Commit graph

8 commits

Author SHA1 Message Date
Linus Torvalds
b83c2880b3 Fix tracing sample code warning.
commit a0cb2b5c390151837b08e5f7bca4a6ecddbcd39c upstream.

Commit 6575257c60e1 ("tracing/samples: Fix creation and deletion of
simple_thread_fn creation") introduced a new warning due to using a
boolean as a counter.

Just make it "int".

Fixes: 6575257c60e1 ("tracing/samples: Fix creation and deletion of simple_thread_fn creation")
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08 10:06:28 +01:00
Steven Rostedt (VMware)
a48fce6623 tracing/samples: Fix creation and deletion of simple_thread_fn creation
commit 6575257c60e1a26a5319ccf2b5ce5b6449001017 upstream.

Commit 7496946a8 ("tracing: Add samples of DECLARE_EVENT_CLASS() and
DEFINE_EVENT()") added template examples for all the events. It created a
DEFINE_EVENT_FN() example which reused the foo_bar_reg and foo_bar_unreg
functions.

Enabling both the TRACE_EVENT_FN() and DEFINE_EVENT_FN() example trace
events caused the foo_bar_reg to be called twice, creating the test thread
twice. The foo_bar_unreg would remove it only once, even if it was called
multiple times, leaving a thread existing when the module is unloaded,
causing an oops.

Add a ref count and allow foo_bar_reg() and foo_bar_unreg() be called by
multiple trace events.

Fixes: 7496946a8 ("tracing: Add samples of DECLARE_EVENT_CLASS() and DEFINE_EVENT()")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08 10:06:28 +01:00
Steven Rostedt (Red Hat)
7496946a88 tracing: Add samples of DECLARE_EVENT_CLASS() and DEFINE_EVENT()
Add to samples/trace_events/ the macros DECLARE_EVENT_CLASS() and
DEFINE_EVENT() and recommend using them over multiple TRACE_EVENT()
macros if the multiple events have the same format.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-02-09 18:05:51 -05:00
Steven Rostedt (Red Hat)
6adc13f8c0 tracing: Add TRACE_EVENT_FN example
If a function should be called before a tracepoint is enabled
and/or after it is disabled, the TRACE_EVENT_FN() serves this
purpose. But it is not well documented. Having it as a sample would
help developers to know how to use it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-02-09 18:05:39 -05:00
Steven Rostedt (Red Hat)
c4c7eb2938 tracing: Add TRACE_EVENT_CONDITION sample
The sample code lacks an example of TRACE_EVENT_CONDITION, and it
has been expressed to me that this feature for TRACE_EVENT is not
well known and not used when it could be.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-02-09 16:05:55 -05:00
Steven Rostedt (Red Hat)
4e20e3a60b tracing: Update the TRACE_EVENT fields available in the sample code
The sample code in samples/trace_events/ is extremely out of date and does
not show all the new fields that have been added since the sample code
was written. As most people are unaware of these new fields, adding sample
code and explanations of those fields should help out.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-02-09 15:27:04 -05:00
Li Zefan
fd6da10a61 tracing/events: don't say hi when loading the trace event sample
The sample is useful for testing, and I'm using it. But after
loading the module, it keeps saying hi every 10 seconds, this may
be disturbing.

Also Steven said commenting out the "hi" helped in causing races. :)

[ Impact: make testing a bit easier ]

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A00F6AD.2070008@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-06 10:38:18 +02:00
Steven Rostedt
9cfe06f8cd tracing/events: add trace-events-sample
This patch adds a sample to the samples directory on how to create
and use TRACE_EVENT trace points.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-04-14 22:09:18 -04:00