[SCSI] remove a useless get/put_device pair in scsi_requeue_command

Avoid a spurious device get/put pair by cleaning up scsi_requeue_command
and folding scsi_unprep_request into it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Christoph Hellwig 2014-02-20 14:20:58 -08:00 committed by James Bottomley
parent 27e9e0f12a
commit 134997a041

View File

@ -75,29 +75,6 @@ struct kmem_cache *scsi_sdb_cache;
*/
#define SCSI_QUEUE_DELAY 3
/*
* Function: scsi_unprep_request()
*
* Purpose: Remove all preparation done for a request, including its
* associated scsi_cmnd, so that it can be requeued.
*
* Arguments: req - request to unprepare
*
* Lock status: Assumed that no locks are held upon entry.
*
* Returns: Nothing.
*/
static void scsi_unprep_request(struct request *req)
{
struct scsi_cmnd *cmd = req->special;
blk_unprep_request(req);
req->special = NULL;
scsi_put_command(cmd);
put_device(&cmd->device->sdev_gendev);
}
/**
* __scsi_queue_insert - private queue insertion
* @cmd: The SCSI command being requeued
@ -503,16 +480,10 @@ static void scsi_requeue_command(struct request_queue *q, struct scsi_cmnd *cmd)
struct request *req = cmd->request;
unsigned long flags;
/*
* We need to hold a reference on the device to avoid the queue being
* killed after the unlock and before scsi_run_queue is invoked which
* may happen because scsi_unprep_request() puts the command which
* releases its reference on the device.
*/
get_device(&sdev->sdev_gendev);
spin_lock_irqsave(q->queue_lock, flags);
scsi_unprep_request(req);
blk_unprep_request(req);
req->special = NULL;
scsi_put_command(cmd);
blk_requeue_request(q, req);
spin_unlock_irqrestore(q->queue_lock, flags);