在 2025/9/22 21:10, Ilpo Järvinen 写道:

quoted

On Sat, 20 Sep 2025, Shuai Xue wrote:

quoted

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>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
  drivers/pci/Makefile              |  2 +
  drivers/pci/hotplug/Makefile      |  3 +-
  drivers/pci/hotplug/pciehp_ctrl.c | 31 ++++++++++++---
  drivers/pci/trace.c               | 11 ++++++
  include/trace/events/pci.h        | 63 +++++++++++++++++++++++++++++++
  include/uapi/linux/pci.h          |  7 ++++
  6 files changed, 110 insertions(+), 7 deletions(-)
  create mode 100644 drivers/pci/trace.c
  create mode 100644 include/trace/events/pci.h

diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 67647f1880fb..bf389bc4dd3c 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile

@@ -45,3 +45,5 @@ obj-y				+= controller/
  obj-y				+= switch/
    subdir-ccflags-$(CONFIG_PCI_DEBUG) := -DDEBUG
+
+CFLAGS_trace.o := -I$(src)

diff --git a/drivers/pci/hotplug/Makefile b/drivers/pci/hotplug/Makefile
index 40aaf31fe338..d41f7050b072 100644
--- a/drivers/pci/hotplug/Makefile
+++ b/drivers/pci/hotplug/Makefile

@@ -65,7 +65,8 @@ rpadlpar_io-objs	:=	rpadlpar_core.o \
  pciehp-objs		:=	pciehp_core.o	\
  				pciehp_ctrl.o	\
  				pciehp_pci.o	\
-				pciehp_hpc.o
+				pciehp_hpc.o	\
+				../trace.o

To make it useful for any PCI tracing, not juse hotplug, this object file
should be added in drivers/pci/Makefile, not here.

Make sence. How about adding to the main CONFIG_PCI object:

diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index bf389bc4dd3c..d7f83d06351d 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile

@@ -5,7 +5,7 @@
 obj-$(CONFIG_PCI)              += access.o bus.o probe.o host-bridge.o \
                                   remove.o pci.o pci-driver.o search.o \
                                   rom.o setup-res.o irq.o vpd.o \
-                                  setup-bus.o vc.o mmap.o devres.o
+                                  setup-bus.o vc.o mmap.o devres.o trace.o

 obj-$(CONFIG_PCI)              += msi/
 obj-$(CONFIG_PCI)              += pcie/