Re: [PATCH 8/9] aacraid: use scsi_host_busy_iter() in get_num_of_incomplete_fibs()

Hannes Reinecke
2019-11-19T07:06:41Z

On 11/19/19 12:06 AM, Bart Van Assche wrote:
> On 11/18/19 1:22 AM, Hannes Reinecke wrote:
>> Use the scsi midlayer helper to traverse the number of outstanding
>> commands. This also eliminates the last usage for the cmd_list
>> functionality so we can drop it.
>>
>> Cc: Balsundar P <balsundar.p@microsemi.com>
>> Cc: Adaptec OEM Raid Solutions <aacraid@microsemi.com>
>> Signed-off-by: Hannes Reinecke <hare@suse.de>
>> ---
>>   drivers/scsi/aacraid/linit.c | 81
>> ++++++++++++++++++++++----------------------
>>   1 file changed, 41 insertions(+), 40 deletions(-)
>>
>> diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c
>> index ee6bc2f9b80a..db96482c4fdc 100644
>> --- a/drivers/scsi/aacraid/linit.c
>> +++ b/drivers/scsi/aacraid/linit.c
>> @@ -622,54 +622,56 @@ static int aac_ioctl(struct scsi_device *sdev,
>> unsigned int cmd,
>>       return aac_do_ioctl(dev, cmd, arg);
>>   }
>>   -static int get_num_of_incomplete_fibs(struct aac_dev *aac)
>> +struct fib_count_data {
>> +    int mlcnt;
>> +    int llcnt;
>> +    int ehcnt;
>> +    int fwcnt;
>> +    int krlcnt;
>> +};
>> +
>> +static bool fib_count_iter(struct scsi_cmnd *scmnd, void *data, bool
>> reserved)
>>   {
>> +    struct fib_count_data *fib_count = data;
>>   -    unsigned long flags;
>> -    struct scsi_device *sdev = NULL;
>> +    switch (scmnd->SCp.phase) {
>> +    case AAC_OWNER_FIRMWARE:
>> +        fib_count->fwcnt++;
>> +        break;
>> +    case AAC_OWNER_ERROR_HANDLER:
>> +        fib_count->ehcnt++;
>> +        break;
>> +    case AAC_OWNER_LOWLEVEL:
>> +        fib_count->llcnt++;
>> +        break;
>> +    case AAC_OWNER_MIDLEVEL:
>> +        fib_count->mlcnt++;
>> +        break;
>> +    default:
>> +        fib_count->krlcnt++;
>> +        break;
>> +    }
>> +    return true;
>> +}
>> +
>> +/* Called during SCSI EH, so we don't need to block requests */
>> +static int get_num_of_incomplete_fibs(struct aac_dev *aac)
>> +{
>>       struct Scsi_Host *shost = aac->scsi_host_ptr;
>> -    struct scsi_cmnd *scmnd = NULL;
>>       struct device *ctrl_dev;
>> +    struct fib_count_data fcnt = { };
>>   -    int mlcnt  = 0;
>> -    int llcnt  = 0;
>> -    int ehcnt  = 0;
>> -    int fwcnt  = 0;
>> -    int krlcnt = 0;
>> -
>> -    __shost_for_each_device(sdev, shost) {
>> -        spin_lock_irqsave(&sdev->list_lock, flags);
>> -        list_for_each_entry(scmnd, &sdev->cmd_list, list) {
>> -            switch (scmnd->SCp.phase) {
>> -            case AAC_OWNER_FIRMWARE:
>> -                fwcnt++;
>> -                break;
>> -            case AAC_OWNER_ERROR_HANDLER:
>> -                ehcnt++;
>> -                break;
>> -            case AAC_OWNER_LOWLEVEL:
>> -                llcnt++;
>> -                break;
>> -            case AAC_OWNER_MIDLEVEL:
>> -                mlcnt++;
>> -                break;
>> -            default:
>> -                krlcnt++;
>> -                break;
>> -            }
>> -        }
>> -        spin_unlock_irqrestore(&sdev->list_lock, flags);
>> -    }
>> +    scsi_host_busy_iter(shost, fib_count_iter, &fcnt);
>>         ctrl_dev = &aac->pdev->dev;
>>   -    dev_info(ctrl_dev, "outstanding cmd: midlevel-%d\n", mlcnt);
>> -    dev_info(ctrl_dev, "outstanding cmd: lowlevel-%d\n", llcnt);
>> -    dev_info(ctrl_dev, "outstanding cmd: error handler-%d\n", ehcnt);
>> -    dev_info(ctrl_dev, "outstanding cmd: firmware-%d\n", fwcnt);
>> -    dev_info(ctrl_dev, "outstanding cmd: kernel-%d\n", krlcnt);
>> +    dev_info(ctrl_dev, "outstanding cmd: midlevel-%d\n", fcnt.mlcnt);
>> +    dev_info(ctrl_dev, "outstanding cmd: lowlevel-%d\n", fcnt.llcnt);
>> +    dev_info(ctrl_dev, "outstanding cmd: error handler-%d\n",
>> fcnt.ehcnt);
>> +    dev_info(ctrl_dev, "outstanding cmd: firmware-%d\n", fcnt.fwcnt);
>> +    dev_info(ctrl_dev, "outstanding cmd: kernel-%d\n", fcnt.krlcnt);
>>   -    return mlcnt + llcnt + ehcnt + fwcnt;
>> +    return fcnt.mlcnt + fcnt.llcnt + fcnt.ehcnt + fcnt.fwcnt;
>>   }
>>     static int aac_eh_abort(struct scsi_cmnd* cmd)
>> @@ -1675,7 +1677,6 @@ static int aac_probe_one(struct pci_dev *pdev,
>> const struct pci_device_id *id)
>>       shost->irq = pdev->irq;
>>       shost->unique_id = unique_id;
>>       shost->max_cmd_len = 16;
>> -    shost->use_cmd_list = 1;
>>         if (aac_cfg_major == AAC_CHARDEV_NEEDS_REINIT)
>>           aac_init_char();
>
> Same comment here: could scsi_device_quiesce() and scsi_device_resume()
> have been used instead?
>
We don't need to.
This function is called during SCSI EH when the host is quiesced anyway.
That's what I tried to imply with the added comment on top.

Cheers,

Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
hare@suse.de +49 911 74053 688
SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 247165 (AG München), GF: Felix Imendörffer