> On Tue, Oct 29, 2024 at 04:15:33PM +0000, Luck, Tony wrote: >>>>>> - if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) >>>>>> - misc_ids = hygon_nb_misc_ids; >>>>>> + if (boot_cpu_has(X86_FEATURE_ZEN)) >>>>> >>>>> check_for_deprecated_apis: WARNING: arch/x86/kernel/amd_nb.c:395: Do not use boot_cpu_has() - use cpu_feature_enabled() instead. >>>> Do the comments in cpufeature.h need updating? It seems to recommend boot_cpu_has() in most cases and suggests using static_cpu_has() (which is used by cpu_feature_enabled()) only in fast paths. /* * Static testing of CPU features. Used the same as boot_cpu_has(). It * statically patches the target code for additional performance. Use * static_cpu_has() only in fast paths, where every cycle counts. Which * means that the boot_cpu_has() variant is already fast enough for the * majority of cases and you should stick to using it as it is generally * only two instructions: a RIP-relative MOV and a TEST. * ... */ static __always_inline bool _static_cpu_has(u16 bit) > > And if not to checkpatch, then maybe it can be included in the TIP > maintainers' handbook? That is, if others are using it or something > similar. >
