Re: [PATCH 2/8] PCI / PCIe/ AER: Introduce pci_aer_available()

On Tuesday, August 03, 2010, Rafael J. Wysocki wrote:

On Tuesday, August 03, 2010, Hidetoshi Seto wrote:

quoted

(2010/08/03 6:54), Rafael J. Wysocki wrote:

quoted

From: Rafael J. Wysocki <redacted>

Introduce a function allowing the caller to check if PCIe AER should
be enabled.

Signed-off-by: Rafael J. Wysocki <redacted>
---

(snip)

quoted

Index: linux-2.6/drivers/pci/pcie/aer/aerdrv.c
===================================================================

--- linux-2.6.orig/drivers/pci/pcie/aer/aerdrv.c
+++ linux-2.6/drivers/pci/pcie/aer/aerdrv.c

@@ -72,6 +72,11 @@ void pci_no_aer(void)
 	pcie_aer_disable = 1;	/* has priority over 'forceload' */
 }
 
+bool pci_aer_available(void)
+{
+	return !pcie_aer_disable && pci_msi_enabled();
+}
+
 static int set_device_error_reporting(struct pci_dev *dev, void *data)
 {
 	bool enable = *((bool *)data);

@@ -411,9 +416,7 @@ static void aer_error_resume(struct pci_
  */
 static int __init aer_service_init(void)
 {
-	if (pcie_aer_disable)
-		return -ENXIO;
-	if (!pci_msi_enabled())
+	if (pci_aer_available())
 		return -ENXIO;
 	return pcie_port_service_register(&aerdriver);
 }

Breaking a big lump into small pieces often makes things clear.
You should return error when AER is _NOT_ available.

if (!pci_aer_available())
	return -ENXIO;

Be careful...

Yup, sorry.

Corrected patch is appended.

Thanks,
Rafael

---
From: Rafael J. Wysocki <redacted>
Subject: PCI / PCIe/ AER: Introduce pci_aer_available()

Introduce a function allowing the caller to check whether to try to
enable PCIe AER.

Signed-off-by: Rafael J. Wysocki <redacted>
---
 drivers/pci/pci.h             |    2 ++
 drivers/pci/pcie/aer/aerdrv.c |    9 ++++++---
 2 files changed, 8 insertions(+), 3 deletions(-)

Index: linux-2.6/drivers/pci/pci.h
===================================================================

--- linux-2.6.orig/drivers/pci/pci.h
+++ linux-2.6/drivers/pci/pci.h

@@ -131,8 +131,10 @@ static inline void pci_msi_init_pci_dev(
 
 #ifdef CONFIG_PCIEAER
 void pci_no_aer(void);
+bool pci_aer_available(void);
 #else
 static inline void pci_no_aer(void) { }
+static inline bool pci_aer_available(void) { return false; }
 #endif
 
 static inline int pci_no_d1d2(struct pci_dev *dev)

Index: linux-2.6/drivers/pci/pcie/aer/aerdrv.c
===================================================================

--- linux-2.6.orig/drivers/pci/pcie/aer/aerdrv.c
+++ linux-2.6/drivers/pci/pcie/aer/aerdrv.c

@@ -72,6 +72,11 @@ void pci_no_aer(void)
 	pcie_aer_disable = 1;	/* has priority over 'forceload' */
 }
 
+bool pci_aer_available(void)
+{
+	return !pcie_aer_disable && pci_msi_enabled();
+}
+
 static int set_device_error_reporting(struct pci_dev *dev, void *data)
 {
 	bool enable = *((bool *)data);

@@ -411,9 +416,7 @@ static void aer_error_resume(struct pci_
  */
 static int __init aer_service_init(void)
 {
-	if (pcie_aer_disable)
-		return -ENXIO;
-	if (!pci_msi_enabled())
+	if (!pci_aer_available())
 		return -ENXIO;
 	return pcie_port_service_register(&aerdriver);
 }