Linux Kernel Markers - Samples

Module example showing how to use the Linux Kernel Markers.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 54 insertions, 0 deletions

diff --git a/samples/markers/marker-example.c b/samples/markers/marker-example.c
new file mode 100644
index 000000000000..e787c6d16dd7
--- /dev/null
+++ b/samples/markers/marker-example.c
@@ -0,0 +1,54 @@
+/* marker-example.c
+ *
+ * Executes a marker when /proc/marker-example 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/marker.h>
+#include <linux/sched.h>
+#include <linux/proc_fs.h>
+
+struct proc_dir_entry *pentry_example;
+
+static int my_open(struct inode *inode, struct file *file)
+{
+	int i;
+
+	trace_mark(subsystem_event, "%d %s", 123, "example string");
+	for (i = 0; i < 10; i++)
+		trace_mark(subsystem_eventb, MARK_NOARGS);
+	return -EPERM;
+}
+
+static struct file_operations mark_ops = {
+	.open = my_open,
+};
+
+static int example_init(void)
+{
+	printk(KERN_ALERT "example init\n");
+	pentry_example = create_proc_entry("marker-example", 0444, NULL);
+	if (pentry_example)
+		pentry_example->proc_fops = &mark_ops;
+	else
+		return -EPERM;
+	return 0;
+}
+
+static void example_exit(void)
+{
+	printk(KERN_ALERT "example exit\n");
+	remove_proc_entry("marker-example", NULL);
+}
+
+module_init(example_init)
+module_exit(example_exit)
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mathieu Desnoyers");
+MODULE_DESCRIPTION("Marker example");