Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> writes: > [...] >> The point is to provide a way to dynamically enable code at runtime >> without noticeable performance impact on the system. > > Quite frankly, maybe I'm a bit dense, but why don't you just recompile the > whole original function (at run-time), load that new version of a function > as a mini-module, and then insert a marker at the top of the old function > that just does a "jmp replacementfunction". [...] You mentioned possible solutions to some of the problems this ambitious an approach would cause. Here are a few more complications: - instrumenting inlined functions - proper sharing of static function data amongst multiple live copies of same function - unknown implications of violating long-standing assumptions about functions not changing addresses - interaction with other code modification machinery (kprobes, ...) - necessity to carry kernel sources & compilers on machines; slow marker activation - FChE -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
