Re: [RFC PATCH 2/3] Generic Trace Setup and Control (GTSC) code

[Mathieu Desnoyers <compudj@krystal.dyndns.org>]

* Tom Zanussi (zanussi@us.ibm.com) wrote:
> The Generic Tracing and Control Interface (GTSC) code.
> 
> Signed-off-by: Tom Zanussi <zanussi@us.ibm.com>
> Signed-off-by: David Wilder <dwilder@us.ibm.com>
> ---
>  include/linux/gtsc.h |  104 +++++++++
>  lib/Kconfig          |   10 
>  lib/Makefile         |    2 
>  lib/gtsc.c           |  558 +++++++++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 674 insertions(+)
> 
....
> +static ssize_t reset_consumed_write(struct file *filp,
> +				    const char __user *buffer,
> +				    size_t count,
> +				    loff_t *ppos)
> +{
> +	struct trace_info *trace = filp->private_data;
> +
> +	relay_reset_consumed(trace->rchan);
> +
> +	return count;
> +}
> +
> +struct file_operations reset_consumed_fops = {
> +	.owner	= THIS_MODULE,
> +	.open	= reset_consumed_open,
> +	.write	= reset_consumed_write
> +};
> +

Quoting the header of relay_reset_consumed:

+ *     NOTE: Care should be taken that the channel isn't actually
+ *     being used by anything when this call is made.

I can imagine relay saying "locking is not my problem", while GTSC
whistle and looks away... ;)


-- 
Mathieu Desnoyers
Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68