[ltt-dev] [PATCH] Simple LTTng userspace events through debugfs

Randy Dunlap randy.dunlap at oracle.com
Thu Dec 18 11:50:18 EST 2008


On Wed, 17 Dec 2008 12:32:24 -0500 Mathieu Desnoyers wrote:

> Index: linux-2.6-lttng/ltt/ltt-userspace-event.c
> ===================================================================
> --- /dev/null	1970-01-01 00:00:00.000000000 +0000
> +++ linux-2.6-lttng/ltt/ltt-userspace-event.c	2008-12-17 12:03:43.000000000 -0500
> @@ -0,0 +1,129 @@
> +
> +/**
> + * write_event: write a userspace string into the trace stream

Hi Mathieu,

Please make above line:

 * write_event - write a userspace string into the trace system

Thanks.

> + * @file: file pointer
> + * @user_buf: user string
> + * @count: length to copy, including the final NULL
> + * @ppos: unused
> + *
> + * Copy a string into a trace event, in channel "userspace", event "event".
> + * Copies until either \n or \0 is reached.
> + * On success, returns the number of bytes copied from the source, including the
> + * \n or \0 character (if there was one in the count range). It cannot return
> + * more than count.
> + * Inspired from tracing_mark_write implementation from Steven Rostedt and
> + * Ingo Molnar.
> + */
> +static ssize_t write_event(struct file *file, const char __user *user_buf,
> +		size_t count, loff_t *ppos)
> +{


---
~Randy




More information about the lttng-dev mailing list