Xavier to Xavier PCIe NTB comm using shared memory

Autonomous Vehicles DRIVE AGX Xavier DRIVE AGX Xavier General
1

Please provide the following info (check/uncheck the boxes after clicking “+ Create Topic”):
Software Version
DRIVE OS Linux 5.2.0
DRIVE OS Linux 5.2.0 and DriveWorks 3.5
NVIDIA DRIVE™ Software 10.0 (Linux)
NVIDIA DRIVE™ Software 9.0 (Linux)
other DRIVE OS version
other

Target Operating System
Linux
QNX
other

Hardware Platform
NVIDIA DRIVE™ AGX Xavier DevKit (E3550)
NVIDIA DRIVE™ AGX Pegasus DevKit (E3550)
other

SDK Manager Version
1.6.0.8170
1.5.1.7815
1.5.0.7774
other

Host Machine Version
native Ubuntu 18.04
other

Hello everyone
I have successfully followed the steps to create an NTB connection to enable Xavier-to-Xavier communication using PCIe. Currently, I have a virtual ethernet connection between two Xavier’s on the same board (Non-Crosslink comm), and since it is a virtual ethernet communication, I can transfer data between them using a standard socket.
What I would like to achieve is to create a communication between the two Xavier’s using shared memory (or in NTB driver terminology: a “Memory Window”). Most probably, I would have to use another kernel module other than the specified ntb_netdev to create a non-virtual-ethernet link, so my question is: Is there any nvidia API that allows us to share memory between Xavier’s that can be used in this case? I am trying to avoid getting to low into Linux driver/kernel module development. Any insight is greatly appreciated.

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Dear @erick.vieyra,
Are you asking to use shared memory when doing IPC across two tegras?

4

Hello @SivaRamaKrishnaNV , thanks for your reply!
And not Tegra devices, but Xavier ones. I’d like to tap into some shared memory mechanism over a non-crosslink NTB PCIe connection between to Xavier’s.

5

Dear @erick.vieyra,
I’d like to tap into some shared memory mechanism over a non-crosslink NTB PCIe connection between to Xavier’s.

This is not supported

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Thanks for your reply @SivaRamaKrishnaNV ,
My understanding is that NTB_NETDEV PCIe only supports network-like communications, thus, as you said this is not supported.
What is the procedure that I need to follow to get a faster PCIe communication between xaviers? Perhaps using another NTB Driver (like NTB_HW) ?
Thanks in advance for your reply

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The page looks to me memory window is used in NTB Client Drivers (e.g. ntb_transport) so Non-Crosslink NTB should already leverage it.