From e36c886a0f9d624377977fa6cae309cfd7f362fa Mon Sep 17 00:00:00 2001 From: Arjan van de Ven Date: Sat, 21 Aug 2010 13:07:26 -0700 Subject: workqueue: Add basic tracepoints to track workqueue execution With the introduction of the new unified work queue thread pools, we lost one feature: It's no longer possible to know which worker is causing the CPU to wake out of idle. The result is that PowerTOP now reports a lot of "kworker/a:b" instead of more readable results. This patch adds a pair of tracepoints to the new workqueue code, similar in style to the timer/hrtimer tracepoints. With this pair of tracepoints, the next PowerTOP can correctly report which work item caused the wakeup (and how long it took): Interrupt (43) i915 time 3.51ms wakeups 141 Work ieee80211_iface_work time 0.81ms wakeups 29 Work do_dbs_timer time 0.55ms wakeups 24 Process Xorg time 21.36ms wakeups 4 Timer sched_rt_period_timer time 0.01ms wakeups 1 Signed-off-by: Arjan van de Ven Signed-off-by: Linus Torvalds --- include/trace/events/workqueue.h | 62 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 62 insertions(+) create mode 100644 include/trace/events/workqueue.h (limited to 'include') diff --git a/include/trace/events/workqueue.h b/include/trace/events/workqueue.h new file mode 100644 index 000000000000..49682d7e9d60 --- /dev/null +++ b/include/trace/events/workqueue.h @@ -0,0 +1,62 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM workqueue + +#if !defined(_TRACE_WORKQUEUE_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_WORKQUEUE_H + +#include +#include + +/** + * workqueue_execute_start - called immediately before the workqueue callback + * @work: pointer to struct work_struct + * + * Allows to track workqueue execution. + */ +TRACE_EVENT(workqueue_execute_start, + + TP_PROTO(struct work_struct *work), + + TP_ARGS(work), + + TP_STRUCT__entry( + __field( void *, work ) + __field( void *, function) + ), + + TP_fast_assign( + __entry->work = work; + __entry->function = work->func; + ), + + TP_printk("work struct %p: function %pf", __entry->work, __entry->function) +); + +/** + * workqueue_execute_end - called immediately before the workqueue callback + * @work: pointer to struct work_struct + * + * Allows to track workqueue execution. + */ +TRACE_EVENT(workqueue_execute_end, + + TP_PROTO(struct work_struct *work), + + TP_ARGS(work), + + TP_STRUCT__entry( + __field( void *, work ) + ), + + TP_fast_assign( + __entry->work = work; + ), + + TP_printk("work struct %p", __entry->work) +); + + +#endif /* _TRACE_WORKQUEUE_H */ + +/* This part must be outside protection */ +#include -- cgit v1.2.2