Commit bdaefbf5 authored by Santosh Nayak's avatar Santosh Nayak Committed by James Bottomley
Browse files

[SCSI] pm8001: Fix bogus interrupt state flag issue. 



Static checker is giving following warning:
" error: calling 'spin_unlock_irqrestore()' with bogus flags"

The code flow is as shown below:
process_oq() --> process_one_iomb --> mpi_sata_completion

In 'mpi_sata_completion'
the first call for 'spin_unlock_irqrestore()' is with flags=0,
which is as good as 'spin_unlock_irq()' ( unconditional interrupt
enabling).

So for better performance 'spin_unlock_irqrestore()' can be replaced
with 'spin_unlock_irq()' and 'spin_lock_irqsave()' can be replaced by
'spin_lock_irq()'.

Signed-off-by: default avatarSantosh Nayak <santoshprasadnayak@gmail.com>
Acked-by: default avatarJack Wang <jack_wang@usish.com>
Signed-off-by: default avatarJames Bottomley <JBottomley@Parallels.com>
parent cd9b3d04

drivers/scsi/pm8001/pm8001_hwi.c

+28 −30
Original line number Diff line number Diff line
@@ -2082,7 +2082,6 @@ mpi_sata_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) 
{

	struct sas_task *t;

	struct pm8001_ccb_info *ccb;

	unsigned long flags = 0;

	u32 param;

	u32 status;

	u32 tag;
@@ -2221,9 +2220,9 @@ mpi_sata_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) 
			ts->stat = SAS_QUEUE_FULL;

			pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

			mb();/*in order to force CPU ordering*/

			spin_unlock_irqrestore(&pm8001_ha->lock, flags);

			spin_unlock_irq(&pm8001_ha->lock);

			t->task_done(t);

			spin_lock_irqsave(&pm8001_ha->lock, flags);

			spin_lock_irq(&pm8001_ha->lock);

			return;

		}

		break;
@@ -2241,9 +2240,9 @@ mpi_sata_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) 
			ts->stat = SAS_QUEUE_FULL;

			pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

			mb();/*ditto*/

			spin_unlock_irqrestore(&pm8001_ha->lock, flags);

			spin_unlock_irq(&pm8001_ha->lock);

			t->task_done(t);

			spin_lock_irqsave(&pm8001_ha->lock, flags);

			spin_lock_irq(&pm8001_ha->lock);

			return;

		}

		break;
@@ -2269,9 +2268,9 @@ mpi_sata_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) 
			ts->stat = SAS_QUEUE_FULL;

			pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

			mb();/* ditto*/

			spin_unlock_irqrestore(&pm8001_ha->lock, flags);

			spin_unlock_irq(&pm8001_ha->lock);

			t->task_done(t);

			spin_lock_irqsave(&pm8001_ha->lock, flags);

			spin_lock_irq(&pm8001_ha->lock);

			return;

		}

		break;
@@ -2336,9 +2335,9 @@ mpi_sata_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) 
			ts->stat = SAS_QUEUE_FULL;

			pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

			mb();/*ditto*/

			spin_unlock_irqrestore(&pm8001_ha->lock, flags);

			spin_unlock_irq(&pm8001_ha->lock);

			t->task_done(t);

			spin_lock_irqsave(&pm8001_ha->lock, flags);

			spin_lock_irq(&pm8001_ha->lock);

			return;

		}

		break;
@@ -2360,9 +2359,9 @@ mpi_sata_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) 
			ts->stat = SAS_QUEUE_FULL;

			pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

			mb();/*ditto*/

			spin_unlock_irqrestore(&pm8001_ha->lock, flags);

			spin_unlock_irq(&pm8001_ha->lock);

			t->task_done(t);

			spin_lock_irqsave(&pm8001_ha->lock, flags);

			spin_lock_irq(&pm8001_ha->lock);

			return;

		}

		break;
@@ -2380,31 +2379,31 @@ mpi_sata_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) 
		ts->stat = SAS_DEV_NO_RESPONSE;

		break;

	}

	spin_lock_irqsave(&t->task_state_lock, flags);

	spin_lock_irq(&t->task_state_lock);

	t->task_state_flags &= ~SAS_TASK_STATE_PENDING;

	t->task_state_flags &= ~SAS_TASK_AT_INITIATOR;

	t->task_state_flags |= SAS_TASK_STATE_DONE;

	if (unlikely((t->task_state_flags & SAS_TASK_STATE_ABORTED))) {

		spin_unlock_irqrestore(&t->task_state_lock, flags);

		spin_unlock_irq(&t->task_state_lock);

		PM8001_FAIL_DBG(pm8001_ha,

			pm8001_printk("task 0x%p done with io_status 0x%x"

			" resp 0x%x stat 0x%x but aborted by upper layer!\n",

			t, status, ts->resp, ts->stat));

		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

	} else if (t->uldd_task) {

		spin_unlock_irqrestore(&t->task_state_lock, flags);

		spin_unlock_irq(&t->task_state_lock);

		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

		mb();/* ditto */

		spin_unlock_irqrestore(&pm8001_ha->lock, flags);

		spin_unlock_irq(&pm8001_ha->lock);

		t->task_done(t);

		spin_lock_irqsave(&pm8001_ha->lock, flags);

		spin_lock_irq(&pm8001_ha->lock);

	} else if (!t->uldd_task) {

		spin_unlock_irqrestore(&t->task_state_lock, flags);

		spin_unlock_irq(&t->task_state_lock);

		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

		mb();/*ditto*/

		spin_unlock_irqrestore(&pm8001_ha->lock, flags);

		spin_unlock_irq(&pm8001_ha->lock);

		t->task_done(t);

		spin_lock_irqsave(&pm8001_ha->lock, flags);

		spin_lock_irq(&pm8001_ha->lock);

	}

}
@@ -2412,7 +2411,6 @@ mpi_sata_completion(struct pm8001_hba_info *pm8001_ha, void *piomb) 
static void mpi_sata_event(struct pm8001_hba_info *pm8001_ha , void *piomb)

{

	struct sas_task *t;

	unsigned long flags = 0;

	struct task_status_struct *ts;

	struct pm8001_ccb_info *ccb;

	struct pm8001_device *pm8001_dev;
@@ -2492,9 +2490,9 @@ static void mpi_sata_event(struct pm8001_hba_info *pm8001_ha , void *piomb) 
			ts->stat = SAS_QUEUE_FULL;

			pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

			mb();/*ditto*/

			spin_unlock_irqrestore(&pm8001_ha->lock, flags);

			spin_unlock_irq(&pm8001_ha->lock);

			t->task_done(t);

			spin_lock_irqsave(&pm8001_ha->lock, flags);

			spin_lock_irq(&pm8001_ha->lock);

			return;

		}

		break;
@@ -2592,31 +2590,31 @@ static void mpi_sata_event(struct pm8001_hba_info *pm8001_ha , void *piomb) 
		ts->stat = SAS_OPEN_TO;

		break;

	}

	spin_lock_irqsave(&t->task_state_lock, flags);

	spin_lock_irq(&t->task_state_lock);

	t->task_state_flags &= ~SAS_TASK_STATE_PENDING;

	t->task_state_flags &= ~SAS_TASK_AT_INITIATOR;

	t->task_state_flags |= SAS_TASK_STATE_DONE;

	if (unlikely((t->task_state_flags & SAS_TASK_STATE_ABORTED))) {

		spin_unlock_irqrestore(&t->task_state_lock, flags);

		spin_unlock_irq(&t->task_state_lock);

		PM8001_FAIL_DBG(pm8001_ha,

			pm8001_printk("task 0x%p done with io_status 0x%x"

			" resp 0x%x stat 0x%x but aborted by upper layer!\n",

			t, event, ts->resp, ts->stat));

		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

	} else if (t->uldd_task) {

		spin_unlock_irqrestore(&t->task_state_lock, flags);

		spin_unlock_irq(&t->task_state_lock);

		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

		mb();/* ditto */

		spin_unlock_irqrestore(&pm8001_ha->lock, flags);

		spin_unlock_irq(&pm8001_ha->lock);

		t->task_done(t);

		spin_lock_irqsave(&pm8001_ha->lock, flags);

		spin_lock_irq(&pm8001_ha->lock);

	} else if (!t->uldd_task) {

		spin_unlock_irqrestore(&t->task_state_lock, flags);

		spin_unlock_irq(&t->task_state_lock);

		pm8001_ccb_task_free(pm8001_ha, t, ccb, tag);

		mb();/*ditto*/

		spin_unlock_irqrestore(&pm8001_ha->lock, flags);

		spin_unlock_irq(&pm8001_ha->lock);

		t->task_done(t);

		spin_lock_irqsave(&pm8001_ha->lock, flags);

		spin_lock_irq(&pm8001_ha->lock);

	}

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE