From 93940fbdc46843cea58708bbe8dd225bd0f32e67 Mon Sep 17 00:00:00 2001 From: Christian Loehle Date: Mon, 20 Jan 2025 10:09:46 +0000 Subject: cpufreq/schedutil: Only bind threads if needed Remove the unconditional binding of sugov kthreads to the affected CPUs if the cpufreq driver indicates that updates can happen from any CPU. This allows userspace to set affinities to either save power (waking up bigger CPUs on HMP can be expensive) or increasing performance (by letting the utilized CPUs run without preemption of the sugov kthread). Signed-off-by: Christian Loehle Acked-by: Viresh Kumar Acked-by: Vincent Guittot Acked-by: Rafael J. Wysocki Acked-by: Juri Lelli Link: https://patch.msgid.link/5a8deed4-7764-4729-a9d4-9520c25fa7e8@arm.com Signed-off-by: Rafael J. Wysocki --- kernel/sched/cpufreq_schedutil.c | 6 +++++- kernel/sched/syscalls.c | 7 +++++++ 2 files changed, 12 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index a2a29e3fffca..1a19d69b91ed 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -666,7 +666,11 @@ static int sugov_kthread_create(struct sugov_policy *sg_policy) } sg_policy->thread = thread; - kthread_bind_mask(thread, policy->related_cpus); + if (policy->dvfs_possible_from_any_cpu) + set_cpus_allowed_ptr(thread, policy->related_cpus); + else + kthread_bind_mask(thread, policy->related_cpus); + init_irq_work(&sg_policy->irq_work, sugov_irq_work); mutex_init(&sg_policy->work_lock); diff --git a/kernel/sched/syscalls.c b/kernel/sched/syscalls.c index 149e2c8036d3..456d339be98f 100644 --- a/kernel/sched/syscalls.c +++ b/kernel/sched/syscalls.c @@ -1129,6 +1129,13 @@ int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask) if (!task_has_dl_policy(p) || !dl_bandwidth_enabled()) return 0; + /* + * The special/sugov task isn't part of regular bandwidth/admission + * control so let userspace change affinities. + */ + if (dl_entity_is_special(&p->dl)) + return 0; + /* * Since bandwidth control happens on root_domain basis, * if admission test is enabled, we only admit -deadline -- cgit v1.2.3 From e20a70c572539a486dbd91b225fa6a194a5e2122 Mon Sep 17 00:00:00 2001 From: Wentao Liang Date: Sun, 19 Jan 2025 22:32:05 +0800 Subject: PM: hibernate: Add error handling for syscore_suspend() In hibernation_platform_enter(), the code did not check the return value of syscore_suspend(), potentially leading to a situation where syscore_resume() would be called even if syscore_suspend() failed. This could cause unpredictable behavior or system instability. Modify the code sequence in question to properly handle errors returned by syscore_suspend(). If an error occurs in the suspend path, the code now jumps to label 'Enable_irqs' skipping the syscore_resume() call and only enabling interrupts after setting the system state to SYSTEM_RUNNING. Fixes: 40dc166cb5dd ("PM / Core: Introduce struct syscore_ops for core subsystems PM") Signed-off-by: Wentao Liang Link: https://patch.msgid.link/20250119143205.2103-1-vulab@iscas.ac.cn [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 1f87aa01ba44..10a01af63a80 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -608,7 +608,11 @@ int hibernation_platform_enter(void) local_irq_disable(); system_state = SYSTEM_SUSPEND; - syscore_suspend(); + + error = syscore_suspend(); + if (error) + goto Enable_irqs; + if (pm_wakeup_pending()) { error = -EAGAIN; goto Power_up; @@ -620,6 +624,7 @@ int hibernation_platform_enter(void) Power_up: syscore_resume(); + Enable_irqs: system_state = SYSTEM_RUNNING; local_irq_enable(); -- cgit v1.2.3