From 9e541b3cee70a3bbe86b176c903c23b29fe033cd Mon Sep 17 00:00:00 2001 From: Shuai Xue Date: Wed, 10 Dec 2025 21:29:05 +0800 Subject: PCI: trace: Add generic RAS tracepoint for hotplug event MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Signed-off-by: Shuai Xue Signed-off-by: Bjorn Helgaas Reviewed-by: Lukas Wunner Reviewed-by: Jonathan Cameron Reviewed-by: Steven Rostedt (Google) # for trace event Reviewed-by: Ilpo Järvinen Link: https://patch.msgid.link/20251210132907.58799-2-xueshuai@linux.alibaba.com --- include/uapi/linux/pci.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include/uapi') diff --git a/include/uapi/linux/pci.h b/include/uapi/linux/pci.h index a769eefc5139..4f150028965d 100644 --- a/include/uapi/linux/pci.h +++ b/include/uapi/linux/pci.h @@ -39,4 +39,11 @@ #define PCIIOC_MMAP_IS_MEM (PCIIOC_BASE | 0x02) /* Set mmap state to MEM space. */ #define PCIIOC_WRITE_COMBINE (PCIIOC_BASE | 0x03) /* Enable/disable write-combining. */ +enum pci_hotplug_event { + PCI_HOTPLUG_LINK_UP, + PCI_HOTPLUG_LINK_DOWN, + PCI_HOTPLUG_CARD_PRESENT, + PCI_HOTPLUG_CARD_NOT_PRESENT, +}; + #endif /* _UAPILINUX_PCI_H */ -- cgit v1.2.3