Awake function call
process:echo mem > /sys/power/state
|--late_initcall_sync(software_resume)
| |--swsusp_check # Check is the image is valid of not from swsusp_resume_device device. If it is invalid, the following process will not be excuted, you can exit and proceed with the normal startup process.
| |--pm_prepare_console
| |--__pm_notifier_call_chain
| |--freeze_processes # Freeze the processes of the current user space
| |-load_image_and_restore
| | |--lock_device_hotplug
| | |--create_basic_memory_bitmaps
| | |--swsusp_read
| | |--swsusp_close
| | |--hibernation_restore # Restore from the hibernate image
| | | |--resume_target_kernel
| | |--swsusp_free
| | |--free_basic_memory_bitmaps
| | |--unlock_device_hotplug
| |--thaw_processes # Thaw the processes of the user sapce. And at this point, the process being thawed and restored is a process in Hibernate.
| |--__pm_notifier_call_chain
| |--pm_restore_console
| |--swsusp_close
