Re: [PATCH 7/9] aacraid: use scsi_host_busy_iter() in aac_wait_for_io_completion()

Bart Van Assche
2019-11-18T23:05:42Z

On 11/18/19 1:22 AM, Hannes Reinecke wrote:
> Use the midlayer helper function to traverse outstanding commands.
>
> 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/comminit.c | 30 +++++++++++++-----------------
> 1 file changed, 13 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/scsi/aacraid/comminit.c b/drivers/scsi/aacraid/comminit.c
> index f75878d773cf..89c0ca339ef5 100644
> --- a/drivers/scsi/aacraid/comminit.c
> +++ b/drivers/scsi/aacraid/comminit.c
> @@ -272,29 +272,25 @@ static void aac_queue_init(struct aac_dev * dev, struct aac_queue * q, u32 *mem,
> q->entries = qsize;
> }
>
> +static bool wait_for_io_iter(struct scsi_cmnd *cmd, void *data, bool reserved)
> +{
> + int *active = data;
> +
> + if (cmd->SCp.phase == AAC_OWNER_FIRMWARE)
> + *active = 1;
> + return true;
> +}
> +
> +/* scsi_block_requests() has been called, so no new request can be issued */
> static void aac_wait_for_io_completion(struct aac_dev *aac)
> {
> - unsigned long flagv = 0;
> - int i = 0;
> + int i;
>
> for (i = 60; i; --i) {
> - struct scsi_device *dev;
> - struct scsi_cmnd *command;
> int active = 0;
>
> - __shost_for_each_device(dev, aac->scsi_host_ptr) {
> - spin_lock_irqsave(&dev->list_lock, flagv);
> - list_for_each_entry(command, &dev->cmd_list, list) {
> - if (command->SCp.phase == AAC_OWNER_FIRMWARE) {
> - active++;
> - break;
> - }
> - }
> - spin_unlock_irqrestore(&dev->list_lock, flagv);
> - if (active)
> - break;
> -
> - }
> + scsi_host_busy_iter(aac->scsi_host_ptr,
> + wait_for_io_iter, &active);
> /*
> * We can exit If all the commands are complete
> */

Would using scsi_device_quiesce() and scsi_device_resume() allow to
eliminate the busy-waiting loop from the aacraid driver?

Thanks,

Bart.