Re: [PATCH v10 08/26] gunyah: rsc_mgr: Add resource manager RPC core

[Elliot Berman]

On 2/15/2023 10:43 PM, Greg Kroah-Hartman wrote:
> On Tue, Feb 14, 2023 at 01:23:25PM -0800, Elliot Berman wrote:
> > +struct gh_rm {
> > +	struct device *dev;
>
> What device does this point to?

The platform device.

> > +	struct gunyah_resource tx_ghrsc, rx_ghrsc;
> > +	struct gh_msgq msgq;
> > +	struct mbox_client msgq_client;
> > +	struct gh_rm_connection *active_rx_connection;
> > +	int last_tx_ret;
> > +
> > +	struct idr call_idr;
> > +	struct mutex call_idr_lock;
> > +
> > +	struct kmem_cache *cache;
> > +	struct mutex send_lock;
> > +	struct blocking_notifier_head nh;
> > +};
>
> This obviously is the "device" that your system works on, so what are
> the lifetime rules of it?  Why isn't is just a real 'struct device' in
> the system instead of a random memory blob with a pointer to a device?
>
> What controls the lifetime of this structure and where is the reference
> counting logic for it?

The lifetime of the structure is bound by the platform device that above 
struct device *dev points to. get_gh_rm and put_gh_rm increments the 
device ref counter and ensures lifetime of the struct is also extended.

> And why no documentation for this core structure?

Sure, I will add.

> thanks,
>
> greg k-h