* Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote: > I think that, if the code were sufficiently robust, it would be handy if the > unwinder displayed function arguments. DWARF can do that to a limited extent. > > That being said, having a simpler table format would probably cover most of the > use cases. I'd say that if objtool generates the kernel's debuginfo, it all becomes a kernel internal matter to a large degree: we can add function argument display support as well and see what effect it has on data structure size and complexity - it would certainly be a nice improvement in oops output to see function arguments. But it should all start from a minimum complexity step (which will be complex enough!) and the first step should be stack trace display, in a performance optimized data structure, to allow both kernel stack dumps and various tracing and other instrumentation facilities that make use of the kernel's dwarf-ish unwider as-is. The goal of this first step would be to allow x86 to drop generating the RBP frame pointer: - This shrinks kernel text and instruction count (by 1-2% IIRC), - speeds up certain code paths measurably, - plus it also allows larger functions to use one more general purpose register. ... so it's a good thing to have, if and only if the unwinder's fragility and complexity does not kill us. And much of that fragility comes from who generates the debuginfo ... Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe live-patching" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
