ftrace: use task struct trace flag to filter on pid
Impact: clean up Use the new task struct trace flags to determine if a process should be traced or not. Note: this moves the searching of the pid to the slow path of setting the pid field. This needs to be converted to the pid name space. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
parent
ea4e2bc4d9
commit
0ef8cde56a
1 changed files with 25 additions and 3 deletions
|
@ -47,7 +47,7 @@
|
|||
int ftrace_enabled __read_mostly;
|
||||
static int last_ftrace_enabled;
|
||||
|
||||
/* ftrace_pid_trace >= 0 will only trace threads with this pid */
|
||||
/* set when tracing only a pid */
|
||||
static int ftrace_pid_trace = -1;
|
||||
|
||||
/* Quick disabling of function tracer. */
|
||||
|
@ -90,7 +90,7 @@ static void ftrace_list_func(unsigned long ip, unsigned long parent_ip)
|
|||
|
||||
static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip)
|
||||
{
|
||||
if (current->pid != ftrace_pid_trace)
|
||||
if (!test_tsk_trace_trace(current))
|
||||
return;
|
||||
|
||||
ftrace_pid_function(ip, parent_ip);
|
||||
|
@ -1714,11 +1714,33 @@ ftrace_pid_write(struct file *filp, const char __user *ubuf,
|
|||
ftrace_pid_trace = -1;
|
||||
|
||||
} else {
|
||||
struct task_struct *p;
|
||||
int found = 0;
|
||||
|
||||
if (ftrace_pid_trace == val)
|
||||
goto out;
|
||||
|
||||
/*
|
||||
* Find the task that matches this pid.
|
||||
* TODO: use pid namespaces instead.
|
||||
*/
|
||||
rcu_read_lock();
|
||||
for_each_process(p) {
|
||||
if (p->pid == val) {
|
||||
found = 1;
|
||||
set_tsk_trace_trace(p);
|
||||
} else if (test_tsk_trace_trace(p))
|
||||
clear_tsk_trace_trace(p);
|
||||
}
|
||||
rcu_read_unlock();
|
||||
|
||||
if (found)
|
||||
ftrace_pid_trace = val;
|
||||
else {
|
||||
if (ftrace_pid_trace < 0)
|
||||
goto out;
|
||||
ftrace_pid_trace = -1;
|
||||
}
|
||||
}
|
||||
|
||||
/* update the function call */
|
||||
|
|
Reference in a new issue