[PATCH 13/18] rpmsg: glink: Add rx done command

[sricharan@codeaurora.org (Sricharan R)]

Hi,
>> +??? /* Take it off the tree of receive intents */
>> +??? if (!intent->reuse) {
>> +??????? spin_lock(&channel->intent_lock);
>> +??????? idr_remove(&channel->liids, intent->id);
>> +??????? spin_unlock(&channel->intent_lock);
>> +??? }
>> +
>> +??? /* Schedule the sending of a rx_done indication */
>> +??? spin_lock(&channel->intent_lock);
>> +??? list_add_tail(&intent->node, &channel->done_intents);
>> +??? spin_unlock(&channel->intent_lock);
>> +
>> +??? schedule_work(&channel->intent_work);
> 
> Adding one more parallel path will hit performance, if this worker could not get CPU cycles
> or blocked by other RT or HIGH_PRIO worker on global worker pool.
 The idea is, by design to have parallel non-blocking paths for rx and tx (that is done as a
 part of rx by sending the rx_done command), otherwise trying to send the rx_done
 command in the rx isr context is a problem since the tx can wait for the FIFO space and
 in worst case, can even lead to a potential deadlock if both the local and remote try
 the same. Having said that, instead of queuing this work in to the global queue, this
 can be put in to a local glink edge owned queue (or) a threaded isr ?, downstream does the
 rx_done in a client specific worker.

Regards,
 Sricharan

-- 
"QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus