tracing: add saved_cmdlines file to show cached task comms

	.read		= tracing_readme_read,

};

static ssize_t

tracing_saved_cmdlines_read(struct file *file, char __user *ubuf,

				size_t cnt, loff_t *ppos)

{

	char *buf_comm;

	char *file_buf;

	char *buf;

	int len = 0;

	int pid;

	int i;

	file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL);

	if (!file_buf)

		return -ENOMEM;

	buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL);

	if (!buf_comm) {

		kfree(file_buf);

		return -ENOMEM;

	}

	buf = file_buf;

	for (i = 0; i < SAVED_CMDLINES; i++) {

		int r;

		pid = map_cmdline_to_pid[i];

		if (pid == -1 || pid == NO_CMDLINE_MAP)

			continue;

		trace_find_cmdline(pid, buf_comm);

		r = sprintf(buf, "%d %s\n", pid, buf_comm);

		buf += r;

		len += r;

	}

	len = simple_read_from_buffer(ubuf, cnt, ppos,

				      file_buf, len);

	kfree(file_buf);

	kfree(buf_comm);

	return len;

}

static const struct file_operations tracing_saved_cmdlines_fops = {

    .open       = tracing_open_generic,

    .read       = tracing_saved_cmdlines_read,

};

static ssize_t

tracing_ctrl_read(struct file *filp, char __user *ubuf,

		  size_t cnt, loff_t *ppos)

	trace_create_file("trace_marker", 0220, d_tracer,

			NULL, &tracing_mark_fops);

	trace_create_file("saved_cmdlines", 0444, d_tracer,

			NULL, &tracing_saved_cmdlines_fops);

#ifdef CONFIG_DYNAMIC_FTRACE

	trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,

			&ftrace_update_tot_cnt, &tracing_dyn_info_fops);