tracing: Have stack_tracer use a separate list of functions

The stack_tracer is used to look at every function and check
if the current stack is bigger than the last recorded max stack size.
When a new max is found, then it saves that stack off.

Currently the stack tracer is limited by the global_ops of
the function tracer. As the stack tracer has nothing to do with
the ftrace function tracer, except that it uses it as its internal
engine, the stack tracer should have its own list.

A new file is added to the tracing debugfs directory called:

  stack_trace_filter

that can be used to select which functions you want to check the stack
on.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt 2011-12-19 14:44:09 -05:00 committed by Steven Rostedt
parent 69a3083c4a
commit d2d45c7a03

View File

@ -133,7 +133,6 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __read_mostly = static struct ftrace_ops trace_ops __read_mostly =
{ {
.func = stack_trace_call, .func = stack_trace_call,
.flags = FTRACE_OPS_FL_GLOBAL,
}; };
static ssize_t static ssize_t
@ -311,6 +310,21 @@ static const struct file_operations stack_trace_fops = {
.release = seq_release, .release = seq_release,
}; };
static int
stack_trace_filter_open(struct inode *inode, struct file *file)
{
return ftrace_regex_open(&trace_ops, FTRACE_ITER_FILTER,
inode, file);
}
static const struct file_operations stack_trace_filter_fops = {
.open = stack_trace_filter_open,
.read = seq_read,
.write = ftrace_filter_write,
.llseek = ftrace_regex_lseek,
.release = ftrace_regex_release,
};
int int
stack_trace_sysctl(struct ctl_table *table, int write, stack_trace_sysctl(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, void __user *buffer, size_t *lenp,
@ -358,6 +372,9 @@ static __init int stack_trace_init(void)
trace_create_file("stack_trace", 0444, d_tracer, trace_create_file("stack_trace", 0444, d_tracer,
NULL, &stack_trace_fops); NULL, &stack_trace_fops);
trace_create_file("stack_trace_filter", 0444, d_tracer,
NULL, &stack_trace_filter_fops);
if (stack_tracer_enabled) if (stack_tracer_enabled)
register_ftrace_function(&trace_ops); register_ftrace_function(&trace_ops);