From 40dc166cb5dddbd36aa4ad11c03915ea538f5a61 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Tue, 15 Mar 2011 00:43:46 +0100 Subject: [PATCH] PM / Core: Introduce struct syscore_ops for core subsystems PM Some subsystems need to carry out suspend/resume and shutdown operations with one CPU on-line and interrupts disabled. The only way to register such operations is to define a sysdev class and a sysdev specifically for this purpose which is cumbersome and inefficient. Moreover, the arguments taken by sysdev suspend, resume and shutdown callbacks are practically never necessary. For this reason, introduce a simpler interface allowing subsystems to register operations to be executed very late during system suspend and shutdown and very early during resume in the form of strcut syscore_ops objects. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman --- drivers/base/Makefile | 2 +- drivers/base/syscore.c | 117 ++++++++++++++++++++++++++++++++++++ include/linux/syscore_ops.h | 29 +++++++++ kernel/power/hibernate.c | 9 +++ kernel/power/suspend.c | 4 ++ kernel/sys.c | 4 ++ 6 files changed, 164 insertions(+), 1 deletion(-) create mode 100644 drivers/base/syscore.c create mode 100644 include/linux/syscore_ops.h diff --git a/drivers/base/Makefile b/drivers/base/Makefile index 5f51c3b4451e..4c5701c15f53 100644 --- a/drivers/base/Makefile +++ b/drivers/base/Makefile @@ -1,6 +1,6 @@ # Makefile for the Linux device tree -obj-y := core.o sys.o bus.o dd.o \ +obj-y := core.o sys.o bus.o dd.o syscore.o \ driver.o class.o platform.o \ cpu.o firmware.o init.o map.o devres.o \ attribute_container.o transport_class.o diff --git a/drivers/base/syscore.c b/drivers/base/syscore.c new file mode 100644 index 000000000000..90af2943f9e4 --- /dev/null +++ b/drivers/base/syscore.c @@ -0,0 +1,117 @@ +/* + * syscore.c - Execution of system core operations. + * + * Copyright (C) 2011 Rafael J. Wysocki , Novell Inc. + * + * This file is released under the GPLv2. + */ + +#include +#include +#include + +static LIST_HEAD(syscore_ops_list); +static DEFINE_MUTEX(syscore_ops_lock); + +/** + * register_syscore_ops - Register a set of system core operations. + * @ops: System core operations to register. + */ +void register_syscore_ops(struct syscore_ops *ops) +{ + mutex_lock(&syscore_ops_lock); + list_add_tail(&ops->node, &syscore_ops_list); + mutex_unlock(&syscore_ops_lock); +} +EXPORT_SYMBOL_GPL(register_syscore_ops); + +/** + * unregister_syscore_ops - Unregister a set of system core operations. + * @ops: System core operations to unregister. + */ +void unregister_syscore_ops(struct syscore_ops *ops) +{ + mutex_lock(&syscore_ops_lock); + list_del(&ops->node); + mutex_unlock(&syscore_ops_lock); +} +EXPORT_SYMBOL_GPL(unregister_syscore_ops); + +#ifdef CONFIG_PM_SLEEP +/** + * syscore_suspend - Execute all the registered system core suspend callbacks. + * + * This function is executed with one CPU on-line and disabled interrupts. + */ +int syscore_suspend(void) +{ + struct syscore_ops *ops; + int ret = 0; + + WARN_ONCE(!irqs_disabled(), + "Interrupts enabled before system core suspend.\n"); + + list_for_each_entry_reverse(ops, &syscore_ops_list, node) + if (ops->suspend) { + if (initcall_debug) + pr_info("PM: Calling %pF\n", ops->suspend); + ret = ops->suspend(); + if (ret) + goto err_out; + WARN_ONCE(!irqs_disabled(), + "Interrupts enabled after %pF\n", ops->suspend); + } + + return 0; + + err_out: + pr_err("PM: System core suspend callback %pF failed.\n", ops->suspend); + + list_for_each_entry_continue(ops, &syscore_ops_list, node) + if (ops->resume) + ops->resume(); + + return ret; +} + +/** + * syscore_resume - Execute all the registered system core resume callbacks. + * + * This function is executed with one CPU on-line and disabled interrupts. + */ +void syscore_resume(void) +{ + struct syscore_ops *ops; + + WARN_ONCE(!irqs_disabled(), + "Interrupts enabled before system core resume.\n"); + + list_for_each_entry(ops, &syscore_ops_list, node) + if (ops->resume) { + if (initcall_debug) + pr_info("PM: Calling %pF\n", ops->resume); + ops->resume(); + WARN_ONCE(!irqs_disabled(), + "Interrupts enabled after %pF\n", ops->resume); + } +} +#endif /* CONFIG_PM_SLEEP */ + +/** + * syscore_shutdown - Execute all the registered system core shutdown callbacks. + */ +void syscore_shutdown(void) +{ + struct syscore_ops *ops; + + mutex_lock(&syscore_ops_lock); + + list_for_each_entry_reverse(ops, &syscore_ops_list, node) + if (ops->shutdown) { + if (initcall_debug) + pr_info("PM: Calling %pF\n", ops->shutdown); + ops->shutdown(); + } + + mutex_unlock(&syscore_ops_lock); +} diff --git a/include/linux/syscore_ops.h b/include/linux/syscore_ops.h new file mode 100644 index 000000000000..27b3b0bc41a9 --- /dev/null +++ b/include/linux/syscore_ops.h @@ -0,0 +1,29 @@ +/* + * syscore_ops.h - System core operations. + * + * Copyright (C) 2011 Rafael J. Wysocki , Novell Inc. + * + * This file is released under the GPLv2. + */ + +#ifndef _LINUX_SYSCORE_OPS_H +#define _LINUX_SYSCORE_OPS_H + +#include + +struct syscore_ops { + struct list_head node; + int (*suspend)(void); + void (*resume)(void); + void (*shutdown)(void); +}; + +extern void register_syscore_ops(struct syscore_ops *ops); +extern void unregister_syscore_ops(struct syscore_ops *ops); +#ifdef CONFIG_PM_SLEEP +extern int syscore_suspend(void); +extern void syscore_resume(void); +#endif +extern void syscore_shutdown(void); + +#endif diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 1832bd264219..aeabd26e3342 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include @@ -272,6 +273,8 @@ static int create_image(int platform_mode) local_irq_disable(); error = sysdev_suspend(PMSG_FREEZE); + if (!error) + error = syscore_suspend(); if (error) { printk(KERN_ERR "PM: Some system devices failed to power down, " "aborting hibernation\n"); @@ -295,6 +298,7 @@ static int create_image(int platform_mode) } Power_up: + syscore_resume(); sysdev_resume(); /* NOTE: dpm_resume_noirq() is just a resume() for devices * that suspended with irqs off ... no overall powerup. @@ -403,6 +407,8 @@ static int resume_target_kernel(bool platform_mode) local_irq_disable(); error = sysdev_suspend(PMSG_QUIESCE); + if (!error) + error = syscore_suspend(); if (error) goto Enable_irqs; @@ -429,6 +435,7 @@ static int resume_target_kernel(bool platform_mode) restore_processor_state(); touch_softlockup_watchdog(); + syscore_resume(); sysdev_resume(); Enable_irqs: @@ -516,6 +523,7 @@ int hibernation_platform_enter(void) local_irq_disable(); sysdev_suspend(PMSG_HIBERNATE); + syscore_suspend(); if (pm_wakeup_pending()) { error = -EAGAIN; goto Power_up; @@ -526,6 +534,7 @@ int hibernation_platform_enter(void) while (1); Power_up: + syscore_resume(); sysdev_resume(); local_irq_enable(); enable_nonboot_cpus(); diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index de6f86bfa303..2814c32aed51 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include "power.h" @@ -163,11 +164,14 @@ static int suspend_enter(suspend_state_t state) BUG_ON(!irqs_disabled()); error = sysdev_suspend(PMSG_SUSPEND); + if (!error) + error = syscore_suspend(); if (!error) { if (!(suspend_test(TEST_CORE) || pm_wakeup_pending())) { error = suspend_ops->enter(state); events_check_enabled = false; } + syscore_resume(); sysdev_resume(); } diff --git a/kernel/sys.c b/kernel/sys.c index 18da702ec813..1ad48b3b9068 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include @@ -298,6 +299,7 @@ void kernel_restart_prepare(char *cmd) system_state = SYSTEM_RESTART; device_shutdown(); sysdev_shutdown(); + syscore_shutdown(); } /** @@ -336,6 +338,7 @@ void kernel_halt(void) { kernel_shutdown_prepare(SYSTEM_HALT); sysdev_shutdown(); + syscore_shutdown(); printk(KERN_EMERG "System halted.\n"); kmsg_dump(KMSG_DUMP_HALT); machine_halt(); @@ -355,6 +358,7 @@ void kernel_power_off(void) pm_power_off_prepare(); disable_nonboot_cpus(); sysdev_shutdown(); + syscore_shutdown(); printk(KERN_EMERG "Power down.\n"); kmsg_dump(KMSG_DUMP_POWEROFF); machine_power_off(); -- 2.20.1