lttng-instrumentation/revert-marker-remove

revert marker remove

LTTng tree (internal).

revert commit fc5377668c3d808e1d53c4aee152c836f55c3490

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>

5 files changed, 156 insertions, 1 deletions

diff --git a/samples/Kconfig b/samples/Kconfig
index e03cf0e374d..7b1eadec88a 100644
--- a/samples/Kconfig
+++ b/samples/Kconfig
@@ -5,6 +5,12 @@ menuconfig SAMPLES
 
 if SAMPLES
 
+config SAMPLE_MARKERS
+	tristate "Build markers examples -- loadable modules only"
+	depends on MARKERS && m
+	help
+	  This build markers example modules.
+
 config SAMPLE_TRACEPOINTS
 	tristate "Build tracepoints examples -- loadable modules only"
 	depends on TRACEPOINTS && m
diff --git a/samples/Makefile b/samples/Makefile
index f26c0959fd8..ab354640197 100644
--- a/samples/Makefile
+++ b/samples/Makefile
@@ -1,4 +1,4 @@
 # Makefile for Linux samples code
 
 obj-$(CONFIG_SAMPLES)	+= kobject/ kprobes/ tracepoints/ trace_events/ \
-			   hw_breakpoint/ kfifo/ kdb/
+			   hw_breakpoint/ kfifo/ kdb/ markers/
diff --git a/samples/markers/Makefile b/samples/markers/Makefile
new file mode 100644
index 00000000000..6d7231265f0
--- /dev/null
+++ b/samples/markers/Makefile
@@ -0,0 +1,4 @@
+# builds the kprobes example kernel modules;
+# then to use one (as root):  insmod <module_name.ko>
+
+obj-$(CONFIG_SAMPLE_MARKERS) += probe-example.o marker-example.o
diff --git a/samples/markers/marker-example.c b/samples/markers/marker-example.c
new file mode 100644
index 00000000000..e9cd9c0bc84
--- /dev/null
+++ b/samples/markers/marker-example.c
@@ -0,0 +1,53 @@
+/* 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, "integer %d string %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 __init example_init(void)
+{
+	printk(KERN_ALERT "example init\n");
+	pentry_example = proc_create("marker-example", 0444, NULL, &mark_ops);
+	if (!pentry_example)
+		return -EPERM;
+	return 0;
+}
+
+static void __exit 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");
diff --git a/samples/markers/probe-example.c b/samples/markers/probe-example.c
new file mode 100644
index 00000000000..2dfb3b32937
--- /dev/null
+++ b/samples/markers/probe-example.c
@@ -0,0 +1,92 @@
+/* probe-example.c
+ *
+ * Connects two functions to marker call sites.
+ *
+ * (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/sched.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/marker.h>
+#include <asm/atomic.h>
+
+struct probe_data {
+	const char *name;
+	const char *format;
+	marker_probe_func *probe_func;
+};
+
+void probe_subsystem_event(void *probe_data, void *call_data,
+	const char *format, va_list *args)
+{
+	/* Declare args */
+	unsigned int value;
+	const char *mystr;
+
+	/* Assign args */
+	value = va_arg(*args, typeof(value));
+	mystr = va_arg(*args, typeof(mystr));
+
+	/* Call printk */
+	printk(KERN_INFO "Value %u, string %s\n", value, mystr);
+
+	/* or count, check rights, serialize data in a buffer */
+}
+
+atomic_t eventb_count = ATOMIC_INIT(0);
+
+void probe_subsystem_eventb(void *probe_data, void *call_data,
+	const char *format, va_list *args)
+{
+	/* Increment counter */
+	atomic_inc(&eventb_count);
+}
+
+static struct probe_data probe_array[] =
+{
+	{	.name = "subsystem_event",
+		.format = "integer %d string %s",
+		.probe_func = probe_subsystem_event },
+	{	.name = "subsystem_eventb",
+		.format = MARK_NOARGS,
+		.probe_func = probe_subsystem_eventb },
+};
+
+static int __init probe_init(void)
+{
+	int result;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(probe_array); i++) {
+		result = marker_probe_register(probe_array[i].name,
+				probe_array[i].format,
+				probe_array[i].probe_func, &probe_array[i]);
+		if (result)
+			printk(KERN_INFO "Unable to register probe %s\n",
+				probe_array[i].name);
+	}
+	return 0;
+}
+
+static void __exit probe_fini(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(probe_array); i++)
+		marker_probe_unregister(probe_array[i].name,
+			probe_array[i].probe_func, &probe_array[i]);
+	printk(KERN_INFO "Number of event b : %u\n",
+			atomic_read(&eventb_count));
+	marker_synchronize_unregister();
+}
+
+module_init(probe_init);
+module_exit(probe_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mathieu Desnoyers");
+MODULE_DESCRIPTION("SUBSYSTEM Probe");