diff options
| author | Todd Brandt | 2017-03-02 16:12:15 -0800 |
|---|---|---|
| committer | Steven Rostedt (VMware) | 2017-03-03 09:45:01 -0500 |
| commit | 65a50c656276b0846bea09dd011c0a3d35b77f3e (patch) | |
| tree | f75fe3c818f323dc288fca8ba60dbdcf3b2db2a4 /kernel | |
| parent | bf7165cfa23695c51998231c4efa080fe1d3548d (diff) | |
ftrace/graph: Add ftrace_graph_max_depth kernel parameter
Early trace callgraphs can be extremely large on systems with
several seconds of boot time. The max_depth parameter limits how
deep the graph trace goes and reduces the output size. This
parameter is the same as the max_graph_depth file in tracefs.
Link: http://lkml.kernel.org/r/1488499935-23216-1-git-send-email-todd.e.brandt@linux.intel.com
Signed-off-by: Todd Brandt <todd.e.brandt@linux.intel.com>
[ changed comments about debugfs to tracefs ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/ftrace.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 44122e7a6418..d129ae51329a 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -4415,6 +4415,15 @@ static int __init set_graph_notrace_function(char *str) } __setup("ftrace_graph_notrace=", set_graph_notrace_function); +static int __init set_graph_max_depth_function(char *str) +{ + if (!str) + return 0; + fgraph_max_depth = simple_strtoul(str, NULL, 0); + return 1; +} +__setup("ftrace_graph_max_depth=", set_graph_max_depth_function); + static void __init set_ftrace_early_graph(char *buf, int enable) { int ret; |