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[1/3] scsi: aacraid: Check for PCI state of device in a generic way

Message ID 20171117211455.29031-2-gpiccoli@linux.vnet.ibm.com (mailing list archive)
State Accepted
Headers show

Commit Message

Guilherme G. Piccoli Nov. 17, 2017, 9:14 p.m. UTC
Commit 16ae9dd35d37 ("scsi: aacraid: Fix for excessive prints on EEH")
introduced checks about the state of device before any PCI operations
in the driver. Basically, this prevents it to perform PCI accesses
when device is in the process of recover from a PCI error. In PowerPC,
such mechanism is called EEH, and the aforementioned commit introduced
checks that are based on EEH-specific primitives for that.

The potential problems with this approach are three: first, these checks
are "locked" to powerpc only - another archs could have error recovery
methods too, like AER in Intel. Also, the powerpc primitives perform
expensive FW accesses to validate the precise PCI state of a device.
Finally, code becomes more complicated and needs ifdef validation
based on arch config being set.

So, this patch makes use of generic PCI state checks, which are
lightweight and non-dependent of arch configs - also, it makes
the code cleaner.

Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
---
 drivers/scsi/aacraid/commsup.c | 33 ++-------------------------------
 1 file changed, 2 insertions(+), 31 deletions(-)

Comments

Dave Carroll Nov. 17, 2017, 10:54 p.m. UTC | #1
> Commit 16ae9dd35d37 ("scsi: aacraid: Fix for excessive prints on EEH")
> introduced checks about the state of device before any PCI operations
> in the driver. Basically, this prevents it to perform PCI accesses
> when device is in the process of recover from a PCI error. In PowerPC,
> such mechanism is called EEH, and the aforementioned commit introduced
> checks that are based on EEH-specific primitives for that.
> 
> The potential problems with this approach are three: first, these checks
> are "locked" to powerpc only - another archs could have error recovery
> methods too, like AER in Intel. Also, the powerpc primitives perform
> expensive FW accesses to validate the precise PCI state of a device.
> Finally, code becomes more complicated and needs ifdef validation
> based on arch config being set.
> 
> So, this patch makes use of generic PCI state checks, which are
> lightweight and non-dependent of arch configs - also, it makes
> the code cleaner.
> 
> Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
> ---

Reviewed-by: Dave Carroll <david.carroll@microsemi.com>
diff mbox

Patch

diff --git a/drivers/scsi/aacraid/commsup.c b/drivers/scsi/aacraid/commsup.c
index 525a652dab48..2abe8fd83494 100644
--- a/drivers/scsi/aacraid/commsup.c
+++ b/drivers/scsi/aacraid/commsup.c
@@ -467,35 +467,6 @@  int aac_queue_get(struct aac_dev * dev, u32 * index, u32 qid, struct hw_fib * hw
 	return 0;
 }
 
-#ifdef CONFIG_EEH
-static inline int aac_check_eeh_failure(struct aac_dev *dev)
-{
-	/* Check for an EEH failure for the given
-	 * device node. Function eeh_dev_check_failure()
-	 * returns 0 if there has not been an EEH error
-	 * otherwise returns a non-zero value.
-	 *
-	 * Need to be called before any PCI operation,
-	 * i.e.,before aac_adapter_check_health()
-	 */
-	struct eeh_dev *edev = pci_dev_to_eeh_dev(dev->pdev);
-
-	if (eeh_dev_check_failure(edev)) {
-		/* The EEH mechanisms will handle this
-		 * error and reset the device if
-		 * necessary.
-		 */
-		return 1;
-	}
-	return 0;
-}
-#else
-static inline int aac_check_eeh_failure(struct aac_dev *dev)
-{
-	return 0;
-}
-#endif
-
 /*
  *	Define the highest level of host to adapter communication routines.
  *	These routines will support host to adapter FS commuication. These
@@ -701,7 +672,7 @@  int aac_fib_send(u16 command, struct fib *fibptr, unsigned long size,
 					return -ETIMEDOUT;
 				}
 
-				if (aac_check_eeh_failure(dev))
+				if (unlikely(pci_channel_offline(dev->pdev)))
 					return -EFAULT;
 
 				if ((blink = aac_adapter_check_health(dev)) > 0) {
@@ -801,7 +772,7 @@  int aac_hba_send(u8 command, struct fib *fibptr, fib_callback callback,
 
 		spin_unlock_irqrestore(&fibptr->event_lock, flags);
 
-		if (aac_check_eeh_failure(dev))
+		if (unlikely(pci_channel_offline(dev->pdev)))
 			return -EFAULT;
 
 		fibptr->flags |= FIB_CONTEXT_FLAG_WAIT;