Re: [PATCH] Asynchronous power handling.

[Paul Durrant <xadimgnik@xxxxxxxxx>]

On 12/03/2024 07:23, Owen Smith wrote:
> From: Martin Harvey <Martin.Harvey@xxxxxxxxxx>
>
> XenDisk requires minimal IRP_MN_SET_POWER/IRP_MN_QUERY_POWER interactions.
> No IoWorkItems are required as operations perform no significant work.
> Power handlers are is limited to tracking state changes and calling 
> PoSetPowerState.
>
> Signed-off-by: Martin Harvey <martin.harvey@xxxxxxxxxx>
>
> Refactored
> Signed-off-by: Owen Smith <owen.smith@xxxxxxxxx>
>
> ---
>   src/xendisk/fdo.c | 552 +++++++++------------------------------------
>   src/xendisk/pdo.c | 555 +++++++++-------------------------------------
>   2 files changed, 209 insertions(+), 898 deletions(-)
>
> diff --git a/src/xendisk/fdo.c b/src/xendisk/fdo.c
> index 056e24a..2e5c0de 100644
> --- a/src/xendisk/fdo.c
> +++ b/src/xendisk/fdo.c
[snip]
> @@ -1216,13 +1219,12 @@ __FdoSetDevicePower(
>             PowerActionName(PowerAction));
>   
>       if (DeviceState == __FdoGetDevicePowerState(Fdo)) {
> -        status = FdoForwardIrpSynchronously(Fdo, Irp);
> -        IoCompleteRequest(Irp, IO_NO_INCREMENT);
> -
> +        IoSkipCurrentIrpStackLocation(Irp);
> +        status = IoCallDriver(Fdo->LowerDeviceObject, Irp);
>           goto done;
>       }
>   
> -    status = (DeviceState < __FdoGetDevicePowerState(Fdo)) ?
This appears to be an unnecessary change.

> +    status = DeviceState < __FdoGetDevicePowerState(Fdo) ?
>                __FdoSetDevicePowerUp(Fdo, Irp) :
>                __FdoSetDevicePowerDown(Fdo, Irp);
>   
[snip]
> @@ -1314,13 +1318,12 @@ __FdoSetSystemPower(
>             PowerActionName(PowerAction));
>   
>       if (SystemState == __FdoGetSystemPowerState(Fdo)) {
> -        status = FdoForwardIrpSynchronously(Fdo, Irp);
> -        IoCompleteRequest(Irp, IO_NO_INCREMENT);
> -
> +        IoSkipCurrentIrpStackLocation(Irp);
> +        status = IoCallDriver(Fdo->LowerDeviceObject, Irp);
>           goto done;
>       }
>   
> -    status = (SystemState < __FdoGetSystemPowerState(Fdo)) ?
Same here.

I can drop them on commit.

Reviewed-by: Paul Durrant <paul@xxxxxxx>

> +    status = SystemState < __FdoGetSystemPowerState(Fdo) ?
>                __FdoSetSystemPowerUp(Fdo, Irp) :
>                __FdoSetSystemPowerDown(Fdo, Irp);
>