Re: [PATCH v2] Hard disk S3 resume time optimization

[Oliver Neukum <oneukum@suse.de>]

On Fri, 2013-08-09 at 01:09 +0000, Brandt, Todd E wrote:

>  static struct ata_force_ent *ata_force_tbl;
>  static int ata_force_tbl_size;
> +int ata_resume_status;

A single global variable for multiple ports?
 
>  static char ata_force_param_buf[PAGE_SIZE] __initdata;
>  /* param_buf is thrown away after initialization, disallow read */
> @@ -5415,6 +5416,22 @@ static int ata_port_resume(struct device *dev)
>  	return rc;
>  }
>  
> +static int ata_port_resume_async(struct device *dev)
> +{
> +	struct ata_port *ap = to_ata_port(dev);
> +
> +	ata_resume_status = 0;
> +	ata_port_request_pm(ap, PMSG_RESUME, ATA_EH_RESET,
> +		ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, &ata_resume_status);

If this ever runs in paralell it is extremely racy.

> +	if (!ata_resume_status) {
> +		pm_runtime_disable(dev);
> +		pm_runtime_set_active(dev);
> +		pm_runtime_enable(dev);
> +	}
> +
> +	return ata_resume_status;
> +}
> +


> +	req = blk_get_request(sdkp->device->request_queue, 0, __GFP_WAIT);

What happens if commands go to the device before this has finished?
Especially should it fail.

	Regards
		Oliver