ftrace: Allow to remove a single function from function graph filter
I don't see why we can only clear all functions from the filter.
After patching:
# echo sys_open > set_graph_function
# echo sys_close >> set_graph_function
# cat set_graph_function
sys_open
sys_close
# echo '!sys_close' >> set_graph_function
# cat set_graph_function
sys_open
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4B726388.2000408@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index ce077fb..b477fce 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -497,6 +497,7 @@
#ifdef CONFIG_DYNAMIC_FTRACE
/* TODO: make this variable */
#define FTRACE_GRAPH_MAX_FUNCS 32
+extern int ftrace_graph_filter_enabled;
extern int ftrace_graph_count;
extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
@@ -504,7 +505,7 @@
{
int i;
- if (!ftrace_graph_count)
+ if (!ftrace_graph_filter_enabled)
return 1;
for (i = 0; i < ftrace_graph_count; i++) {