On 4/30/2025 2:17 AM, Ilpo Järvinen wrote:
While this is not my subsystem so don't have the final say here, you had to explain quite much to prove that (and reviewer would have to go through the same places to check). Wouldn't it be much simpler for all if all those .c files would just include <asm/msr.h> directly? No need to explain anything then. Also, similar to what you're doing for some tsc related things in this series, somebody could in the future decide that hey, these static inline functions (that use .*msr.*) belong to some other file, allowing msr.h to be removed from arch/x86/events/perf_event.h. Again, we'd need to add asm/msr.h into more .c files. This is the problem with relying on indirect includes, they create hard to track dependencies for #includes done in .h files. If we actively encourage to depend on indirect #include dependencies like that, it makes it very hard to_remove_ any #include from a header file (as you have yourself discovered).
You're right, it makes a lot of sense from maintenance point of view.
