 * softirq_raise - called immediately when a softirq is raised

 * @h: pointer to struct softirq_action

 * @vec: pointer to first struct softirq_action in softirq_vec array

 *

 * The @h parameter contains a pointer to the softirq vector number which is

 * raised. @vec is NULL and it means @h includes vector number not

 * softirq_action. When used in combination with the softirq_entry tracepoint

 * we can determine the softirq raise latency.

 */

DEFINE_EVENT(softirq, softirq_raise,



	TP_PROTO(struct softirq_action *h, struct softirq_action *vec),



	TP_ARGS(h, vec)

);



#endif /*  _TRACE_IRQ_H */



/* This part must be outside protection */

CRA Git | Maintained and supported by SUSTech CRA and CCSE