print BPF bytecode for debugging about bpftrace HOT 5 CLOSED

Maybe the assembly output has something to do with LLVMInitializeBPFAsmPrinter() in src/ast/codegen_llvm.cpp.

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Something happens in this for loop that makes it print out the bytecode. But Idk what it is.

src/attached_probe.cpp

for (int attempt=0; attempt<3; attempt++)
  {
    progfd_ = bpf_prog_load(progtype(probe_.type), namep,
        reinterpret_cast<struct bpf_insn*>(insns), prog_len, license,
        kernel_version(attempt), log_level, log_buf, log_buf_size);
    if (progfd_ >= 0)
      break;
  }

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It's coming out of bpf_prog_load()? We can read that code, it's in bcc: https://github.com/iovisor/bcc/blob/3835b2d85e70f18eecff71c7b66d9f416ec1bcd5/src/cc/libbpf.c#L467 .. maybe we need to set log_level.

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yep. log_level is the one setting the bytecode. The problem is when I call with a -d, AttachedProbe::load_prog is not beem called. Only when I pass a -v

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We can start by increasing verbosity for -v (as Brendan suggested in the OP) and add make this work for -d as well in the future.

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