ftrace: startup tester on dynamic tracing.
This patch adds a startup self test on dynamic code modification
and filters. The test filters on a specific function, makes sure that
no other function is traced, exectutes the function, then makes sure that
the function is traced.
This patch also fixes a slight bug with the ftrace selftest, where
tracer_enabled was not being set.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 6d4d2e8..5e9389f 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1010,6 +1010,25 @@
return ret;
}
+/**
+ * ftrace_set_filter - set a function to filter on in ftrace
+ * @buf - the string that holds the function filter text.
+ * @len - the length of the string.
+ * @reset - non zero to reset all filters before applying this filter.
+ *
+ * Filters denote which functions should be enabled when tracing is enabled.
+ * If @buf is NULL and reset is set, all functions will be enabled for tracing.
+ */
+notrace void ftrace_set_filter(unsigned char *buf, int len, int reset)
+{
+ mutex_lock(&ftrace_filter_lock);
+ if (reset)
+ ftrace_filter_reset();
+ if (buf)
+ ftrace_match(buf, len);
+ mutex_unlock(&ftrace_filter_lock);
+}
+
static int notrace
ftrace_filter_release(struct inode *inode, struct file *file)
{