Re: [PATCH 2/8] PM: suspend_block: Add driver to access suspend blockers from user-space

From: Rafael J. Wysocki
Date: Wed Apr 28 2010 - 19:04:59 EST


On Thursday 29 April 2010, Arve Hjønnevåg wrote:
> 2010/4/28 Rafael J. Wysocki <rjw@xxxxxxx>:
> > On Wednesday 28 April 2010, Arve Hjønnevåg wrote:
> >> Add a misc device, "suspend_blocker", that allows user-space processes
> >> to block auto suspend. The device has ioctls to create a suspend_blocker,
> >> and to block and unblock suspend. To delete the suspend_blocker, close
> >> the device.
> >>
> >> Signed-off-by: Arve Hjønnevåg <arve@xxxxxxxxxxx>
> > ...
> >> +
> >> +#include <linux/fs.h>
> >> +#include <linux/miscdevice.h>
> >> +#include <linux/module.h>
> >> +#include <linux/uaccess.h>
> >> +#include <linux/slab.h>
> >> +#include <linux/suspend_blocker.h>
> >> +#include <linux/suspend_block_dev.h>
> >> +
> >> +enum {
> >> + DEBUG_FAILURE = BIT(0),
> >> +};
> >> +static int debug_mask = DEBUG_FAILURE;
> >
> > What's the exact purpose of this?
>
> To show errors returned to user space. I can turn it off by default if you want.

Not necessarily, but why is it a mask? It looks like a 0/1 thing would be
sufficient.

BTW, I'd put parens around (debug_mask & DEBUG_FAILURE) for clarity.

Rafael
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/