From 5cbc19a983141729d716be17197028434127b376 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 2 Sep 2009 11:49:52 +0200 Subject: [PATCH] x86: Add generic aperf/mperf code Move some of the aperf/mperf code out from the cpufreq driver thingy so that other people can enjoy it too. Cc: H. Peter Anvin Cc: Venkatesh Pallipadi Cc: Yanmin Cc: Dave Jones Cc: Len Brown Cc: Yinghai Lu Cc: cpufreq@vger.kernel.org Signed-off-by: Peter Zijlstra LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/include/asm/processor.h | 30 ++++++++ arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c | 79 +++------------------- 2 files changed, 39 insertions(+), 70 deletions(-) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index e08ea043e085..4ae2ccfed638 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -27,6 +27,7 @@ struct mm_struct; #include #include #include +#include #include /* @@ -1020,4 +1021,33 @@ extern void start_thread(struct pt_regs *regs, unsigned long new_ip, extern int get_tsc_mode(unsigned long adr); extern int set_tsc_mode(unsigned int val); +struct aperfmperf { + u64 aperf, mperf; +}; + +static inline void get_aperfmperf(struct aperfmperf *am) +{ + WARN_ON_ONCE(!boot_cpu_has(X86_FEATURE_APERFMPERF)); + + rdmsrl(MSR_IA32_APERF, am->aperf); + rdmsrl(MSR_IA32_MPERF, am->mperf); +} + +#define APERFMPERF_SHIFT 10 + +static inline +unsigned long calc_aperfmperf_ratio(struct aperfmperf *old, + struct aperfmperf *new) +{ + u64 aperf = new->aperf - old->aperf; + u64 mperf = new->mperf - old->mperf; + unsigned long ratio = aperf; + + mperf >>= APERFMPERF_SHIFT; + if (mperf) + ratio = div64_u64(aperf, mperf); + + return ratio; +} + #endif /* _ASM_X86_PROCESSOR_H */ diff --git a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c index 509e6a7db719..4109679863c1 100644 --- a/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -70,11 +70,7 @@ struct acpi_cpufreq_data { static DEFINE_PER_CPU(struct acpi_cpufreq_data *, drv_data); -struct acpi_msr_data { - u64 saved_aperf, saved_mperf; -}; - -static DEFINE_PER_CPU(struct acpi_msr_data, msr_data); +static DEFINE_PER_CPU(struct aperfmperf, old_perf); DEFINE_TRACE(power_mark); @@ -243,23 +239,12 @@ static u32 get_cur_val(const struct cpumask *mask) return cmd.val; } -struct perf_pair { - union { - struct { - u32 lo; - u32 hi; - } split; - u64 whole; - } aperf, mperf; -}; - /* Called via smp_call_function_single(), on the target CPU */ static void read_measured_perf_ctrs(void *_cur) { - struct perf_pair *cur = _cur; + struct aperfmperf *am = _cur; - rdmsr(MSR_IA32_APERF, cur->aperf.split.lo, cur->aperf.split.hi); - rdmsr(MSR_IA32_MPERF, cur->mperf.split.lo, cur->mperf.split.hi); + get_aperfmperf(am); } /* @@ -278,63 +263,17 @@ static void read_measured_perf_ctrs(void *_cur) static unsigned int get_measured_perf(struct cpufreq_policy *policy, unsigned int cpu) { - struct perf_pair readin, cur; - unsigned int perf_percent; + struct aperfmperf perf; + unsigned long ratio; unsigned int retval; - if (smp_call_function_single(cpu, read_measured_perf_ctrs, &readin, 1)) + if (smp_call_function_single(cpu, read_measured_perf_ctrs, &perf, 1)) return 0; - cur.aperf.whole = readin.aperf.whole - - per_cpu(msr_data, cpu).saved_aperf; - cur.mperf.whole = readin.mperf.whole - - per_cpu(msr_data, cpu).saved_mperf; - per_cpu(msr_data, cpu).saved_aperf = readin.aperf.whole; - per_cpu(msr_data, cpu).saved_mperf = readin.mperf.whole; - -#ifdef __i386__ - /* - * We dont want to do 64 bit divide with 32 bit kernel - * Get an approximate value. Return failure in case we cannot get - * an approximate value. - */ - if (unlikely(cur.aperf.split.hi || cur.mperf.split.hi)) { - int shift_count; - u32 h; - - h = max_t(u32, cur.aperf.split.hi, cur.mperf.split.hi); - shift_count = fls(h); - - cur.aperf.whole >>= shift_count; - cur.mperf.whole >>= shift_count; - } - - if (((unsigned long)(-1) / 100) < cur.aperf.split.lo) { - int shift_count = 7; - cur.aperf.split.lo >>= shift_count; - cur.mperf.split.lo >>= shift_count; - } - - if (cur.aperf.split.lo && cur.mperf.split.lo) - perf_percent = (cur.aperf.split.lo * 100) / cur.mperf.split.lo; - else - perf_percent = 0; - -#else - if (unlikely(((unsigned long)(-1) / 100) < cur.aperf.whole)) { - int shift_count = 7; - cur.aperf.whole >>= shift_count; - cur.mperf.whole >>= shift_count; - } - - if (cur.aperf.whole && cur.mperf.whole) - perf_percent = (cur.aperf.whole * 100) / cur.mperf.whole; - else - perf_percent = 0; - -#endif + ratio = calc_aperfmperf_ratio(&per_cpu(old_perf, cpu), &perf); + per_cpu(old_perf, cpu) = perf; - retval = (policy->cpuinfo.max_freq * perf_percent) / 100; + retval = (policy->cpuinfo.max_freq * ratio) >> APERFMPERF_SHIFT; return retval; } -- 2.34.1