diff options
| -rw-r--r-- | drivers/cpufreq/cpufreq_conservative.c | 8 | ||||
| -rw-r--r-- | drivers/cpufreq/cpufreq_governor.c | 29 | ||||
| -rw-r--r-- | drivers/cpufreq/cpufreq_governor.h | 2 |
3 files changed, 29 insertions, 10 deletions
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index 0b32ae28ec85..02bfd46543e9 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -85,10 +85,12 @@ static unsigned int cs_dbs_update(struct cpufreq_policy *policy) freq_step = get_freq_step(cs_tuners, policy); /* - * Decrease requested_freq one freq_step for each idle period that - * we didn't update the frequency. + * Apply deferred down steps only when the policy sample load is + * below down_threshold. Otherwise, multiple deferred down steps may + * cause a net frequency decrease outside the downscaling region. */ - if (policy_dbs->idle_periods < UINT_MAX) { + if (policy_dbs->max_sample_load < cs_tuners->down_threshold && + policy_dbs->idle_periods < UINT_MAX) { unsigned int freq_steps = policy_dbs->idle_periods * freq_step; if (requested_freq > policy->min + freq_steps) diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c index 710d93ec89b5..f3bd3dbe7c41 100644 --- a/drivers/cpufreq/cpufreq_governor.c +++ b/drivers/cpufreq/cpufreq_governor.c @@ -124,7 +124,8 @@ unsigned int dbs_update(struct cpufreq_policy *policy) struct policy_dbs_info *policy_dbs = policy->governor_data; struct dbs_data *dbs_data = policy_dbs->dbs_data; unsigned int ignore_nice = dbs_data->ignore_nice_load; - unsigned int max_load = 0, idle_periods = UINT_MAX; + unsigned int max_load = 0, max_sample_load = 0; + unsigned int idle_periods = UINT_MAX; unsigned int sampling_rate, io_busy, j; u64 cur_nice; @@ -147,7 +148,7 @@ unsigned int dbs_update(struct cpufreq_policy *policy) struct cpu_dbs_info *j_cdbs = &per_cpu(cpu_dbs, j); u64 update_time, cur_idle_time; unsigned int idle_time, time_elapsed; - unsigned int load; + unsigned int load, sample_load; cur_idle_time = get_cpu_idle_time(j, &update_time, io_busy); @@ -186,6 +187,20 @@ unsigned int dbs_update(struct cpufreq_policy *policy) j_cdbs->prev_cpu_nice = cur_nice; + /* + * Compute the sample load separately from the prev_load value + * that may be reused after a long idle interval. The conservative + * governor uses it to decide whether to apply deferred down steps. + * If no time has elapsed, retain the existing behavior and use + * prev_load. + */ + if (unlikely(!time_elapsed)) + sample_load = j_cdbs->prev_load; + else if (time_elapsed > idle_time) + sample_load = 100 * (time_elapsed - idle_time) / time_elapsed; + else + sample_load = 0; + if (unlikely(!time_elapsed)) { /* * That can only happen when this function is called @@ -220,11 +235,7 @@ unsigned int dbs_update(struct cpufreq_policy *policy) load = j_cdbs->prev_load; j_cdbs->prev_load = 0; } else { - if (time_elapsed > idle_time) - load = 100 * (time_elapsed - idle_time) / time_elapsed; - else - load = 0; - + load = sample_load; j_cdbs->prev_load = load; } @@ -237,9 +248,13 @@ unsigned int dbs_update(struct cpufreq_policy *policy) if (load > max_load) max_load = load; + + if (sample_load > max_sample_load) + max_sample_load = sample_load; } policy_dbs->idle_periods = idle_periods; + policy_dbs->max_sample_load = max_sample_load; return max_load; } diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h index 73b8ed7cfaae..806d8fb4dff1 100644 --- a/drivers/cpufreq/cpufreq_governor.h +++ b/drivers/cpufreq/cpufreq_governor.h @@ -95,6 +95,8 @@ struct policy_dbs_info { /* Multiplier for increasing sample delay temporarily. */ unsigned int rate_mult; unsigned int idle_periods; /* For conservative */ + /* Maximum load from the current policy sample. */ + unsigned int max_sample_load; /* Status indicators */ bool is_shared; /* This object is used by multiple CPUs */ bool work_in_progress; /* Work is being queued up or in progress */ |