Re: [PATCH v10 1/3] PCI: trace: Add a generic RAS tracepoint for hotplug event

Shuai Xue
2025-09-23T07:15:43Z

在 2025/9/23 14:46, Ilpo Järvinen 写道:
> On Tue, 23 Sep 2025, Shuai Xue wrote:
>
>>
>>
>> 在 2025/9/22 21:10, Ilpo Järvinen 写道:
>>> On Sat, 20 Sep 2025, 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 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/
>
> Yes, that's the right place to add it.
>

Thanks for confirm.
Will send a new version to fix it.

Thanks.
Shuai