1 files changed, 97 insertions, 0 deletions
diff --git a/include/linux/trace.h b/include/linux/trace.h
new file mode 100644
index 000000000..2a70a4471
--- /dev/null
+++ b/include/linux/trace.h
@@ -0,0 +1,97 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_TRACE_H
+#define _LINUX_TRACE_H
+
+#define TRACE_EXPORT_FUNCTION	BIT(0)
+#define TRACE_EXPORT_EVENT	BIT(1)
+#define TRACE_EXPORT_MARKER	BIT(2)
+
+/*
+ * The trace export - an export of Ftrace output. The trace_export
+ * can process traces and export them to a registered destination as
+ * an addition to the current only output of Ftrace - i.e. ring buffer.
+ *
+ * If you want traces to be sent to some other place rather than ring
+ * buffer only, just need to register a new trace_export and implement
+ * its own .write() function for writing traces to the storage.
+ *
+ * next		- pointer to the next trace_export
+ * write	- copy traces which have been delt with ->commit() to
+ *		  the destination
+ * flags	- which ftrace to be exported
+ */
+struct trace_export {
+	struct trace_export __rcu	*next;
+	void (*write)(struct trace_export *, const void *, unsigned int);
+	int flags;
+};
+
+struct trace_array;
+
+#ifdef CONFIG_TRACING
+
+int register_ftrace_export(struct trace_export *export);
+int unregister_ftrace_export(struct trace_export *export);
+
+/**
+ * trace_array_puts - write a constant string into the trace buffer.
+ * @tr:    The trace array to write to
+ * @str:   The constant string to write
+ */
+#define trace_array_puts(tr, str)					\
+	({								\
+		str ? __trace_array_puts(tr, _THIS_IP_, str, strlen(str)) : -1;	\
+	})
+int __trace_array_puts(struct trace_array *tr, unsigned long ip,
+		       const char *str, int size);
+
+void trace_printk_init_buffers(void);
+__printf(3, 4)
+int trace_array_printk(struct trace_array *tr, unsigned long ip,
+		       const char *fmt, ...);
+int trace_array_init_printk(struct trace_array *tr);
+void trace_array_put(struct trace_array *tr);
+struct trace_array *trace_array_get_by_name(const char *name);
+int trace_array_destroy(struct trace_array *tr);
+
+/* For osnoise tracer */
+int osnoise_arch_register(void);
+void osnoise_arch_unregister(void);
+void osnoise_trace_irq_entry(int id);
+void osnoise_trace_irq_exit(int id, const char *desc);
+
+#else /* CONFIG_TRACING */
+static inline int register_ftrace_export(struct trace_export *export)
+{
+	return -EINVAL;
+}
+static inline int unregister_ftrace_export(struct trace_export *export)
+{
+	return 0;
+}
+static inline void trace_printk_init_buffers(void)
+{
+}
+static inline int trace_array_printk(struct trace_array *tr, unsigned long ip,
+				     const char *fmt, ...)
+{
+	return 0;
+}
+static inline int trace_array_init_printk(struct trace_array *tr)
+{
+	return -EINVAL;
+}
+static inline void trace_array_put(struct trace_array *tr)
+{
+}
+static inline struct trace_array *trace_array_get_by_name(const char *name)
+{
+	return NULL;
+}
+static inline int trace_array_destroy(struct trace_array *tr)
+{
+	return 0;
+}
+#endif	/* CONFIG_TRACING */
+
+#endif	/* _LINUX_TRACE_H */