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Fri, 5 Sep 2025 21:32:40 +0000 Message-ID: <67ffd6b7-55c2-4ee0-9243-44bf8336152d@intel.com> Date: Fri, 5 Sep 2025 14:32:38 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3] cpufreq: ondemand: Update the efficient idle check for Intel extended Families To: "Rafael J. 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Wysocki wrote: > > Since you are adding this #ifdef below, why don't you go a bit farther and do > >> +#ifdef CONFIG_X86 >> +#include > > static bool should_io_be_busy(void) > { > /* All Intel Family 6 and later processors have efficient idle. */ > return boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && > boot_cpu_data.x86_vfm >= INTEL_PENTIUM_PRO; > } > #else > static inline bool should_io_be_busy(void) > { > return false; > } >> +#endif >> + >> #include "cpufreq_ondemand.h" >> I am fine with this approach. Would moving the #define to the header be slightly better? Add to cpufreq_ondemand.h: #ifdef CONFIG_X86 #include bool od_should_io_be_busy(void); #else static inline bool od_should_io_be_busy(void) { return false; } #endif Then, cpufreq_ondemand.c doesn't need the #ifdefs. It can simply do: bool od_should_io_be_busy(void) { /* For Intel, Family 6 and later have an efficient idle. */ return (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && boot_cpu_data.x86_vfm >= INTEL_PENTIUM_PRO); }