tracing/filters: add TRACE_EVENT_FORMAT_NOFILTER event macro

Frederic Weisbecker suggested that the trace_special event shouldn't be
filterable; this patch adds a TRACE_EVENT_FORMAT_NOFILTER event macro
that allows an event format to be exported without having a filter
attached, and removes filtering from the trace_special event.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 33 insertions, 0 deletions

diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index f4e46616c48e..77c494f5e1d6 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -65,6 +65,22 @@ ftrace_format_##call(struct trace_seq *s)				\
         return ret;                                                     \
 }
 
+#undef TRACE_EVENT_FORMAT_NOFILTER
+#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct,    \
+                                    tpfmt)                              \
+static int                                                              \
+ftrace_format_##call(struct trace_seq *s)                               \
+{                                                                       \
+        struct args field;                                              \
+        int ret;                                                        \
+                                                                        \
+        tstruct;                                                        \
+                                                                        \
+        trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt);            \
+                                                                        \
+        return ret;                                                     \
+}
+
 #include "trace_event_types.h"
 
 #undef TRACE_ZERO_CHAR
@@ -109,6 +125,19 @@ static int ftrace_raw_init_event_##call(void)				\
         return 0;                                                       \
 }                                                                       \
 
+#undef TRACE_EVENT_FORMAT_NOFILTER
+#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct,    \
+                                    tpfmt)                              \
+                                                                        \
+struct ftrace_event_call __used                                         \
+__attribute__((__aligned__(4)))                                         \
+__attribute__((section("_ftrace_events"))) event_##call = {             \
+        .name                   = #call,                                \
+        .id                     = proto,                                \
+        .system                 = __stringify(TRACE_SYSTEM),            \
+        .show_format            = ftrace_format_##call,                 \
+};
+
 #include "trace_event_types.h"
 
 #undef TRACE_FIELD
@@ -150,4 +179,8 @@ ftrace_define_fields_##call(void)					\
         return ret;                                                     \
 }
 
+#undef TRACE_EVENT_FORMAT_NOFILTER
+#define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct,    \
+                                    tpfmt)
+
 #include "trace_event_types.h"