RFC: How to adjust the trace pid?

[Christian König]

Hi everybody,

in amdgpu we got the following issue which I'm seeking advise how to cleanly handle it.

We have a bunch of trace points which are related to the VM subsystem and executed in either a work item, kthread or foreign process context.

Now tracing the pid of the context which we are executing in is not really that useful, so I'm wondering if we could just overwrite the pid recorded in the trace entry?

The following patch does exactly that for the vm_grab_id() trace point, but I'm not 100% sure if that is legal or not.

Any ideas? Comments?

Thanks,
Christian.