From c523c68da2117a3f9f777110839b1cf7ed7221be Mon Sep 17 00:00:00 2001 From: Ramesh Thomas Date: Thu, 26 Oct 2017 19:01:34 -0700 Subject: cpuidle: ladder: Add per CPU PM QoS resume latency support Individual CPUs may have special requirements to not enter deep idle states. For example, a CPU running real time applications would not want to enter deep idle states to avoid latency impacts. At the same time other CPUs that do not have such a requirement could allow deep idle states to save power. This was already implemented in the menu governor. Implementing similar changes in the ladder governor which gets selected when CONFIG_NO_HZ and CONFIG_NO_HZ_IDLE are not set. Refer following commits for the menu governor changes. Signed-off-by: Ramesh Thomas Signed-off-by: Rafael J. Wysocki --- drivers/cpuidle/governors/ladder.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/cpuidle/governors') diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c index ce1a2ffffb2a..1ad8745fd6d6 100644 --- a/drivers/cpuidle/governors/ladder.c +++ b/drivers/cpuidle/governors/ladder.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -67,10 +68,16 @@ static int ladder_select_state(struct cpuidle_driver *drv, struct cpuidle_device *dev) { struct ladder_device *ldev = this_cpu_ptr(&ladder_devices); + struct device *device = get_cpu_device(dev->cpu); struct ladder_device_state *last_state; int last_residency, last_idx = ldev->last_state_idx; int first_idx = drv->states[0].flags & CPUIDLE_FLAG_POLLING ? 1 : 0; int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY); + int resume_latency = dev_pm_qos_raw_read_value(device); + + if (resume_latency < latency_req && + resume_latency != PM_QOS_RESUME_LATENCY_NO_CONSTRAINT) + latency_req = resume_latency; /* Special case when user has set very strict latency requirement */ if (unlikely(latency_req == 0)) { -- cgit v1.2.3