From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Burakov, Anatoly" <anatoly.burakov@intel.com>
Subject: Re: [PATCH v6 2/2] eal: add synchronous multi-process
	communication
Date: Fri, 26 Jan 2018 10:31:40 +0000
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Cc: bruce.richardson@intel.com, konstantin.ananyev@intel.com,
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To: Jianfeng Tan <jianfeng.tan@intel.com>, dev@dpdk.org
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On 26-Jan-18 3:41 AM, Jianfeng Tan wrote:
> We need the synchronous way for multi-process communication,
> i.e., blockingly waiting for reply message when we send a request
> to the peer process.
> 
> We add two APIs rte_eal_mp_request() and rte_eal_mp_reply() for
> such use case. By invoking rte_eal_mp_request(), a request message
> is sent out, and then it waits there for a reply message. The caller
> can specify the timeout. And the response messages will be collected
> and returned so that the caller can decide how to translate them.
> 
> The API rte_eal_mp_reply() is always called by an mp action handler.
> Here we add another parameter for rte_eal_mp_t so that the action
> handler knows which peer address to reply.
> 
>         sender-process                receiver-process
>     ----------------------            ----------------
> 
>      thread-n
>       |_rte_eal_mp_request() ----------> mp-thread
>          |_timedwait()                    |_process_msg()
>                                             |_action()
>                                                 |_rte_eal_mp_reply()
> 	        mp_thread  <---------------------|
>                    |_process_msg()
>                       |_signal(send_thread)
>      thread-m <----------|
>       |_collect-reply
> 
>   * A secondary process is only allowed to talk to the primary process.
>   * If there are multiple secondary processes for the primary process,
>     it will send request to peer1, collect response from peer1; then
>     send request to peer2, collect response from peer2, and so on.
>   * When thread-n is sending request, thread-m of that process can send
>     request at the same time.
>   * For pair <action_name, peer>, we guarantee that only one such request
>     is on the fly.
> 
> Suggested-by: Anatoly Burakov <anatoly.burakov@intel.com>
> Suggested-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
> Reviewed-by: Anatoly Burakov <anatoly.burakov@intel.com>
> Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> ---

No further comments from me :)

-- 
Thanks,
Anatoly