Hi felix: Thanks for your kindly help.
i still has a question, if on a pure-compute platform, which has no /dev/dri/render node, but only with a single /dev/kfd node, how the compue scenario works since that wei have no "render" fd exists? is such platfom(without render node) exists? thanks for your kindly help.! BRs zlcao. At 2024-03-06 04:43:30, "Kuehling, Felix" <[email protected]> wrote: [AMD Official Use Only - General] I already answered this question in a reply to another email that was addressed to me: The render nodes are used for CPU mapping of VRAM with mmap calls and an offset that identifies the BO. The render node also creates the GPU virtual address space that is used by KFD to create the GPU memory mappings. Applications that use both graphics and compute can share the same GPU virtual address space in this way. Zlcao, in the future, this type of question may be better addressed to a mailing list such as [email protected], instead of writing separately to different maintainers. Regards, Felix From: Deucher, Alexander <[email protected]> Sent: Tuesday, March 5, 2024 3:17 PM To:曹子龙 <[email protected]>; Kuehling, Felix <[email protected]>; Yat Sin, David <[email protected]> Subject: Re: Why has to offer "/dev/drv/render128" fd when running ROCm demo? [AMD Official Use Only - General] + Felix, David to comment. From:曹子龙 <[email protected]> Sent: Tuesday, March 5, 2024 8:46 AM To: Deucher, Alexander <[email protected]> Subject: Why has to offer "/dev/drv/render128" fd when running ROCm demo? Hi alexander.: sorry for bother. but i really need some help to deal with my puzzle. i am a freshman to AMD GPU Driver, NOW i am trying to write a simple demo to use "/dev/kfd" and do some vram alloc/free tests, but i found you must do the right "AMDKFD_IOC_ACQUIRE_VM" ioctl comamnd before you try GPU to do vram allocation and other things. from the kfd driver code,the pre-condition to do the right "AMDKFD_IOC_ACQUIRE_VM" is to offer a "/dev/drv/render128" fd to the parameters. so, why need to do this? kfd is used for compute, but "/dev/dri/render128" is specify to gfx usaged, why must open the "/dev/dri/render128" during the KFD compute scenario? thanks for your kindly help! BRs zlcao.
