Merge branch 'pci/trace'

- Add generic RAS tracepoint for hotplug events (Shuai Xue)

- Add RAS tracepoint for link speed changes (Shuai Xue)

* pci/trace:
  Documentation: tracing: Add PCI tracepoint documentation
  PCI: trace: Add RAS tracepoint to monitor link speed changes
  PCI: trace: Add generic RAS tracepoint for hotplug event

2 files changed, 136 insertions, 0 deletions

diff --git a/include/trace/events/pci.h b/include/trace/events/pci.h
new file mode 100644
index 000000000000..9a9122f62fd3
--- /dev/null
+++ b/include/trace/events/pci.h
@@ -0,0 +1,129 @@
+/* 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 <uapi/linux/pci_regs.h>
+#include <linux/tracepoint.h>
+
+#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}
+
+/*
+ * Note: For generic PCI hotplug events, we pass already-resolved strings
+ * (port_name, slot) instead of driver-specific structures like 'struct
+ * controller'.  This is because different PCI hotplug drivers (pciehp, cpqphp,
+ * ibmphp, shpchp) define their own versions of 'struct controller' with
+ * different fields and helper functions. Using driver-specific structures would
+ * make the tracepoint interface non-generic and cause compatibility issues
+ * across different drivers.
+ */
+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)
+	)
+);
+
+#define PCI_EXP_LNKSTA_LINK_STATUS_MASK (PCI_EXP_LNKSTA_LBMS | \
+					 PCI_EXP_LNKSTA_LABS | \
+					 PCI_EXP_LNKSTA_LT | \
+					 PCI_EXP_LNKSTA_DLLLA)
+
+#define LNKSTA_FLAGS					\
+	{ PCI_EXP_LNKSTA_LT,	"LT"},			\
+	{ PCI_EXP_LNKSTA_DLLLA,	"DLLLA"},		\
+	{ PCI_EXP_LNKSTA_LBMS,	"LBMS"},		\
+	{ PCI_EXP_LNKSTA_LABS,	"LABS"}
+
+TRACE_EVENT(pcie_link_event,
+
+	TP_PROTO(struct pci_bus *bus,
+		  unsigned int reason,
+		  unsigned int width,
+		  unsigned int status
+		),
+
+	TP_ARGS(bus, reason, width, status),
+
+	TP_STRUCT__entry(
+		__string(	port_name,	pci_name(bus->self))
+		__field(	unsigned int,	type		)
+		__field(	unsigned int,	reason		)
+		__field(	unsigned int,	cur_bus_speed	)
+		__field(	unsigned int,	max_bus_speed	)
+		__field(	unsigned int,	width		)
+		__field(	unsigned int,	flit_mode	)
+		__field(	unsigned int,	link_status	)
+	),
+
+	TP_fast_assign(
+		__assign_str(port_name);
+		__entry->type			= pci_pcie_type(bus->self);
+		__entry->reason			= reason;
+		__entry->cur_bus_speed		= bus->cur_bus_speed;
+		__entry->max_bus_speed		= bus->max_bus_speed;
+		__entry->width			= width;
+		__entry->flit_mode		= bus->flit_mode;
+		__entry->link_status		= status;
+	),
+
+	TP_printk("%s type:%d, reason:%d, cur_bus_speed:%d, max_bus_speed:%d, width:%u, flit_mode:%u, status:%s\n",
+		__get_str(port_name),
+		__entry->type,
+		__entry->reason,
+		__entry->cur_bus_speed,
+		__entry->max_bus_speed,
+		__entry->width,
+		__entry->flit_mode,
+		__print_flags((unsigned long)__entry->link_status, "|",
+				LNKSTA_FLAGS)
+	)
+);
+
+#endif /* _TRACE_HW_EVENT_PCI_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
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 */