[PATCH v2 3/5] PCI/AER: Add sysfs attributes to provide breakdown of AERs

[Rajat Jain <rajatja@google.com>]

Add sysfs attributes to provide breakdown of the AERs seen,
into different type of correctable or uncorrectable errors:

dev_breakdown_correctable
dev_breakdown_uncorrectable

Signed-off-by: Rajat Jain <rajatj@google.com>
---
v2: Use tabs instead of spaces, fix the subject, and print
    all non zero counters.

 drivers/pci/pcie/aer/aerdrv.h          |  6 ++++++
 drivers/pci/pcie/aer/aerdrv_errprint.c |  6 ++++--
 drivers/pci/pcie/aer/aerdrv_stats.c    | 28 ++++++++++++++++++++++++++
 3 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/pcie/aer/aerdrv.h b/drivers/pci/pcie/aer/aerdrv.h
index b5d5ad6f2c03..048fbd7c9633 100644
--- a/drivers/pci/pcie/aer/aerdrv.h
+++ b/drivers/pci/pcie/aer/aerdrv.h
@@ -89,6 +89,12 @@ int pci_aer_stats_init(struct pci_dev *pdev);
 void pci_aer_stats_exit(struct pci_dev *pdev);
 void pci_dev_aer_stats_incr(struct pci_dev *pdev, struct aer_err_info *info);
 
+extern const char
+*aer_correctable_error_string[AER_MAX_TYPEOF_CORRECTABLE_ERRS];
+
+extern const char
+*aer_uncorrectable_error_string[AER_MAX_TYPEOF_UNCORRECTABLE_ERRS];
+
 #ifdef CONFIG_ACPI_APEI
 int pcie_aer_get_firmware_first(struct pci_dev *pci_dev);
 #else
diff --git a/drivers/pci/pcie/aer/aerdrv_errprint.c b/drivers/pci/pcie/aer/aerdrv_errprint.c
index 5e8b98deda08..5585f309f1a8 100644
--- a/drivers/pci/pcie/aer/aerdrv_errprint.c
+++ b/drivers/pci/pcie/aer/aerdrv_errprint.c
@@ -68,7 +68,8 @@ static const char *aer_error_layer[] = {
 	"Transaction Layer"
 };
 
-static const char *aer_correctable_error_string[] = {
+const char
+*aer_correctable_error_string[AER_MAX_TYPEOF_CORRECTABLE_ERRS] = {
 	"Receiver Error",		/* Bit Position 0	*/
 	NULL,
 	NULL,
@@ -87,7 +88,8 @@ static const char *aer_correctable_error_string[] = {
 	"Header Log Overflow",		/* Bit Position 15	*/
 };
 
-static const char *aer_uncorrectable_error_string[] = {
+const char
+*aer_uncorrectable_error_string[AER_MAX_TYPEOF_UNCORRECTABLE_ERRS] = {
 	"Undefined",			/* Bit Position 0	*/
 	NULL,
 	NULL,
diff --git a/drivers/pci/pcie/aer/aerdrv_stats.c b/drivers/pci/pcie/aer/aerdrv_stats.c
index 5555beffef2b..e47321b267f6 100644
--- a/drivers/pci/pcie/aer/aerdrv_stats.c
+++ b/drivers/pci/pcie/aer/aerdrv_stats.c
@@ -58,10 +58,38 @@ aer_stats_aggregate_attr(dev_total_cor_errs);
 aer_stats_aggregate_attr(dev_total_fatal_errs);
 aer_stats_aggregate_attr(dev_total_nonfatal_errs);
 
+#define aer_stats_breakdown_attr(field, stats_array, strings_array)	\
+	static ssize_t							\
+	field##_show(struct device *dev, struct device_attribute *attr,	\
+		     char *buf)						\
+{									\
+	unsigned int i;							\
+	char *str = buf;						\
+	struct pci_dev *pdev = to_pci_dev(dev);				\
+	u64 *stats = pdev->aer_stats->stats_array;			\
+	for (i = 0; i < ARRAY_SIZE(strings_array); i++) {		\
+		if (strings_array[i])					\
+			str += sprintf(str, "%s = 0x%llx\n",		\
+				       strings_array[i], stats[i]);	\
+		else if (stats[i])					\
+			str += sprintf(str, #stats_array "bit[%d] = 0x%llx\n",\
+				       i, stats[i]);			\
+	}								\
+	return str-buf;							\
+}									\
+static DEVICE_ATTR_RO(field)
+
+aer_stats_breakdown_attr(dev_breakdown_correctable, dev_cor_errs,
+			 aer_correctable_error_string);
+aer_stats_breakdown_attr(dev_breakdown_uncorrectable, dev_uncor_errs,
+			 aer_uncorrectable_error_string);
+
 static struct attribute *aer_stats_attrs[] __ro_after_init = {
 	&dev_attr_dev_total_cor_errs.attr,
 	&dev_attr_dev_total_fatal_errs.attr,
 	&dev_attr_dev_total_nonfatal_errs.attr,
+	&dev_attr_dev_breakdown_correctable.attr,
+	&dev_attr_dev_breakdown_uncorrectable.attr,
 	NULL
 };
 
-- 
2.17.0.441.gb46fe60e1d-goog