PCI/AER: Add sysfs attributes to provide AER stats and breakdown
Add sysfs attributes to provide total and breakdown of the AERs seen,
into different type of correctable, fatal and nonfatal errors:
/sys/bus/pci/devices/<dev>/aer_dev_correctable
/sys/bus/pci/devices/<dev>/aer_dev_fatal
/sys/bus/pci/devices/<dev>/aer_dev_nonfatal
Signed-off-by: Rajat Jain <rajatja@google.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats b/Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats
new file mode 100644
index 0000000..3a78429
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats
@@ -0,0 +1,94 @@
+==========================
+PCIe Device AER statistics
+==========================
+These attributes show up under all the devices that are AER capable. These
+statistical counters indicate the errors "as seen/reported by the device".
+Note that this may mean that if an endpoint is causing problems, the AER
+counters may increment at its link partner (e.g. root port) because the
+errors may be "seen" / reported by the link partner and not the
+problematic endpoint itself (which may report all counters as 0 as it never
+saw any problems).
+
+Where: /sys/bus/pci/devices/<dev>/aer_dev_correctable
+Date: July 2018
+Kernel Version: 4.19.0
+Contact: linux-pci@vger.kernel.org, rajatja@google.com
+Description: List of correctable errors seen and reported by this
+ PCI device using ERR_COR. Note that since multiple errors may
+ be reported using a single ERR_COR message, thus
+ TOTAL_ERR_COR at the end of the file may not match the actual
+ total of all the errors in the file. Sample output:
+-------------------------------------------------------------------------
+localhost /sys/devices/pci0000:00/0000:00:1c.0 # cat aer_dev_correctable
+Receiver Error 2
+Bad TLP 0
+Bad DLLP 0
+RELAY_NUM Rollover 0
+Replay Timer Timeout 0
+Advisory Non-Fatal 0
+Corrected Internal Error 0
+Header Log Overflow 0
+TOTAL_ERR_COR 2
+-------------------------------------------------------------------------
+
+Where: /sys/bus/pci/devices/<dev>/aer_dev_fatal
+Date: July 2018
+Kernel Version: 4.19.0
+Contact: linux-pci@vger.kernel.org, rajatja@google.com
+Description: List of uncorrectable fatal errors seen and reported by this
+ PCI device using ERR_FATAL. Note that since multiple errors may
+ be reported using a single ERR_FATAL message, thus
+ TOTAL_ERR_FATAL at the end of the file may not match the actual
+ total of all the errors in the file. Sample output:
+-------------------------------------------------------------------------
+localhost /sys/devices/pci0000:00/0000:00:1c.0 # cat aer_dev_fatal
+Undefined 0
+Data Link Protocol 0
+Surprise Down Error 0
+Poisoned TLP 0
+Flow Control Protocol 0
+Completion Timeout 0
+Completer Abort 0
+Unexpected Completion 0
+Receiver Overflow 0
+Malformed TLP 0
+ECRC 0
+Unsupported Request 0
+ACS Violation 0
+Uncorrectable Internal Error 0
+MC Blocked TLP 0
+AtomicOp Egress Blocked 0
+TLP Prefix Blocked Error 0
+TOTAL_ERR_FATAL 0
+-------------------------------------------------------------------------
+
+Where: /sys/bus/pci/devices/<dev>/aer_dev_nonfatal
+Date: July 2018
+Kernel Version: 4.19.0
+Contact: linux-pci@vger.kernel.org, rajatja@google.com
+Description: List of uncorrectable nonfatal errors seen and reported by this
+ PCI device using ERR_NONFATAL. Note that since multiple errors
+ may be reported using a single ERR_FATAL message, thus
+ TOTAL_ERR_NONFATAL at the end of the file may not match the
+ actual total of all the errors in the file. Sample output:
+-------------------------------------------------------------------------
+localhost /sys/devices/pci0000:00/0000:00:1c.0 # cat aer_dev_nonfatal
+Undefined 0
+Data Link Protocol 0
+Surprise Down Error 0
+Poisoned TLP 0
+Flow Control Protocol 0
+Completion Timeout 0
+Completer Abort 0
+Unexpected Completion 0
+Receiver Overflow 0
+Malformed TLP 0
+ECRC 0
+Unsupported Request 0
+ACS Violation 0
+Uncorrectable Internal Error 0
+MC Blocked TLP 0
+AtomicOp Egress Blocked 0
+TLP Prefix Blocked Error 0
+TOTAL_ERR_NONFATAL 0
+-------------------------------------------------------------------------
diff --git a/Documentation/PCI/pcieaer-howto.txt b/Documentation/PCI/pcieaer-howto.txt
index acd0ddd..48ce790 100644
--- a/Documentation/PCI/pcieaer-howto.txt
+++ b/Documentation/PCI/pcieaer-howto.txt
@@ -73,6 +73,11 @@
the error message to root port. Pls. refer to pci express specs for
other fields.
+2.4 AER Statistics / Counters
+
+When PCIe AER errors are captured, the counters / statistics are also exposed
+in the form of sysfs attributes which are documented at
+Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats
3. Developer Guide