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

Arve Hjønnevåg
2010-04-28T23:38:04Z

2010/4/28 Rafael J. Wysocki <rjw@sisk.pl>:
> On Thursday 29 April 2010, Arve Hjønnevåg wrote:
>> 2010/4/28 Rafael J. Wysocki <rjw@sisk.pl>:
>> > 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@android.com>
>> > ...
>> >> +
>> >> +#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.

I may want to add a bit to print all user-space block and unblock calls.

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

OK.

--
Arve Hjønnevåg