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Date: Mon, 13 May 2024 22:26:29 +0200
From: Andrew Lunn <andrew@lunn.ch>
To: admiyo@os.amperecomputing.com
Cc: Sudeep Holla <sudeep.holla@arm.com>,
	Jassi Brar <jassisinghbrar@gmail.com>,
	Jeremy Kerr <jk@codeconstruct.com.au>,
	Matt Johnston <matt@codeconstruct.com.au>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Robert Moore <robert.moore@intel.com>,
	"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
	Len Brown <lenb@kernel.org>, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/3] mctp pcc: RFC Check before sending MCTP PCC response
 ACK
Message-ID: <9e893038-e78e-43d9-82b3-c95cd7b51f18@lunn.ch>
References: <20240513173546.679061-1-admiyo@os.amperecomputing.com>
 <20240513173546.679061-4-admiyo@os.amperecomputing.com>
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On Mon, May 13, 2024 at 01:35:46PM -0400, admiyo@os.amperecomputing.com wrote:
> From: Adam Young <admiyo@os.amperecomputing.com>
> 
> Type 4 PCC channels have an option to send back a response
> to the platform when they are done processing the request.
> The flag to indicate whether or not to respond is inside
> the message body, and thus is not available to the pcc
> mailbox.  Since only one message can be processed at once per
> channel, the value of this flag is checked during message processing
> and passed back via the channels global structure.
> 
> Ideally, the mailbox callback function would return a value
> indicating whether the message requires an ACK, but that
> would be a change to the mailbox API.  That would involve
> some change to all of the mailbox based drivers.

How many mailbox drivers are there?

Generally, taking the path of least resistance will cost more in the
long run. It is better to do it properly from the start.

    Andrew