Merge tag 'pm-4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix two issues related to exposing the current CPU frequency to
  user space on x86.

  Specifics:

   - Disable interrupts around reading IA32_APERF and IA32_MPERF in
     aperfmperf_snapshot_khz() (introduced recently) to avoid excessive
     delays between the reads that may result from interrupt handling
     (Doug Smythies).

   - Fix the computation of the CPU frequency to be reported through the
     pstate_sample tracepoint in intel_pstate (Doug Smythies)"

* tag 'pm-4.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: x86: Disable interrupts during MSRs reading
  cpufreq: intel_pstate: report correct CPU frequencies during trace

diff --git a/arch/x86/kernel/cpu/aperfmperf.c b/arch/x86/kernel/cpu/aperfmperf.c
index 7cf7c70b6ef2a20483361fb8333a85ace25bf1d7..0ee83321a3136fcca7a00a3b7e6c375e7a51e13f 100644 (file)
--- a/arch/x86/kernel/cpu/aperfmperf.c
+++ b/arch/x86/kernel/cpu/aperfmperf.c
@@ -40,13 +40,16 @@ static void aperfmperf_snapshot_khz(void *dummy)
        struct aperfmperf_sample *s = this_cpu_ptr(&samples);
        ktime_t now = ktime_get();
        s64 time_delta = ktime_ms_delta(now, s->time);
+       unsigned long flags;
 
        /* Don't bother re-computing within the cache threshold time. */
        if (time_delta < APERFMPERF_CACHE_THRESHOLD_MS)
                return;
 
+       local_irq_save(flags);
        rdmsrl(MSR_IA32_APERF, aperf);
        rdmsrl(MSR_IA32_MPERF, mperf);
+       local_irq_restore(flags);
 
        aperf_delta = aperf - s->aperf;
        mperf_delta = mperf - s->mperf;

diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 0566455f233ed3cd663506321f08f7ae546862be..65ee4fcace1f260632cf53c150c3260cc27240ad 100644 (file)
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -1613,8 +1613,7 @@ static inline bool intel_pstate_sample(struct cpudata *cpu, u64 time)
 
 static inline int32_t get_avg_frequency(struct cpudata *cpu)
 {
-       return mul_ext_fp(cpu->sample.core_avg_perf,
-                         cpu->pstate.max_pstate_physical * cpu->pstate.scaling);
+       return mul_ext_fp(cpu->sample.core_avg_perf, cpu_khz);
 }
 
 static inline int32_t get_avg_pstate(struct cpudata *cpu)