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Age	Commit message (Collapse)	Author
2025-12-23	PCI: trace: Add RAS tracepoint to monitor link speed changes	Shuai Xue
	PCIe link speed degradation directly impacts system performance and often indicates hardware issues such as faulty devices, physical layer problems, or configuration errors. To this end, add a RAS tracepoint to monitor link speed changes, enabling proactive health checks and diagnostic analysis. The following output is generated when a device is hotplugged: $ echo 1 > /sys/kernel/debug/tracing/events/pci/pcie_link_event/enable $ cat /sys/kernel/debug/tracing/trace_pipe irq/51-pciehp-88 [001] ..... 381.545386: pcie_link_event: 0000:00:02.0 type:4, reason:4, cur_bus_speed:20, max_bus_speed:23, width:1, flit_mode:0, status:DLLLA Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Suggested-by: Matthew W Carlis <mattc@purestorage.com> Suggested-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://patch.msgid.link/20251210132907.58799-3-xueshuai@linux.alibaba.com
2025-12-23	PCI: trace: Add generic RAS tracepoint for hotplug event	Shuai Xue
	Hotplug events are critical indicators for analyzing hardware health, and surprise link downs can significantly impact system performance and reliability. Define a new TRACING_SYSTEM named "pci", add a generic RAS tracepoint for hotplug event to help health checks. Add enum pci_hotplug_event in include/uapi/linux/pci.h so applications like rasdaemon can register tracepoint event handlers for it. The following output is generated when a device is hotplugged: $ echo 1 > /sys/kernel/debug/tracing/events/pci/pci_hp_event/enable $ cat /sys/kernel/debug/tracing/trace_pipe irq/51-pciehp-88 [001] ..... 1311.177459: pci_hp_event: 0000:00:02.0 slot:10, event:CARD_PRESENT irq/51-pciehp-88 [001] ..... 1311.177566: pci_hp_event: 0000:00:02.0 slot:10, event:LINK_UP Suggested-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Lukas Wunner <lukas@wunner.de> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> # for trace event Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://patch.msgid.link/20251210132907.58799-2-xueshuai@linux.alibaba.com