I think it is neccessary to attach the task p to new biog.
I wanted to test my own scheduler which uses bio tracking information.
SO I tried your patch, especially, get_bio_cgroup_iocontext(), to get
the io_context from bio.
In my test, I made some threads with certain iopriorities run
concurrently. To schedule these threads based on their iopriorities,
I made BGROUP directories for each iopriorities.
e.g. /cgroup/bio/be0 ... /cgroup/bio/be7
Then, I tried to attach the processes to the appropriate groups.
But the processes stayed in the original group(id=0).
...
I am sorry but I have to leave now and I cannot come here next week.
--> I will take summer holidays.
I will reply to you later.
Thanks,
- Takuya Yoshikawa
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