Subject: Re: [PATCH v3 1/2] cxl: Add mechanism for delivering AFU driver
 specific events
To: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>,
        Ian Munsie <imunsie@au1.ibm.com>,
        Michael Ellerman <michaele@au1.ibm.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Matt Ochs <mrochs@us.ibm.com>, Manoj Kumar <kumarmn@us.ibm.com>
References: <1457401715-26435-1-git-send-email-imunsie@au.ibm.com>
 <87a8m7iunv.fsf@vajain21.in.ibm.com>
Cc: linuxppc-dev <linuxppc-dev@ozlabs.org>,
        Michael Neuling <mikey@neuling.org>
From: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Message-ID: <56E05876.6090006@linux.vnet.ibm.com>
Date: Wed, 9 Mar 2016 18:08:06 +0100
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Hi Vaibhav,

Le 09/03/2016 15:37, Vaibhav Jain a écrit :

> I would propose these two apis.
>
> /*
> *  fetches an event from the driver event queue. NULL means that queue
> *  is empty. Can sleep if needed. The memory for cxl_event is allocated
> *  by module being called. Hence it can be potentially be larger then
> *  sizeof(struct cxl_event). Multiple calls to this should return same
> *  pointer untill ack_event is called.
> */
> struct cxl_event * fetch_event(struct cxl_context * ctx);
>
> /*
> * Returns and acknowledge the struct cxl_event * back to the driver
> * which can then free it or maybe put it back in a kmem_cache. This
> * should be called once we have completely returned the current
> * struct cxl_event from the readcall
> */
> void ack_event(struct cxl_context * ctx, struct cxl_event *);


How would you implement polling on those APIs?
How would you implement afu_read? There are several sources of events.

   Fred