Draft: create-diff-object: __patchable_function_entries section support #1415
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The __mcount_loc section contains the addresses of patchable ftrace sites which is used by the ftrace infrastructure in the kernel to create a list of tracable functions and to know where to patch to enable tracing of them. On some kernel configurations, section is called __patchable_function_entries and is generated by the compiler. Either of __mcount_loc or __patchable_function_entries is recognised by the kernel but for these configurations, use __patchable_function_entries as it is what is expected.
Note that x86_64 arch is special (of course). Unlike other arches (ppc64le and aarch64) a x86_64 kernel built with -fpatchable-function-entry will generate nops AND create rela__patchable_function_entries for functions even marked as notrace. For this arch, always create __mount_loc sections and rely on fentry relocations to indicate ftrace call sites.