diff options
| author | Hiago De Franco <hiago.franco@toradex.com> | 2025-06-02 15:00:56 -0300 |
|---|---|---|
| committer | Hiago De Franco <hiago.franco@toradex.com> | 2025-06-03 10:26:20 -0300 |
| commit | defb81960f4fcb580b75bbc207e5440dad4376d6 (patch) | |
| tree | da4539935a24104d027d92a8f9afd519f2ee625a /drivers/cpufreq/cpufreq_governor.c | |
| parent | 5a6602cc6c3204b24470b2429e658c25638b10a9 (diff) | |
| parent | 1b69a86802c7e77a7624fe4970ca7d382a785b8f (diff) | |
Merge branch '5.15-2.2.x-imx' into toradex_5.15-2.2.x-imxtoradex_5.15-2.2.x-imx
Conflicts:
drivers/tty/serial/fsl_lpuart.c
Signed-off-by: Hiago De Franco <hiago.franco@toradex.com>
Diffstat (limited to 'drivers/cpufreq/cpufreq_governor.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq_governor.c | 45 |
1 files changed, 23 insertions, 22 deletions
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c index 55c80319d268..5981e3ef9ce0 100644 --- a/drivers/cpufreq/cpufreq_governor.c +++ b/drivers/cpufreq/cpufreq_governor.c @@ -145,7 +145,23 @@ unsigned int dbs_update(struct cpufreq_policy *policy) time_elapsed = update_time - j_cdbs->prev_update_time; j_cdbs->prev_update_time = update_time; - idle_time = cur_idle_time - j_cdbs->prev_cpu_idle; + /* + * cur_idle_time could be smaller than j_cdbs->prev_cpu_idle if + * it's obtained from get_cpu_idle_time_jiffy() when NOHZ is + * off, where idle_time is calculated by the difference between + * time elapsed in jiffies and "busy time" obtained from CPU + * statistics. If a CPU is 100% busy, the time elapsed and busy + * time should grow with the same amount in two consecutive + * samples, but in practice there could be a tiny difference, + * making the accumulated idle time decrease sometimes. Hence, + * in this case, idle_time should be regarded as 0 in order to + * make the further process correct. + */ + if (cur_idle_time > j_cdbs->prev_cpu_idle) + idle_time = cur_idle_time - j_cdbs->prev_cpu_idle; + else + idle_time = 0; + j_cdbs->prev_cpu_idle = cur_idle_time; if (ignore_nice) { @@ -162,7 +178,7 @@ unsigned int dbs_update(struct cpufreq_policy *policy) * calls, so the previous load value can be used then. */ load = j_cdbs->prev_load; - } else if (unlikely((int)idle_time > 2 * sampling_rate && + } else if (unlikely(idle_time > 2 * sampling_rate && j_cdbs->prev_load)) { /* * If the CPU had gone completely idle and a task has @@ -189,30 +205,15 @@ unsigned int dbs_update(struct cpufreq_policy *policy) load = j_cdbs->prev_load; j_cdbs->prev_load = 0; } else { - if (time_elapsed >= idle_time) { + if (time_elapsed > idle_time) load = 100 * (time_elapsed - idle_time) / time_elapsed; - } else { - /* - * That can happen if idle_time is returned by - * get_cpu_idle_time_jiffy(). In that case - * idle_time is roughly equal to the difference - * between time_elapsed and "busy time" obtained - * from CPU statistics. Then, the "busy time" - * can end up being greater than time_elapsed - * (for example, if jiffies_64 and the CPU - * statistics are updated by different CPUs), - * so idle_time may in fact be negative. That - * means, though, that the CPU was busy all - * the time (on the rough average) during the - * last sampling interval and 100 can be - * returned as the load. - */ - load = (int)idle_time < 0 ? 100 : 0; - } + else + load = 0; + j_cdbs->prev_load = load; } - if (unlikely((int)idle_time > 2 * sampling_rate)) { + if (unlikely(idle_time > 2 * sampling_rate)) { unsigned int periods = idle_time / sampling_rate; if (periods < idle_periods) |