On Wed, Jul 23, 2025 at 11:31:07AM +0800, Shuai Xue wrote: > 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 output is like below: > > $ echo 1 > /sys/kernel/debug/tracing/events/pci/pci_hp_event/enable > $ cat /sys/kernel/debug/tracing/trace_pipe > <...>-206 [001] ..... 40.373870: pci_hp_event: 0000:00:02.0 slot:10, event:LINK_DOWN > > <...>-206 [001] ..... 40.374871: pci_hp_event: 0000:00:02.0 slot:10, event:CARD_NOT_PRESENT I asked about documentation earlier [1], but didn't see any response. I think these tracepoints are important and will be widely used, so it seems like some kind of user guide would be helpful. > Suggested-by: Lukas Wunner <lukas@xxxxxxxxx> > Suggested-by: Steven Rostedt <rostedt@xxxxxxxxxxx> > Signed-off-by: Shuai Xue <xueshuai@xxxxxxxxxxxxxxxxx> > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Nit: I assume this came from the patch I had applied to pci/trace, but you shouldn't include any sign-offs from people to whom you send patches [2]. Bjorn [1] https://lore.kernel.org/all/20250717192950.GA2594528@bhelgaas/#t [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?id=v6.13#n449
