diff options
Diffstat (limited to 'drivers/cpufreq/intel_pstate.c')
| -rw-r--r-- | drivers/cpufreq/intel_pstate.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 81057e4..9ae1596 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -910,7 +910,14 @@ static inline bool intel_pstate_sample(struct cpudata *cpu, u64 time) cpu->prev_aperf = aperf; cpu->prev_mperf = mperf; cpu->prev_tsc = tsc; - return true; + /* + * First time this function is invoked in a given cycle, all of the + * previous sample data fields are equal to zero or stale and they must + * be populated with meaningful numbers for things to work, so assume + * that sample.time will always be reset before setting the utilization + * update hook and make the caller skip the sample then. + */ + return !!cpu->last_sample_time; } static inline int32_t get_avg_frequency(struct cpudata *cpu) @@ -984,8 +991,7 @@ static inline int32_t get_target_pstate_use_performance(struct cpudata *cpu) * enough period of time to adjust our busyness. */ duration_ns = cpu->sample.time - cpu->last_sample_time; - if ((s64)duration_ns > pid_params.sample_rate_ns * 3 - && cpu->last_sample_time > 0) { + if ((s64)duration_ns > pid_params.sample_rate_ns * 3) { sample_ratio = div_fp(int_tofp(pid_params.sample_rate_ns), int_tofp(duration_ns)); core_busy = mul_fp(core_busy, sample_ratio); @@ -1100,7 +1106,6 @@ static int intel_pstate_init_cpu(unsigned int cpunum) intel_pstate_get_cpu_pstates(cpu); intel_pstate_busy_pid_reset(cpu); - intel_pstate_sample(cpu, 0); cpu->update_util.func = intel_pstate_update_util; @@ -1121,9 +1126,13 @@ static unsigned int intel_pstate_get(unsigned int cpu_num) return get_avg_frequency(cpu); } -static void intel_pstate_set_update_util_hook(unsigned int cpu) +static void intel_pstate_set_update_util_hook(unsigned int cpu_num) { - cpufreq_set_update_util_data(cpu, &all_cpu_data[cpu]->update_util); + struct cpudata *cpu = all_cpu_data[cpu_num]; + + /* Prevent intel_pstate_update_util() from using stale data. */ + cpu->sample.time = 0; + cpufreq_set_update_util_data(cpu_num, &cpu->update_util); } static void intel_pstate_clear_update_util_hook(unsigned int cpu) |