[openib-general] Re: [PATCH] cm refcount race fix

[Michael S. Tsirkin]

Quoting r. Sean Hefty <mshefty at ichips.intel.com>:
> Subject: Re: [openib-general] Re: [PATCH] cm refcount race fix
> 
> Michael S. Tsirkin wrote:
> > static inline void cm_deref_id(struct cm_id_private *cm_id_priv)
> > {
> >+	unsigned long flags;
> >+
> >+	spin_lock_irqsave(&cm_id_priv->lock, flags);
> > 	if (atomic_dec_and_test(&cm_id_priv->refcount))
> > 		wake_up(&cm_id_priv->wait);
> >+	spin_unlock_irqrestore(&cm_id_priv->lock, flags);
> > }
> 
> Could we use atomic_dec_and_lock() instead?  This would keep refcount 
> atomic, but use a spinlock to synchronize with destruction.

I think that'd work too.

-- 
MST