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

Jonathan Cameron Jonathan.Cameron at Huawei.com
Fri Apr 26 04:48:55 PDT 2024


On Thu, 18 Apr 2024 14:54:04 +0100
Jonathan Cameron <Jonathan.Cameron at huawei.com> 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>

Gavin's earlier review showed I can't type.
Fixed up by dropping this RB seeing as I signed off anyway.

> 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>
> 



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