RE: [Patch v3 03/12] net: mana: Handle vport sharing between devices

[Long Li]

> Subject: Re: [Patch v3 03/12] net: mana: Handle vport sharing between
> devices
> 
> From: longli@xxxxxxxxxxxxxxxxx
> Date: Sun, 12 Jun 2022 14:14:45 -0700
> 
> > +int mana_cfg_vport(struct mana_port_context *apc, u32
> protection_dom_id,
> > +		   u32 doorbell_pg_id)
> >  {
> > +	/* Ethernet driver and IB driver can't take the port at the same time
> */
> > +	refcount_inc(&apc->port_use_count);
> > +	if (refcount_read(&apc->port_use_count) > 2) {
> 
> This is a racy test, the count could change after the test against '2'.  It would
> be nice if there was a primitive to do the increment and test atomically, but I
> fail to see one that matches this scenerio currently.
> 
> Thank you.

I'm changing it to mutex.

Thank you,

Long