fix: use fp unwinding mode when running go test#269
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LGTM overall, maybe we can change the env var we set to directly set the unwinding mode
Go does not produce .eh_frame sections needed for dwarf unwinding. In dwarf mode, perf captures a stack snapshot that we can use to fall back to frame pointer unwinding via framehop. However on arm64, the snapshot is missing a key register (x29/FP) due to Go's non-standard function calling convention, so the framehop fallback fails. Using callgraph mode fp avoids this entirely: the kernel performs the unwinding itself with full access to the stack.
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Go does not produce .eh_frame sections needed for dwarf unwinding. In dwarf mode, perf captures a stack snapshot that we can use to fall back to frame pointer unwinding via framehop. However on arm64, the snapshot is missing a key register (x29/FP) due to Go's non-standard function calling convention, so the framehop fallback fails.
Using callgraph mode fp avoids this entirely: the kernel performs the unwinding itself with full access to the stack.