diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/cpufreq/cpufreq_governor.c | 19 | ||||
| -rw-r--r-- | drivers/cpufreq/cpufreq_governor.h | 9 |
2 files changed, 19 insertions, 9 deletions
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c index 9004450863be..1b44496b2d2b 100644 --- a/drivers/cpufreq/cpufreq_governor.c +++ b/drivers/cpufreq/cpufreq_governor.c @@ -131,15 +131,25 @@ void dbs_check_cpu(struct dbs_data *dbs_data, int cpu) * timer would not have fired during CPU-idle periods. Hence * an unusually large 'wall_time' (as compared to the sampling * rate) indicates this scenario. + * + * prev_load can be zero in two cases and we must recalculate it + * for both cases: + * - during long idle intervals + * - explicitly set to zero */ - if (unlikely(wall_time > (2 * sampling_rate)) && - j_cdbs->copy_prev_load) { + if (unlikely(wall_time > (2 * sampling_rate) && + j_cdbs->prev_load)) { load = j_cdbs->prev_load; - j_cdbs->copy_prev_load = false; + + /* + * Perform a destructive copy, to ensure that we copy + * the previous load only once, upon the first wake-up + * from idle. + */ + j_cdbs->prev_load = 0; } else { load = 100 * (wall_time - idle_time) / wall_time; j_cdbs->prev_load = load; - j_cdbs->copy_prev_load = true; } if (load > max_load) @@ -373,7 +383,6 @@ int cpufreq_governor_dbs(struct cpufreq_policy *policy, (j_cdbs->prev_cpu_wall - j_cdbs->prev_cpu_idle); j_cdbs->prev_load = 100 * prev_load / (unsigned int) j_cdbs->prev_cpu_wall; - j_cdbs->copy_prev_load = true; if (ignore_nice) j_cdbs->prev_cpu_nice = diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h index c2a5b7e8070a..cc401d147e72 100644 --- a/drivers/cpufreq/cpufreq_governor.h +++ b/drivers/cpufreq/cpufreq_governor.h @@ -134,12 +134,13 @@ struct cpu_dbs_common_info { u64 prev_cpu_idle; u64 prev_cpu_wall; u64 prev_cpu_nice; - unsigned int prev_load; /* - * Flag to ensure that we copy the previous load only once, upon the - * first wake-up from idle. + * Used to keep track of load in the previous interval. However, when + * explicitly set to zero, it is used as a flag to ensure that we copy + * the previous load to the current interval only once, upon the first + * wake-up from idle. */ - bool copy_prev_load; + unsigned int prev_load; struct cpufreq_policy *cur_policy; struct delayed_work work; /* |