[PATCH v7 08/16] ACPI: Add post_eject to struct acpi_scan_handler for cpu hotplug

[Hanjun Guo]

On 2024/4/18 21:54, Jonathan Cameron wrote:
> From: James Morse <james.morse at arm.com>
> 
> struct acpi_scan_handler has a detach callback that is used to remove
> a driver when a bus is changed. When interacting with an eject-request,
> the detach callback is called before _EJ0.
> 
> This means the ACPI processor driver can't use _STA to determine if a
> CPU has been made not-present, or some of the other _STA bits have been
> changed. acpi_processor_remove() needs to know the value of _STA after
> _EJ0 has been called.
> 
> Add a post_eject callback to struct acpi_scan_handler. This is called
> after acpi_scan_hot_remove() has successfully called _EJ0. Because
> acpi_scan_check_and_detach() also clears the handler pointer,
> it needs to be told if the caller will go on to call
> acpi_bus_post_eject(), so that acpi_device_clear_enumerated()
> and clearing the handler pointer can be deferred.
> An extra flag is added to flags field introduced in the previous
> patch to achieve this.
> 
> Signed-off-by: James Morse <james.morse at arm.com>
> Reviewed-by: Joanthan Cameron <Jonathan.Cameron at huawei.com>
> Reviewed-by: Gavin Shan <gshan at redhat.com>
> Tested-by: Miguel Luis <miguel.luis at oracle.com>
> Tested-by: Vishnu Pajjuri <vishnu at os.amperecomputing.com>
> Tested-by: Jianyong Wu <jianyong.wu at arm.com>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron at huawei.com>

Reviewed-by: Hanjun Guo <guohanjun at huawei.com>