Re: [PATCH rev.2 0/6] ACPI: Change the ACPI namespace scanning codeordering

From: Yijing Wang
Date: Fri Dec 14 2012 - 04:56:51 EST


On 2012/12/14 6:15, Rafael J. Wysocki wrote:
> Hi All,
>
> On Sunday, December 09, 2012 11:58:42 PM Rafael J. Wysocki wrote:
>> Hi,
>>
>> The following patches change the ordering of the ACPI namespace scanning code
>> so that all struct acpi_device objects in the given scope are registered before
>> ACPI drivers are probed against them. They also do some simplifications and
>> clarifications of the code made possible by this main change.
>>
>> This is done for three basic reasons. First, we need the boot ACPI namespace
>> scanning code to be as similar as reasonably possible to the hot-plug ACPI
>> namespace scanning code. Second, the ordering of PCI devices enumeration
>> versus ACPI-backed platform devices registration needs to be such that the PCI
>> devices in the given scope are all registered first. Finally, when we start to
>> actually manage ACPI device resources as appropriate (e.g. resolve resource
>> conflicts properly) we'll need all struct acpi_device nodes to be registered
>> before any "companion" physical nodes or ACPI drivers are bound to them.
>>
>> The patches have been tested on Toshiba Portege R500 without breaking stuff
>> (I used some additional debug code to verify that the ordering of device
>> discovery had not been modified by them), but if you see any problems with
>> them regarding hot-plug, please let me know.
>>
>> [1/6] - Separate adding ACPI device objects from probing ACPI drivers.
>> [2/6] - Change the ordering of PCI root bridge driver registration.
>> [3/6] - Make acpi_bus_add() and acpi_bus_start() visibly different.
>> [4/6] - Reduce the usage of struct acpi_bus_ops
>> [5/6] - Replace struct acpi_bus_ops with an enum type
>> [6/6] - Change the ordering of acpi_bus_check_add() to avoid unnecessary checks.
>
> The second revision is necessary to address problems found by Yijing Wang
> during testing and explained by Jiang Liu (thanks guys!).
>
> The problem is that acpi_walk_namespace() doesn't execute the pre_order_visit
> callback for the starting handle, so the callback routine has the be executed
> for it directly, if necessary.
>
> I also modified a couple of changelogs to better explain the motivation of the
> patches.
>
> Boot sequence tested on Toshiba Portege R500, but testing on systems with
> hotplug will be appreciated.

Hi rafael,
I tested this version patchset in my ia64 hotplug machine, and the result looks ok.

Thanks!
Yijing

>
> Thanks,
> Rafael
>
>


--
Thanks!
Yijing

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