Compile agent_shinjuku in raspberry pi 4 about ghost-userspace HOT 8 CLOSED

I think I may figure out the issue:)
The asm pause instruction used in enclave.cc is an X86 instruction that is not supported by aarch64.
I changed it to the yield instruction that made it passed the compile.
I'm wondering is there anyway to verify the correctness?
Bests,
John

from ghost-userspace.

Yes, that's the correct way to fix this issue. You can call a function like the following in place of asm volatile("pause"); so that the same code works for multiple architectures:

inline void Pause() {
#ifndef __GNUC__
#error "GCC is needed for the macros in the `Pause()` function."
#endif
#if defined(__x86_64__)
  asm volatile("pause");
#elif defined(__aarch64__)
  asm volatile("yield");
#elif defined(__powerpc64__)
  asm volatile("or 27,27,27");
#else
  // Do nothing.
#endif
}

Could you please clarify what you mean about verifying correctness? If you replace the pause instruction with yield for code compiled to aarch64, then you should be good.

from ghost-userspace.

Feel free to reopen if you have any additional questions.

from ghost-userspace.

Hi, Jack, @jackhumphries
Thanks for the reply, and sorry for the late reply:) Finally got time to move on to this new project. Not sure whether I should keep all my problems to one issue or not.

I'm trying to run: bazel run fifo_agent.
I have a new question about the L3 cache check in lib/Topology.c(line 311) that RPI-4B does not have an L3 cache. But the comments on this function is for the NUMA CPU. Could that be some wrong configuration on my side? If not, would you mind providing any ideas about modifying the function?

I really appreciate that!

Bests,
JOhn

from ghost-userspace.

Hi John,

No worries and feel free to open a new issue each time. That way it is easier for other people who are having the same issue to find our discussion.

The Topology class will currently fail to construct if there is no L3 cache on your machine, though I actually updated the Topology class in our internal codebase recently so that it will construct without an L3 (this should fix your issue). Let me see if we are able to prioritize getting that pushed into the open source repo. If we can't prioritize it, I'll post the patch here for you.

Jack

from ghost-userspace.

Thanks so much for helping me out!!
I will open an issue next time. Looking forward to the new patch:) Let me know if there is anything I can help.
Meanwhile, I can work on odroid n2 which is a real heterogeneous platform.
Thanks again:)

from ghost-userspace.

Hi John,

We just pushed this in commit 1c09b74. This commit includes changes to the Topology class and some tests in topology_test to test the new changes. Please let me know if this works for you.

Jack

from ghost-userspace.

Thanks, Jack!
Just test it with FIFO scheduler and hello world binary. The new patch works on the RPI4 and odroid n2:)
Bests,
John

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