Re: [PATCH] X86/acpi: remove redundant logic of acpi memory hotadd

From: Wen Congyang
Date: Fri Dec 07 2012 - 21:28:47 EST


At 12/08/2012 06:19 AM, Rafael J. Wysocki Wrote:
> On Tuesday, December 04, 2012 01:39:54 AM Liu, Jinsong wrote:
>> Resend it, add Rafael and linux-acpi@xxxxxxxxxxxxxxx
>
> I wonder what memory hotplug people think about that.
>
> Thanks,
> Rafael
>
>
>> ===============
>> From 1d39279e45c54ce531691da5ffe261e7689dd92c Mon Sep 17 00:00:00 2001
>> From: Liu Jinsong <jinsong.liu@xxxxxxxxx>
>> Date: Wed, 14 Nov 2012 18:52:06 +0800
>> Subject: [PATCH] X86/acpi: remove redundant logic of acpi memory hotadd
>>
>> When memory hotadd, acpi_memory_enable_device has already been done
>> at drv->ops.add (acpi_memory_device_add), no need to do it again
>> at notify callback.
>>
>> At acpi_memory_enable_device, acpi_memory_get_device_resources
>> is also a redundant action, since it has been done at drv->ops.add.
>>
>> Signed-off-by: Liu Jinsong <jinsong.liu@xxxxxxxxx>
>> ---
>> drivers/acpi/acpi_memhotplug.c | 17 -----------------
>> 1 files changed, 0 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c
>> index 24c807f..a6489fd 100644
>> --- a/drivers/acpi/acpi_memhotplug.c
>> +++ b/drivers/acpi/acpi_memhotplug.c
>> @@ -220,15 +220,6 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device)
>> struct acpi_memory_info *info;
>> int node;
>>
>> -
>> - /* Get the range from the _CRS */
>> - result = acpi_memory_get_device_resources(mem_device);
>> - if (result) {
>> - printk(KERN_ERR PREFIX "get_device_resources failed\n");
>> - mem_device->state = MEMORY_INVALID_STATE;
>> - return result;
>> - }
>> -
>> node = acpi_get_node(mem_device->device->handle);
>> /*
>> * Tell the VM there is more memory here...
>> @@ -357,14 +348,6 @@ static void acpi_memory_device_notify(acpi_handle handle, u32 event, void *data)
>> break;
>> }
>>
>> - if (acpi_memory_check_device(mem_device))
>> - break;

Hmm, if acpi_memory_check_device() fails, it means the memory device disappears
I don't know if a real hardware uses this way to remove memory device.

>> -
>> - if (acpi_memory_enable_device(mem_device)) {
>> - printk(KERN_ERR PREFIX "Cannot enable memory device\n");
>> - break;
>> - }

If acpi_memory_get_device() doesn't fail, it means that the device has been managed
by this driver, so I think we can do this cleanup.

Thanks
Wen Congyang

>> -
>> ost_code = ACPI_OST_SC_SUCCESS;
>> break;
>>
>>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/