Re: [PATCH] tpm: drop chip->is_open and chip->duration_adjusted

[Jarkko Sakkinen]

On Mon, Nov 14, 2016 at 09:30:01PM -0700, Jason Gunthorpe wrote:
> On Mon, Nov 14, 2016 at 03:44:58PM -0800, Jarkko Sakkinen wrote:
> > Use atomic bitops for chip->flags so that we do not need chip->is_open
> > and chip->duration_adjusted anymore.
> 
> I don't know if it s a really great idea to use atomic bit ops for
> things that do not need to be atomic.. It makes the locking scheme
> less clear. is open is genuinely different since it relies on the
> atomic for correctness.

The way I see it is one of the status flags bound to chip among the
others. I do not see this cause too much harm for clarity. It eases
debugging the driver a bit because you get more state out of 'flags'.

It also makes code little a bit more robust as flags is independent of
locks.

How strong is your opposition here? I do not see any exceptional damage
done but see some subtle but still significant benefits.

> Merging is_duration makes lots of sense though

Also timeout_adjusted should be merged (for some reason missed it).

> Jason

/Jarkko