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-rw-r--r--drivers/staging/sep/sep_trace_events.h188
1 files changed, 188 insertions, 0 deletions
diff --git a/drivers/staging/sep/sep_trace_events.h b/drivers/staging/sep/sep_trace_events.h
new file mode 100644
index 000000000000..2b053a93afe6
--- /dev/null
+++ b/drivers/staging/sep/sep_trace_events.h
@@ -0,0 +1,188 @@
+/*
+ * If TRACE_SYSTEM is defined, that will be the directory created
+ * in the ftrace directory under /sys/kernel/debug/tracing/events/<system>
+ *
+ * The define_trace.h below will also look for a file name of
+ * TRACE_SYSTEM.h where TRACE_SYSTEM is what is defined here.
+ * In this case, it would look for sample.h
+ *
+ * If the header name will be different than the system name
+ * (as in this case), then you can override the header name that
+ * define_trace.h will look up by defining TRACE_INCLUDE_FILE
+ *
+ * This file is called trace-events-sample.h but we want the system
+ * to be called "sample". Therefore we must define the name of this
+ * file:
+ *
+ * #define TRACE_INCLUDE_FILE trace-events-sample
+ *
+ * As we do an the bottom of this file.
+ *
+ * Notice that TRACE_SYSTEM should be defined outside of #if
+ * protection, just like TRACE_INCLUDE_FILE.
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM sep
+
+/*
+ * Notice that this file is not protected like a normal header.
+ * We also must allow for rereading of this file. The
+ *
+ * || defined(TRACE_HEADER_MULTI_READ)
+ *
+ * serves this purpose.
+ */
+#if !defined(_TRACE_SEP_EVENTS_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_SEP_EVENTS_H
+
+#ifdef SEP_PERF_DEBUG
+#define SEP_TRACE_FUNC_IN() trace_sep_func_start(__func__, 0)
+#define SEP_TRACE_FUNC_OUT(branch) trace_sep_func_end(__func__, branch)
+#define SEP_TRACE_EVENT(branch) trace_sep_misc_event(__func__, branch)
+#else
+#define SEP_TRACE_FUNC_IN()
+#define SEP_TRACE_FUNC_OUT(branch)
+#define SEP_TRACE_EVENT(branch)
+#endif
+
+
+/*
+ * All trace headers should include tracepoint.h, until we finally
+ * make it into a standard header.
+ */
+#include <linux/tracepoint.h>
+
+/*
+ * The TRACE_EVENT macro is broken up into 5 parts.
+ *
+ * name: name of the trace point. This is also how to enable the tracepoint.
+ * A function called trace_foo_bar() will be created.
+ *
+ * proto: the prototype of the function trace_foo_bar()
+ * Here it is trace_foo_bar(char *foo, int bar).
+ *
+ * args: must match the arguments in the prototype.
+ * Here it is simply "foo, bar".
+ *
+ * struct: This defines the way the data will be stored in the ring buffer.
+ * There are currently two types of elements. __field and __array.
+ * a __field is broken up into (type, name). Where type can be any
+ * type but an array.
+ * For an array. there are three fields. (type, name, size). The
+ * type of elements in the array, the name of the field and the size
+ * of the array.
+ *
+ * __array( char, foo, 10) is the same as saying char foo[10].
+ *
+ * fast_assign: This is a C like function that is used to store the items
+ * into the ring buffer.
+ *
+ * printk: This is a way to print out the data in pretty print. This is
+ * useful if the system crashes and you are logging via a serial line,
+ * the data can be printed to the console using this "printk" method.
+ *
+ * Note, that for both the assign and the printk, __entry is the handler
+ * to the data structure in the ring buffer, and is defined by the
+ * TP_STRUCT__entry.
+ */
+TRACE_EVENT(sep_func_start,
+
+ TP_PROTO(const char *name, int branch),
+
+ TP_ARGS(name, branch),
+
+ TP_STRUCT__entry(
+ __array(char, name, 20)
+ __field(int, branch)
+ ),
+
+ TP_fast_assign(
+ strncpy(__entry->name, name, 20);
+ __entry->branch = branch;
+ ),
+
+ TP_printk("func_start %s %d", __entry->name, __entry->branch)
+);
+
+TRACE_EVENT(sep_func_end,
+
+ TP_PROTO(const char *name, int branch),
+
+ TP_ARGS(name, branch),
+
+ TP_STRUCT__entry(
+ __array(char, name, 20)
+ __field(int, branch)
+ ),
+
+ TP_fast_assign(
+ strncpy(__entry->name, name, 20);
+ __entry->branch = branch;
+ ),
+
+ TP_printk("func_end %s %d", __entry->name, __entry->branch)
+);
+
+TRACE_EVENT(sep_misc_event,
+
+ TP_PROTO(const char *name, int branch),
+
+ TP_ARGS(name, branch),
+
+ TP_STRUCT__entry(
+ __array(char, name, 20)
+ __field(int, branch)
+ ),
+
+ TP_fast_assign(
+ strncpy(__entry->name, name, 20);
+ __entry->branch = branch;
+ ),
+
+ TP_printk("misc_event %s %d", __entry->name, __entry->branch)
+);
+
+
+#endif
+
+/***** NOTICE! The #if protection ends here. *****/
+
+
+/*
+ * There are several ways I could have done this. If I left out the
+ * TRACE_INCLUDE_PATH, then it would default to the kernel source
+ * include/trace/events directory.
+ *
+ * I could specify a path from the define_trace.h file back to this
+ * file.
+ *
+ * #define TRACE_INCLUDE_PATH ../../samples/trace_events
+ *
+ * But the safest and easiest way to simply make it use the directory
+ * that the file is in is to add in the Makefile:
+ *
+ * CFLAGS_trace-events-sample.o := -I$(src)
+ *
+ * This will make sure the current path is part of the include
+ * structure for our file so that define_trace.h can find it.
+ *
+ * I could have made only the top level directory the include:
+ *
+ * CFLAGS_trace-events-sample.o := -I$(PWD)
+ *
+ * And then let the path to this directory be the TRACE_INCLUDE_PATH:
+ *
+ * #define TRACE_INCLUDE_PATH samples/trace_events
+ *
+ * But then if something defines "samples" or "trace_events" as a macro
+ * then we could risk that being converted too, and give us an unexpected
+ * result.
+ */
+#undef TRACE_INCLUDE_PATH
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_PATH .
+/*
+ * TRACE_INCLUDE_FILE is not needed if the filename and TRACE_SYSTEM are equal
+ */
+#define TRACE_INCLUDE_FILE sep_trace_events
+#include <trace/define_trace.h>