diff options
| author |   Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2025-08-21 20:32:25 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2025-08-21 20:32:25 +0200 |
| commit | 094a7c318b29ca792fcee28e448da1ab6627ccea (patch) | |
| tree | 94d75c52729d1f3e7f160228a127d437175873ce | |
| parent | Merge tag 'linux-cpupower-6.17-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux (diff) | |
| parent | cpuidle: governors: menu: Avoid selecting states with too much latency (diff) | |
| download | wireguard-linux-094a7c318b29ca792fcee28e448da1ab6627ccea.tar.xz wireguard-linux-094a7c318b29ca792fcee28e448da1ab6627ccea.zip | |
Merge branch 'pm-cpuidle'
Merge a menu governor fix for 6.17-rc3
* pm-cpuidle:
cpuidle: governors: menu: Avoid selecting states with too much latency
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 29 |
1 files changed, 12 insertions, 17 deletions
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 81306612a5c6..b2e3d0b0a116 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -287,20 +287,15 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, return 0; } - if (tick_nohz_tick_stopped()) { - /* - * If the tick is already stopped, the cost of possible short - * idle duration misprediction is much higher, because the CPU - * may be stuck in a shallow idle state for a long time as a - * result of it. In that case say we might mispredict and use - * the known time till the closest timer event for the idle - * state selection. - */ - if (predicted_ns < TICK_NSEC) - predicted_ns = data->next_timer_ns; - } else if (latency_req > predicted_ns) { - latency_req = predicted_ns; - } + /* + * If the tick is already stopped, the cost of possible short idle + * duration misprediction is much higher, because the CPU may be stuck + * in a shallow idle state for a long time as a result of it. In that + * case, say we might mispredict and use the known time till the closest + * timer event for the idle state selection. + */ + if (tick_nohz_tick_stopped() && predicted_ns < TICK_NSEC) + predicted_ns = data->next_timer_ns; /* * Find the idle state with the lowest power while satisfying @@ -316,13 +311,15 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, if (idx == -1) idx = i; /* first enabled state */ + if (s->exit_latency_ns > latency_req) + break; + if (s->target_residency_ns > predicted_ns) { /* * Use a physical idle state, not busy polling, unless * a timer is going to trigger soon enough. */ if ((drv->states[idx].flags & CPUIDLE_FLAG_POLLING) && - s->exit_latency_ns <= latency_req && s->target_residency_ns <= data->next_timer_ns) { predicted_ns = s->target_residency_ns; idx = i; @@ -354,8 +351,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, return idx; } - if (s->exit_latency_ns > latency_req) - break; idx = i; } |