From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/cpuidle/cpuidle-haltpoll.c | 145 +++++++++++++++++++++++++++++++++++++ 1 file changed, 145 insertions(+) create mode 100644 drivers/cpuidle/cpuidle-haltpoll.c (limited to 'drivers/cpuidle/cpuidle-haltpoll.c') diff --git a/drivers/cpuidle/cpuidle-haltpoll.c b/drivers/cpuidle/cpuidle-haltpoll.c new file mode 100644 index 000000000..d8515d5c0 --- /dev/null +++ b/drivers/cpuidle/cpuidle-haltpoll.c @@ -0,0 +1,145 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * cpuidle driver for haltpoll governor. + * + * Copyright 2019 Red Hat, Inc. and/or its affiliates. + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + * Authors: Marcelo Tosatti + */ + +#include +#include +#include +#include +#include +#include +#include + +static bool force __read_mostly; +module_param(force, bool, 0444); +MODULE_PARM_DESC(force, "Load unconditionally"); + +static struct cpuidle_device __percpu *haltpoll_cpuidle_devices; +static enum cpuhp_state haltpoll_hp_state; + +static __cpuidle int default_enter_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + if (current_clr_polling_and_test()) + return index; + + arch_cpu_idle(); + return index; +} + +static struct cpuidle_driver haltpoll_driver = { + .name = "haltpoll", + .governor = "haltpoll", + .states = { + { /* entry 0 is for polling */ }, + { + .enter = default_enter_idle, + .exit_latency = 1, + .target_residency = 1, + .power_usage = -1, + .name = "haltpoll idle", + .desc = "default architecture idle", + }, + }, + .safe_state_index = 0, + .state_count = 2, +}; + +static int haltpoll_cpu_online(unsigned int cpu) +{ + struct cpuidle_device *dev; + + dev = per_cpu_ptr(haltpoll_cpuidle_devices, cpu); + if (!dev->registered) { + dev->cpu = cpu; + if (cpuidle_register_device(dev)) { + pr_notice("cpuidle_register_device %d failed!\n", cpu); + return -EIO; + } + arch_haltpoll_enable(cpu); + } + + return 0; +} + +static int haltpoll_cpu_offline(unsigned int cpu) +{ + struct cpuidle_device *dev; + + dev = per_cpu_ptr(haltpoll_cpuidle_devices, cpu); + if (dev->registered) { + arch_haltpoll_disable(cpu); + cpuidle_unregister_device(dev); + } + + return 0; +} + +static void haltpoll_uninit(void) +{ + if (haltpoll_hp_state) + cpuhp_remove_state(haltpoll_hp_state); + cpuidle_unregister_driver(&haltpoll_driver); + + free_percpu(haltpoll_cpuidle_devices); + haltpoll_cpuidle_devices = NULL; +} + +static bool haltpoll_want(void) +{ + return kvm_para_has_hint(KVM_HINTS_REALTIME) || force; +} + +static int __init haltpoll_init(void) +{ + int ret; + struct cpuidle_driver *drv = &haltpoll_driver; + + /* Do not load haltpoll if idle= is passed */ + if (boot_option_idle_override != IDLE_NO_OVERRIDE) + return -ENODEV; + + if (!kvm_para_available() || !haltpoll_want()) + return -ENODEV; + + cpuidle_poll_state_init(drv); + + ret = cpuidle_register_driver(drv); + if (ret < 0) + return ret; + + haltpoll_cpuidle_devices = alloc_percpu(struct cpuidle_device); + if (haltpoll_cpuidle_devices == NULL) { + cpuidle_unregister_driver(drv); + return -ENOMEM; + } + + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "cpuidle/haltpoll:online", + haltpoll_cpu_online, haltpoll_cpu_offline); + if (ret < 0) { + haltpoll_uninit(); + } else { + haltpoll_hp_state = ret; + ret = 0; + } + + return ret; +} + +static void __exit haltpoll_exit(void) +{ + haltpoll_uninit(); +} + +module_init(haltpoll_init); +module_exit(haltpoll_exit); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Marcelo Tosatti "); -- cgit v1.2.3