add workqueue support

2 files changed, 193 insertions, 0 deletions

diff --git a/patches/0001-tracing-Make-timer-tracing-actually-useful.patch b/patches/0001-tracing-Make-timer-tracing-actually-useful.patch
new file mode 100644
index 0000000..1d8e21b
--- /dev/null
+++ b/patches/0001-tracing-Make-timer-tracing-actually-useful.patch
@@ -0,0 +1,64 @@
+From fe9633af11395d339880417439a1931bb9e7e493 Mon Sep 17 00:00:00 2001
+From: Arjan van de Ven <arjan@linux.intel.com>
+Date: Wed, 18 Aug 2010 15:28:59 -0400
+Subject: [PATCH] tracing: Make timer tracing actually useful
+
+PowerTOP would like to be able to trace timers.
+Unfortunately, the current timer tracing is not very useful, the actual
+timer function is not recorded in the trace at the start of timer execution.
+
+Although this is recorded for timer "start" time (when it gets armed), this
+is not useful; most timers get started early, and a tracer like PowerTOP
+will never see this event, but will only see the actual running of the timer.
+
+This patch just adds the function to the timer tracing; I've verified with
+PowerTOP that now it can get useful information about timers.
+
+Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
+---
+ include/trace/events/timer.h |    8 ++++++--
+ 1 files changed, 6 insertions(+), 2 deletions(-)
+
+diff --git a/include/trace/events/timer.h b/include/trace/events/timer.h
+index c624126..94511c8 100644
+--- a/include/trace/events/timer.h
++++ b/include/trace/events/timer.h
+@@ -81,14 +81,16 @@ TRACE_EVENT(timer_expire_entry,
+ 	TP_STRUCT__entry(
+ 		__field( void *,	timer	)
+ 		__field( unsigned long,	now	)
++		__field( void *,	function	)
+ 	),
+ 
+ 	TP_fast_assign(
+ 		__entry->timer		= timer;
+ 		__entry->now		= jiffies;
++		__entry->function	= timer->function;
+ 	),
+ 
+-	TP_printk("timer=%p now=%lu", __entry->timer, __entry->now)
++	TP_printk("timer=%p function=%pf now=%lu", __entry->timer, __entry->function,__entry->now)
+ );
+ 
+ /**
+@@ -200,14 +202,16 @@ TRACE_EVENT(hrtimer_expire_entry,
+ 	TP_STRUCT__entry(
+ 		__field( void *,	hrtimer	)
+ 		__field( s64,		now	)
++		__field( void *,	function	)
+ 	),
+ 
+ 	TP_fast_assign(
+ 		__entry->hrtimer	= hrtimer;
+ 		__entry->now		= now->tv64;
++		__entry->function	= hrtimer->function;
+ 	),
+ 
+-	TP_printk("hrtimer=%p now=%llu", __entry->hrtimer,
++	TP_printk("hrtimer=%p function=%pf now=%llu", __entry->hrtimer, __entry->function,
+ 		  (unsigned long long)ktime_to_ns((ktime_t) { .tv64 = __entry->now }))
+  );
+ 
+-- 
+1.6.1.3
+
diff --git a/patches/0001-workqueue-Add-basic-tracepoints-to-track-workqueue-e.patch b/patches/0001-workqueue-Add-basic-tracepoints-to-track-workqueue-e.patch
new file mode 100644
index 0000000..11db56b
--- /dev/null
+++ b/patches/0001-workqueue-Add-basic-tracepoints-to-track-workqueue-e.patch
@@ -0,0 +1,129 @@
+From 1fd789ef484066ed5583c94dc03ef066cc1c0d94 Mon Sep 17 00:00:00 2001
+From: Arjan van de Ven <arjan@linux.intel.com>
+Date: Sat, 21 Aug 2010 13:07:26 -0700
+Subject: [PATCH] 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 <arjan@linux.intel.com>
+---
+ include/trace/events/workqueue.h |   63 ++++++++++++++++++++++++++++++++++++++
+ kernel/workqueue.c               |    9 +++++
+ 2 files changed, 72 insertions(+), 0 deletions(-)
+ create mode 100644 include/trace/events/workqueue.h
+
+diff --git a/include/trace/events/workqueue.h b/include/trace/events/workqueue.h
+new file mode 100644
+index 0000000..4fd2bd1
+--- /dev/null
++++ b/include/trace/events/workqueue.h
+@@ -0,0 +1,63 @@
++#undef TRACE_SYSTEM
++#define TRACE_SYSTEM workqueue
++
++#if !defined(_TRACE_WORKQUEUE_H) || defined(TRACE_HEADER_MULTI_READ)
++#define _TRACE_WORKQUEUE_H
++
++#include <linux/tracepoint.h>
++#include <linux/workqueue.h>
++
++/**
++ * 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 <trace/define_trace.h>
++
+diff --git a/kernel/workqueue.c b/kernel/workqueue.c
+index 2994a0e..8bd600c 100644
+--- a/kernel/workqueue.c
++++ b/kernel/workqueue.c
+@@ -35,6 +35,9 @@
+ #include <linux/lockdep.h>
+ #include <linux/idr.h>
+ 
++#define CREATE_TRACE_POINTS
++#include <trace/events/workqueue.h>
++
+ #include "workqueue_sched.h"
+ 
+ enum {
+@@ -1790,7 +1793,13 @@ static void process_one_work(struct worker *worker, struct work_struct *work)
+ 	work_clear_pending(work);
+ 	lock_map_acquire(&cwq->wq->lockdep_map);
+ 	lock_map_acquire(&lockdep_map);
++	trace_workqueue_execute_start(work);
+ 	f(work);
++	/*
++	 * While we must be careful to not use "work" after this, the trace
++	 * point will only record its address.
++	 */
++	trace_workqueue_execute_end(work);
+ 	lock_map_release(&lockdep_map);
+ 	lock_map_release(&cwq->wq->lockdep_map);
+ 
+-- 
+1.7.1.1
+