From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-113.freemail.mail.aliyun.com (out30-113.freemail.mail.aliyun.com [115.124.30.113]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 53F5C2C859; Wed, 15 Oct 2025 02:35:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.113 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760495745; cv=none; b=WREnkXNWetBnbLYb6Tw/MsL+DGjOO+M2DxxB7vojy2qfh0WaCrkaT+WPZfVIj8vp2pX5g8TIAjPfOOvvWbHizN7xbyjEyzY0/DPTmCgjdtkaU7nWznDnniLM4JK0v4y/Ts3vTZxrYp3vK/3fplg+1MXr46zzpFbMYqNKKdO+8is= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760495745; c=relaxed/simple; bh=+hhfMkLoMzMaCFC05rGhJGah8vukF2mAJqtg4s3GI4Y=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Vya8+TqsXkosCveSCc9OWjx9TmvkoqdJM8Kr2NpyFZtsZbQQK/Pf2H3+OTFfSEvH/BgDa/jgRyyjVxlcA0Jv+j/tHJH1NP7ro5aQcU83UO/+qKZKGmDT2STLGpJJk5D4V8Vjux5u7G4F2jhFVe/IwOBd9Ohi91aGBEJV32FSD6c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=N9xVC8VK; arc=none smtp.client-ip=115.124.30.113 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="N9xVC8VK" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1760495739; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=tFB5nfDGfzav+SVFX4uGXGTnZIQxoYbB9Vh1ZlCmm9U=; b=N9xVC8VKDNUZKS17MCkswoU60YccOK6dV8mWEuz2JzliAZDVb6jECKdTF4hCDc4jVSR50yk3AtbBI7oF3Wd/nkXwwRahVili1BYJXEVNGTMzGRXIOLj2JJmwRRwsE0Z6DHYg0+MQE7C8CWckITsUY7JXxD2ITNZEQR3Ys/O3Zx0= Received: from 30.246.161.241(mailfrom:xueshuai@linux.alibaba.com fp:SMTPD_---0WqEPCuw_1760495736 cluster:ay36) by smtp.aliyun-inc.com; Wed, 15 Oct 2025 10:35:38 +0800 Message-ID: Date: Wed, 15 Oct 2025 10:35:36 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v12 1/3] PCI: trace: Add a generic RAS tracepoint for hotplug event To: Steven Rostedt Cc: lukas@wunner.de, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-edac@vger.kernel.org, linux-trace-kernel@vger.kernel.org, helgaas@kernel.org, ilpo.jarvinen@linux.intel.com, mattc@purestorage.com, Jonathan.Cameron@huawei.com, bhelgaas@google.com, tony.luck@intel.com, bp@alien8.de, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, oleg@redhat.com, naveen@kernel.org, davem@davemloft.net, anil.s.keshavamurthy@intel.com, mark.rutland@arm.com, peterz@infradead.org, tianruidong@linux.alibaba.com References: <20251014123159.57764-1-xueshuai@linux.alibaba.com> <20251014123159.57764-2-xueshuai@linux.alibaba.com> <20251014114029.4c59bb1a@gandalf.local.home> From: Shuai Xue In-Reply-To: <20251014114029.4c59bb1a@gandalf.local.home> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit 在 2025/10/14 23:40, Steven Rostedt 写道: > On Tue, 14 Oct 2025 20:31:57 +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 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 >> Suggested-by: Steven Rostedt >> Signed-off-by: Shuai Xue >> Reviewed-by: Lukas Wunner >> Reviewed-by: Jonathan Cameron >> --- >> drivers/pci/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 ++++ >> 5 files changed, 109 insertions(+), 6 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..58a4e4ea76b0 100644 >> --- a/drivers/pci/Makefile >> +++ b/drivers/pci/Makefile >> @@ -45,3 +45,6 @@ obj-y += controller/ >> obj-y += switch/ >> >> subdir-ccflags-$(CONFIG_PCI_DEBUG) := -DDEBUG >> + >> +CFLAGS_trace.o := -I$(src) >> +obj-$(CONFIG_TRACING) += trace.o >> diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c >> index bcc938d4420f..7805f697a02c 100644 >> --- a/drivers/pci/hotplug/pciehp_ctrl.c >> +++ b/drivers/pci/hotplug/pciehp_ctrl.c >> @@ -19,6 +19,7 @@ >> #include >> #include >> #include >> +#include >> >> #include "../pci.h" >> #include "pciehp.h" >> @@ -244,12 +245,20 @@ void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events) >> case ON_STATE: >> ctrl->state = POWEROFF_STATE; >> mutex_unlock(&ctrl->state_lock); >> - if (events & PCI_EXP_SLTSTA_DLLSC) >> + if (events & PCI_EXP_SLTSTA_DLLSC) { >> ctrl_info(ctrl, "Slot(%s): Link Down\n", >> slot_name(ctrl)); >> - if (events & PCI_EXP_SLTSTA_PDC) >> + trace_pci_hp_event(pci_name(ctrl->pcie->port), >> + slot_name(ctrl), >> + PCI_HOTPLUG_LINK_DOWN); > > I know this is v12 and I don't remember if I suggested this before and you > gave me a reason already, Aha, in our previous email discussions regarding the tracepoint implementation, you provided many constructive suggestions, so I added the Suggested-by tag. Perhaps I misunderstood the meaning of Suggested-by - I will drop it. > but why not simply pass in "ctrl" and have the > TRACE_EVENT() denote the names? Sure, I will send a version. >> + } >> + if (events & PCI_EXP_SLTSTA_PDC) { >> ctrl_info(ctrl, "Slot(%s): Card not present\n", >> slot_name(ctrl)); >> + trace_pci_hp_event(pci_name(ctrl->pcie->port), >> + slot_name(ctrl), >> + PCI_HOTPLUG_CARD_NOT_PRESENT); >> + } >> pciehp_disable_slot(ctrl, SURPRISE_REMOVAL); >> break; >> default: >> @@ -269,6 +278,9 @@ void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events) >> INDICATOR_NOOP); >> ctrl_info(ctrl, "Slot(%s): Card not present\n", >> slot_name(ctrl)); >> + trace_pci_hp_event(pci_name(ctrl->pcie->port), >> + slot_name(ctrl), >> + PCI_HOTPLUG_CARD_NOT_PRESENT); >> } >> mutex_unlock(&ctrl->state_lock); >> return; >> @@ -281,12 +293,19 @@ void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events) >> case OFF_STATE: >> ctrl->state = POWERON_STATE; >> mutex_unlock(&ctrl->state_lock); >> - if (present) >> + if (present) { >> ctrl_info(ctrl, "Slot(%s): Card present\n", >> slot_name(ctrl)); >> - if (link_active) >> - ctrl_info(ctrl, "Slot(%s): Link Up\n", >> - slot_name(ctrl)); >> + trace_pci_hp_event(pci_name(ctrl->pcie->port), >> + slot_name(ctrl), >> + PCI_HOTPLUG_CARD_PRESENT); >> + } >> + if (link_active) { >> + ctrl_info(ctrl, "Slot(%s): Link Up\n", slot_name(ctrl)); >> + trace_pci_hp_event(pci_name(ctrl->pcie->port), >> + slot_name(ctrl), >> + PCI_HOTPLUG_LINK_UP); >> + } >> ctrl->request_result = pciehp_enable_slot(ctrl); >> break; >> default: >> diff --git a/drivers/pci/trace.c b/drivers/pci/trace.c >> new file mode 100644 >> index 000000000000..cf11abca8602 >> --- /dev/null >> +++ b/drivers/pci/trace.c >> @@ -0,0 +1,11 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +/* >> + * Tracepoints for PCI system >> + * >> + * Copyright (C) 2025 Alibaba Corporation >> + */ >> + >> +#include >> + >> +#define CREATE_TRACE_POINTS >> +#include >> diff --git a/include/trace/events/pci.h b/include/trace/events/pci.h >> new file mode 100644 >> index 000000000000..208609492c06 >> --- /dev/null >> +++ b/include/trace/events/pci.h >> @@ -0,0 +1,63 @@ >> +/* SPDX-License-Identifier: GPL-2.0 */ >> +#undef TRACE_SYSTEM >> +#define TRACE_SYSTEM pci >> + >> +#if !defined(_TRACE_HW_EVENT_PCI_H) || defined(TRACE_HEADER_MULTI_READ) >> +#define _TRACE_HW_EVENT_PCI_H >> + >> +#include >> + >> +#define PCI_HOTPLUG_EVENT \ >> + EM(PCI_HOTPLUG_LINK_UP, "LINK_UP") \ >> + EM(PCI_HOTPLUG_LINK_DOWN, "LINK_DOWN") \ >> + EM(PCI_HOTPLUG_CARD_PRESENT, "CARD_PRESENT") \ >> + EMe(PCI_HOTPLUG_CARD_NOT_PRESENT, "CARD_NOT_PRESENT") >> + >> +/* Enums require being exported to userspace, for user tool parsing */ >> +#undef EM >> +#undef EMe >> +#define EM(a, b) TRACE_DEFINE_ENUM(a); >> +#define EMe(a, b) TRACE_DEFINE_ENUM(a); >> + >> +PCI_HOTPLUG_EVENT >> + >> +/* >> + * Now redefine the EM() and EMe() macros to map the enums to the strings >> + * that will be printed in the output. >> + */ >> +#undef EM >> +#undef EMe >> +#define EM(a, b) {a, b}, >> +#define EMe(a, b) {a, b} >> + >> +TRACE_EVENT(pci_hp_event, >> + >> + TP_PROTO(const char *port_name, >> + const char *slot, >> + const int event), >> + >> + TP_ARGS(port_name, slot, event), >> + >> + TP_STRUCT__entry( >> + __string( port_name, port_name ) >> + __string( slot, slot ) >> + __field( int, event ) >> + ), > > TP_PROTO(struct controller *ctrl, int event), > > TP_ARGS(ctrl, event), > > TP_STRUCT__entry( > __string( port_name, pci_name(ctrl->pcie->port) ) > __string( slot, slot_name(ctrl) ) > __field( int, event ) > ), > > It would move the work out of the calling path. > I see. > -- Steve Thanks. Best Regards, Shuai