[PATCH v4 1/5] irq: add tracepoint to softirq_raise
From: Koki Sanagi <hidden>
Date: 2010-08-23 09:42:47
Also in:
lkml
Subsystem:
the rest, tracing · Maintainers:
Linus Torvalds, Steven Rostedt, Masami Hiramatsu
From: Lai Jiangshan <redacted> Add a tracepoint for tracing when softirq action is raised. It and the existed 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: Lai Jiangshan <redacted> Acked-by: Mathieu Desnoyers <redacted> Acked-by: Frederic Weisbecker <redacted> [ factorize softirq events with DECLARE_EVENT_CLASS ] Signed-off-by: Koki Sanagi <redacted> --- include/linux/interrupt.h | 8 +++++++- include/trace/events/irq.h | 26 ++++++++++++++++++++++++-- 2 files changed, 31 insertions(+), 3 deletions(-)
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index a0384a4..d3e8e90 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h@@ -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 *)&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);
diff --git a/include/trace/events/irq.h b/include/trace/events/irq.h
index 0e4cfb6..3ddda02 100644
--- a/include/trace/events/irq.h
+++ b/include/trace/events/irq.h@@ -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( - __entry->vec = (int)(h - vec); + if (vec) + __entry->vec = (int)(h - vec); + else + __entry->vec = *((int *)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 */