tracing: Remove tracepoint sample code

The tracepoint sample code was used to teach developers how to
create their own tracepoints. But now the trace_events have been
added as a higher level that is used directly by developers today.

Only the trace_event code should use the tracepoint interface
directly and no new tracepoints should be added.

Besides, the example had a race condition with the use of the
 ->d_name.name dentry field, as pointed out by Al Viro.

Best just to remove the code so it wont be used by other developers.

Link: http://lkml.kernel.org/r/20130123225523.GY4939@ZenIV.linux.org.uk
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --git a/samples/Kconfig b/samples/Kconfig
index 7b6792a18c051a94438493c55513f0c47c4d3483..6181c2cc9ca06221047025771950bfc37eb8ca7e 100644 (file)
--- a/samples/Kconfig
+++ b/samples/Kconfig
@@ -5,12 +5,6 @@ menuconfig SAMPLES
 
 if SAMPLES
 
-config SAMPLE_TRACEPOINTS
-       tristate "Build tracepoints examples -- loadable modules only"
-       depends on TRACEPOINTS && m
-       help
-         This build tracepoints example modules.
-
 config SAMPLE_TRACE_EVENTS
        tristate "Build trace_events examples -- loadable modules only"
        depends on EVENT_TRACING && m

diff --git a/samples/Makefile b/samples/Makefile
index 5ef08bba96ceaf817adff74aa4969e3bfdf3c37f..1a60c62e20454eeb8961fb9be7f80d2eaabef3fa 100644 (file)
--- a/samples/Makefile
+++ b/samples/Makefile
@@ -1,4 +1,4 @@
 # Makefile for Linux samples code
 
-obj-$(CONFIG_SAMPLES)  += kobject/ kprobes/ tracepoints/ trace_events/ \
+obj-$(CONFIG_SAMPLES)  += kobject/ kprobes/ trace_events/ \
                           hw_breakpoint/ kfifo/ kdb/ hidraw/ rpmsg/ seccomp/

diff --git a/samples/tracepoints/Makefile b/samples/tracepoints/Makefile
deleted file mode 100644 (file)
index 36479ad..0000000
--- a/samples/tracepoints/Makefile
+++ /dev/null
@@ -1,6 +0,0 @@
-# builds the tracepoint example kernel modules;
-# then to use one (as root):  insmod <module_name.ko>
-
-obj-$(CONFIG_SAMPLE_TRACEPOINTS) += tracepoint-sample.o
-obj-$(CONFIG_SAMPLE_TRACEPOINTS) += tracepoint-probe-sample.o
-obj-$(CONFIG_SAMPLE_TRACEPOINTS) += tracepoint-probe-sample2.o

diff --git a/samples/tracepoints/tp-samples-trace.h b/samples/tracepoints/tp-samples-trace.h
deleted file mode 100644 (file)
index 4d46be9..0000000
--- a/samples/tracepoints/tp-samples-trace.h
+++ /dev/null
@@ -1,11 +0,0 @@
-#ifndef _TP_SAMPLES_TRACE_H
-#define _TP_SAMPLES_TRACE_H
-
-#include <linux/proc_fs.h>     /* for struct inode and struct file */
-#include <linux/tracepoint.h>
-
-DECLARE_TRACE(subsys_event,
-       TP_PROTO(struct inode *inode, struct file *file),
-       TP_ARGS(inode, file));
-DECLARE_TRACE_NOARGS(subsys_eventb);
-#endif

diff --git a/samples/tracepoints/tracepoint-probe-sample.c b/samples/tracepoints/tracepoint-probe-sample.c
deleted file mode 100644 (file)
index 744c0b9..0000000
--- a/samples/tracepoints/tracepoint-probe-sample.c
+++ /dev/null
@@ -1,57 +0,0 @@
-/*
- * tracepoint-probe-sample.c
- *
- * sample tracepoint probes.
- */
-
-#include <linux/module.h>
-#include <linux/file.h>
-#include <linux/dcache.h>
-#include "tp-samples-trace.h"
-
-/*
- * Here the caller only guarantees locking for struct file and struct inode.
- * Locking must therefore be done in the probe to use the dentry.
- */
-static void probe_subsys_event(void *ignore,
-                              struct inode *inode, struct file *file)
-{
-       path_get(&file->f_path);
-       dget(file->f_path.dentry);
-       printk(KERN_INFO "Event is encountered with filename %s\n",
-               file->f_path.dentry->d_name.name);
-       dput(file->f_path.dentry);
-       path_put(&file->f_path);
-}
-
-static void probe_subsys_eventb(void *ignore)
-{
-       printk(KERN_INFO "Event B is encountered\n");
-}
-
-static int __init tp_sample_trace_init(void)
-{
-       int ret;
-
-       ret = register_trace_subsys_event(probe_subsys_event, NULL);
-       WARN_ON(ret);
-       ret = register_trace_subsys_eventb(probe_subsys_eventb, NULL);
-       WARN_ON(ret);
-
-       return 0;
-}
-
-module_init(tp_sample_trace_init);
-
-static void __exit tp_sample_trace_exit(void)
-{
-       unregister_trace_subsys_eventb(probe_subsys_eventb, NULL);
-       unregister_trace_subsys_event(probe_subsys_event, NULL);
-       tracepoint_synchronize_unregister();
-}
-
-module_exit(tp_sample_trace_exit);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Mathieu Desnoyers");
-MODULE_DESCRIPTION("Tracepoint Probes Samples");

diff --git a/samples/tracepoints/tracepoint-probe-sample2.c b/samples/tracepoints/tracepoint-probe-sample2.c
deleted file mode 100644 (file)
index 9fcf990..0000000
--- a/samples/tracepoints/tracepoint-probe-sample2.c
+++ /dev/null
@@ -1,44 +0,0 @@
-/*
- * tracepoint-probe-sample2.c
- *
- * 2nd sample tracepoint probes.
- */
-
-#include <linux/module.h>
-#include <linux/fs.h>
-#include "tp-samples-trace.h"
-
-/*
- * Here the caller only guarantees locking for struct file and struct inode.
- * Locking must therefore be done in the probe to use the dentry.
- */
-static void probe_subsys_event(void *ignore,
-                              struct inode *inode, struct file *file)
-{
-       printk(KERN_INFO "Event is encountered with inode number %lu\n",
-               inode->i_ino);
-}
-
-static int __init tp_sample_trace_init(void)
-{
-       int ret;
-
-       ret = register_trace_subsys_event(probe_subsys_event, NULL);
-       WARN_ON(ret);
-
-       return 0;
-}
-
-module_init(tp_sample_trace_init);
-
-static void __exit tp_sample_trace_exit(void)
-{
-       unregister_trace_subsys_event(probe_subsys_event, NULL);
-       tracepoint_synchronize_unregister();
-}
-
-module_exit(tp_sample_trace_exit);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Mathieu Desnoyers");
-MODULE_DESCRIPTION("Tracepoint Probes Samples");

diff --git a/samples/tracepoints/tracepoint-sample.c b/samples/tracepoints/tracepoint-sample.c
deleted file mode 100644 (file)
index f4d89e0..0000000
--- a/samples/tracepoints/tracepoint-sample.c
+++ /dev/null
@@ -1,57 +0,0 @@
-/* tracepoint-sample.c
- *
- * Executes a tracepoint when /proc/tracepoint-sample is opened.
- *
- * (C) Copyright 2007 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
- *
- * This file is released under the GPLv2.
- * See the file COPYING for more details.
- */
-
-#include <linux/module.h>
-#include <linux/sched.h>
-#include <linux/proc_fs.h>
-#include "tp-samples-trace.h"
-
-DEFINE_TRACE(subsys_event);
-DEFINE_TRACE(subsys_eventb);
-
-struct proc_dir_entry *pentry_sample;
-
-static int my_open(struct inode *inode, struct file *file)
-{
-       int i;
-
-       trace_subsys_event(inode, file);
-       for (i = 0; i < 10; i++)
-               trace_subsys_eventb();
-       return -EPERM;
-}
-
-static const struct file_operations mark_ops = {
-       .open = my_open,
-       .llseek = noop_llseek,
-};
-
-static int __init sample_init(void)
-{
-       printk(KERN_ALERT "sample init\n");
-       pentry_sample = proc_create("tracepoint-sample", 0444, NULL,
-               &mark_ops);
-       if (!pentry_sample)
-               return -EPERM;
-       return 0;
-}
-
-static void __exit sample_exit(void)
-{
-       printk(KERN_ALERT "sample exit\n");
-       remove_proc_entry("tracepoint-sample", NULL);
-}
-
-module_init(sample_init)
-module_exit(sample_exit)
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Mathieu Desnoyers");
-MODULE_DESCRIPTION("Tracepoint sample");