Allow userspace to read/write log ratelimits per device. Create aer/ sysfs directory to store them and any future aer configs. Tested using aer-inject[1]. Configured correctable log ratelimits to 5. Sent 6 AER errors. Observed 5 errors logged while AER stats (cat /sys/bus/pci/devices/<dev>/aer_dev_correctable) shows 6. [1] https://git.kernel.org/pub/scm/linux/kernel/git/gong.chen/aer-inject.git Signed-off-by: Jon Pan-Doh <pandoh@xxxxxxxxxx> --- .../testing/sysfs-bus-pci-devices-aer_stats | 20 +++++++ Documentation/PCI/pcieaer-howto.rst | 3 ++ drivers/pci/pci-sysfs.c | 1 + drivers/pci/pci.h | 1 + drivers/pci/pcie/aer.c | 52 +++++++++++++++++++ 5 files changed, 77 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats b/Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats index d1f67bb81d5d..c1221614c079 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats +++ b/Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats @@ -117,3 +117,23 @@ Date: July 2018 KernelVersion: 4.19.0 Contact: linux-pci@xxxxxxxxxxxxxxx, rajatja@xxxxxxxxxx Description: Total number of ERR_NONFATAL messages reported to rootport. + +PCIe AER ratelimits +------------------- + +These attributes show up under all the devices that are AER capable. +Provides configurable ratelimits of logs/irq per error type. Writing a +nonzero value changes the number of errors (burst) allowed per 5 second +window before ratelimiting. Reading gets the current ratelimits. + +What: /sys/bus/pci/devices/<dev>/aer/ratelimit_cor_log +Date: March 2025 +KernelVersion: 6.15.0 +Contact: linux-pci@xxxxxxxxxxxxxxx, pandoh@xxxxxxxxxx +Description: Log ratelimit for correctable errors. + +What: /sys/bus/pci/devices/<dev>/aer/ratelimit_uncor_log +Date: March 2025 +KernelVersion: 6.15.0 +Contact: linux-pci@xxxxxxxxxxxxxxx, pandoh@xxxxxxxxxx +Description: Log ratelimit for uncorrectable errors. diff --git a/Documentation/PCI/pcieaer-howto.rst b/Documentation/PCI/pcieaer-howto.rst index 167c0b277b62..ab5b0f232204 100644 --- a/Documentation/PCI/pcieaer-howto.rst +++ b/Documentation/PCI/pcieaer-howto.rst @@ -93,6 +93,9 @@ spammy devices from flooding the console and stalling execution. Set the default ratelimit to DEFAULT_RATELIMIT_BURST over DEFAULT_RATELIMIT_INTERVAL (10 per 5 seconds). +Ratelimits are exposed in the form of sysfs attributes and configurable. +See Documentation/ABI/testing/sysfs-bus-pci-devices-aer_stats. + AER Statistics / Counters ------------------------- diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index b46ce1a2c554..16de3093294e 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1801,6 +1801,7 @@ const struct attribute_group *pci_dev_attr_groups[] = { &pcie_dev_attr_group, #ifdef CONFIG_PCIEAER &aer_stats_attr_group, + &aer_attr_group, #endif #ifdef CONFIG_PCIEASPM &aspm_ctrl_attr_group, diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 26104aee06c0..26d30a99c48b 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -887,6 +887,7 @@ void pci_no_aer(void); void pci_aer_init(struct pci_dev *dev); void pci_aer_exit(struct pci_dev *dev); extern const struct attribute_group aer_stats_attr_group; +extern const struct attribute_group aer_attr_group; void pci_aer_clear_fatal_status(struct pci_dev *dev); int pci_aer_clear_status(struct pci_dev *dev); int pci_aer_raw_clear_status(struct pci_dev *dev); diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c index c5b5381e2930..1237faee6542 100644 --- a/drivers/pci/pcie/aer.c +++ b/drivers/pci/pcie/aer.c @@ -626,6 +626,58 @@ const struct attribute_group aer_stats_attr_group = { .is_visible = aer_stats_attrs_are_visible, }; +#define aer_ratelimit_attr(name, ratelimit) \ + static ssize_t \ + name##_show(struct device *dev, struct device_attribute *attr, \ + char *buf) \ +{ \ + struct pci_dev *pdev = to_pci_dev(dev); \ + return sysfs_emit(buf, "%u errors every %u seconds\n", \ + pdev->aer_report->ratelimit.burst, \ + pdev->aer_report->ratelimit.interval / HZ); \ +} \ + \ + static ssize_t \ + name##_store(struct device *dev, struct device_attribute *attr, \ + const char *buf, size_t count) \ +{ \ + struct pci_dev *pdev = to_pci_dev(dev); \ + int burst; \ + \ + if (kstrtoint(buf, 0, &burst) < 0) \ + return -EINVAL; \ + \ + pdev->aer_report->ratelimit.burst = burst; \ + return count; \ +} \ +static DEVICE_ATTR_RW(name) + +aer_ratelimit_attr(ratelimit_cor_log, cor_log_ratelimit); +aer_ratelimit_attr(ratelimit_uncor_log, uncor_log_ratelimit); + +static struct attribute *aer_attrs[] __ro_after_init = { + &dev_attr_ratelimit_cor_log.attr, + &dev_attr_ratelimit_uncor_log.attr, + NULL +}; + +static umode_t aer_attrs_are_visible(struct kobject *kobj, + struct attribute *a, int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct pci_dev *pdev = to_pci_dev(dev); + + if (!pdev->aer_report) + return 0; + return a->mode; +} + +const struct attribute_group aer_attr_group = { + .name = "aer", + .attrs = aer_attrs, + .is_visible = aer_attrs_are_visible, +}; + void pci_dev_aer_stats_incr(struct pci_dev *pdev, struct aer_err_info *info) { unsigned long status = info->status & ~info->mask; -- 2.48.1.601.g30ceb7b040-goog
