From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.15]) (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 C9CCC303A1A; Mon, 22 Sep 2025 13:10:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758546635; cv=none; b=TyITKNRD/B1a01KcACAZExRD+9pujS37ePWR5I/abeeE5rUrp0sGDPzLv8Olj0/E9XK0tKE1TWwEVxMIkXn/obKlPoFsLBU9SYRyqnH3+4gJdilNaCvTsJO4a7WsLREGxW72gAUWIKLmosp69Uea2Uc4bHFTixbhAIxEhYRRlHY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758546635; c=relaxed/simple; bh=kr9caxoDVUMcmcbfWsVW5V+NOB4WMdmBjLFW3Q0xIfw=; h=From:Date:To:cc:Subject:In-Reply-To:Message-ID:References: MIME-Version:Content-Type; b=c03d6x6044tLXIB2UVYi/lTwPDx5mNpLyUQCgWVOQy67SK18xtjf5yzMZkTP5Cxv1wEdkQFjtAduV4oTp1ivcsPX8Tu1N5ebz9dcHku8iTYOxtppMcbeqVD5PGsiTZ0gdhNggLjnVj99XFsGPqZcPPnKpA0L2zIL8mKfBxSU7X0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=jGNrWZoM; arc=none smtp.client-ip=198.175.65.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="jGNrWZoM" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1758546633; x=1790082633; h=from:date:to:cc:subject:in-reply-to:message-id: references:mime-version; bh=kr9caxoDVUMcmcbfWsVW5V+NOB4WMdmBjLFW3Q0xIfw=; b=jGNrWZoMDoxgi49oF+DC1NdHEp5J06I6sqfk47eOh/YEYOYbxi/i8HLP P8YERdYCCJfvyDAoVzOR7wPuDyesmryP9WXGbiIskG8F1j3WamdZDi1XD 5fLaldh7JNiIXO2EwpCrFzYu35fZvx6Rnpqx6EORejEe7NIC2iBChsBdV OgRsFcaDcMCxrFNS23vrGikCer+A/BqtN/DfYHQPtNRWRlW97QvaJKOZG kiUahEqvCNy9Vre/1eY9vzIIZC/0L9Y8jKqRvNXRG+88pFYS59zmD2WL7 dFSseWmh1ml6WRooQ0K9gfyWFM7NWZTB1nvppZ935WQRctTa1w7zQ5ayj g==; X-CSE-ConnectionGUID: DRhmZfCGQ1Wr+VIOMvOG9Q== X-CSE-MsgGUID: pMbzP4LNTGO+Nj6WR5/X0g== X-IronPort-AV: E=McAfee;i="6800,10657,11561"; a="64447198" X-IronPort-AV: E=Sophos;i="6.18,285,1751266800"; d="scan'208";a="64447198" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa107.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2025 06:10:28 -0700 X-CSE-ConnectionGUID: e1nJN881Rfmoeio8g/7cyQ== X-CSE-MsgGUID: Cxy9WWlQRs+kZlPqDOLAXw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.18,285,1751266800"; d="scan'208";a="176052955" Received: from ijarvine-mobl1.ger.corp.intel.com (HELO localhost) ([10.245.244.150]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2025 06:10:20 -0700 From: =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= Date: Mon, 22 Sep 2025 16:10:16 +0300 (EEST) To: Shuai Xue cc: rostedt@goodmis.org, Lukas Wunner , linux-pci@vger.kernel.org, LKML , linux-edac@vger.kernel.org, linux-trace-kernel@vger.kernel.org, helgaas@kernel.org, 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 Subject: Re: [PATCH v10 1/3] PCI: trace: Add a generic RAS tracepoint for hotplug event In-Reply-To: <20250920060117.866-2-xueshuai@linux.alibaba.com> Message-ID: <6bab311a-d5ba-133c-fddd-52899959445c@linux.intel.com> References: <20250920060117.866-1-xueshuai@linux.alibaba.com> <20250920060117.866-2-xueshuai@linux.alibaba.com> Precedence: bulk X-Mailing-List: linux-edac@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII 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 > Suggested-by: Steven Rostedt > Signed-off-by: Shuai Xue > Reviewed-by: Lukas Wunner > Reviewed-by: Jonathan Cameron > --- > 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. > shpchp-objs := shpchp_core.o \ > shpchp_ctrl.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); > + } > + 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_fast_assign( > + __assign_str(port_name); > + __assign_str(slot); > + __entry->event = event; > + ), > + > + TP_printk("%s slot:%s, event:%s\n", > + __get_str(port_name), > + __get_str(slot), > + __print_symbolic(__entry->event, PCI_HOTPLUG_EVENT) > + ) > +); > + > +#endif /* _TRACE_HW_EVENT_PCI_H */ > + > +/* This part must be outside protection */ > +#include > 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 */ > -- i.