[PATCH 06/11] tracing: update sample code with new tag format

Steven Rostedt
2009-06-10T17:01:42Z

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From: Steven Rostedt <srostedt@redhat.com>

This patch adds examples of all the new tags in the
samples/trace_events/ example code.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
samples/trace_events/trace-events-sample.c | 21 ++++++++-
samples/trace_events/trace-events-sample.h | 66 ++++++++++++++++++++++++++++
2 files changed, 85 insertions(+), 2 deletions(-)

diff --git a/samples/trace_events/trace-events-sample.c b/samples/trace_events/trace-events-sample.c
index aabc4e9..dea8eb3 100644
--- a/samples/trace_events/trace-events-sample.c
+++ b/samples/trace_events/trace-events-sample.c
@@ -10,12 +10,31 @@
#define CREATE_TRACE_POINTS
#include "trace-events-sample.h"

+static struct task_struct *simple_tsk;

static void simple_thread_func(int cnt)
{
+ static int mask;
+ static int myif;
+
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(HZ);
trace_foo_bar("hello", cnt);
+ trace_format_examples(jiffies,
+ jiffies * 2,
+ "a string here",
+ &simple_tsk,
+ mask, mask, simple_thread_func,
+ myif, myif, cpu_clock(raw_smp_processor_id()),
+ 123456);
+ if (!myif)
+ myif = 3;
+
+ if (!mask)
+ mask = 5;
+
+ mask <<= mask;
+ myif <<= myif;
}

static int simple_thread(void *arg)
@@ -28,8 +47,6 @@ static int simple_thread(void *arg)
return 0;
}

-static struct task_struct *simple_tsk;
-
static int __init trace_event_init(void)
{
simple_tsk = kthread_run(simple_thread, NULL, "event-sample");
diff --git a/samples/trace_events/trace-events-sample.h b/samples/trace_events/trace-events-sample.h
index 128a897..08b4768 100644
--- a/samples/trace_events/trace-events-sample.h
+++ b/samples/trace_events/trace-events-sample.h
@@ -65,6 +65,11 @@
* Note, that for both the assign and the printk, __entry is the handler
* to the data structure in the ring buffer, and is defined by the
* TP_STRUCT__entry.
+ *
+ * Note it is better to now use the tag format. Examples are in the event
+ * below, and the explanation of the tag format language is in:
+ *
+ * kernel/trace/trace_read_binary.h
*/
TRACE_EVENT(foo_bar,

@@ -84,6 +89,67 @@ TRACE_EVENT(foo_bar,

TP_printk("foo %s %d", __entry->foo, __entry->bar)
);
+
+/*
+ * These are a few examples of the tag format to do the output.
+ */
+TRACE_EVENT(format_examples,
+
+ TP_PROTO(int myint, long mylong, char *mystr, void *myptr,
+ unsigned long mask, unsigned sym, void *func,
+ int myif, int myifmask, unsigned long long nsec,
+ int dev),
+
+ TP_ARGS(myint, mylong, mystr, myptr, mask, sym, func,
+ myif, myifmask, nsec, dev),
+
+ TP_STRUCT__entry(
+ __field( int, myint )
+ __field( long, mylong )
+ __string(str, mystr)
+ __array( char, str_arr, 20 )
+ __field( void *, func )
+ __field( int, myif )
+ __field( unsigned long, mask )
+ __field( unsigned long, sym )
+ __field( int, myifmask )
+ __field( int, dev )
+ __field( unsigned long long, nsec )
+ ),
+
+ TP_fast_assign(
+ __entry->myint = myint;
+ __entry->mylong = mylong;
+ __assign_str(str, mystr);
+ strncpy(__entry->str_arr, mystr, 19);
+ __entry->str_arr[19] = 0;
+ __entry->mask = mask;
+ __entry->sym = sym;
+ __entry->func = func;
+ __entry->myif = myif;
+ __entry->myifmask = myifmask;
+ __entry->dev = dev;
+ __entry->nsec = nsec;
+ ),
+
+ TP_FORMAT("to see a normal int <int:myint> \n"
+ "or perhaps make it unsigned <uint:myint>\n"
+ "no difference for the size <int:mylong>\n"
+ "lets make it into a hex <hex:myint>\n"
+ "dynamic strings are simple <string:str>\n"
+ "and so are static ones <strarray:str_arr>\n"
+ "see a func and offset <symfunc:func>\n"
+ "or just the func name <func:func>\n"
+ "should we print <if:myif:this:that>\n"
+ "or base it on a bit mask <ifmask:myif:0xc:foo:bar>\n"
+ "we want to see that device <major:dev>,<minor:dev>\n"
+ "we can see masks <mask:mask:,:0=nothing,0xa=a,1=one,2=two>\n"
+ "or values of symbols <sym:sym:1=this,2=that,3=nevermind>\n"
+ "and know what time it is in seconds <nsec2sec:6:nsec> \n"
+ "millisecs <nsec2msec:6:nsec>\n"
+ "or microsecs <nsec2usec:3:nsec>")
+);
+
#endif

/***** NOTICE! The #if protection ends here. *****/
--
1.6.3.1

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