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-rw-r--r--Documentation/markers.txt14
-rw-r--r--include/linux/marker.h39
2 files changed, 37 insertions, 16 deletions
diff --git a/Documentation/markers.txt b/Documentation/markers.txt
index 089f6138fcd9..6d275e4ef385 100644
--- a/Documentation/markers.txt
+++ b/Documentation/markers.txt
@@ -70,6 +70,20 @@ a printk warning which identifies the inconsistency:
"Format mismatch for probe probe_name (format), marker (format)"
+Another way to use markers is to simply define the marker without generating any
+function call to actually call into the marker. This is useful in combination
+with tracepoint probes in a scheme like this :
+
+void probe_tracepoint_name(unsigned int arg1, struct task_struct *tsk);
+
+DEFINE_MARKER_TP(marker_eventname, tracepoint_name, probe_tracepoint_name,
+ "arg1 %u pid %d");
+
+notrace void probe_tracepoint_name(unsigned int arg1, struct task_struct *tsk)
+{
+ struct marker *marker = &GET_MARKER(kernel_irq_entry);
+ /* write data to trace buffers ... */
+}
* Probe / marker example
diff --git a/include/linux/marker.h b/include/linux/marker.h
index 57a307018ceb..34c14bc957f5 100644
--- a/include/linux/marker.h
+++ b/include/linux/marker.h
@@ -55,6 +55,22 @@ struct marker {
#ifdef CONFIG_MARKERS
+#define _DEFINE_MARKER(name, tp_name_str, tp_cb, format) \
+ static const char __mstrtab_##name[] \
+ __attribute__((section("__markers_strings"))) \
+ = #name "\0" format; \
+ static struct marker __mark_##name \
+ __attribute__((section("__markers"), aligned(8))) = \
+ { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)], \
+ 0, 0, marker_probe_cb, { __mark_empty_function, NULL},\
+ NULL, tp_name_str, tp_cb }
+
+#define DEFINE_MARKER(name, format) \
+ _DEFINE_MARKER(name, NULL, NULL, format)
+
+#define DEFINE_MARKER_TP(name, tp_name, tp_cb, format) \
+ _DEFINE_MARKER(name, #tp_name, tp_cb, format)
+
/*
* Note : the empty asm volatile with read constraint is used here instead of a
* "used" attribute to fix a gcc 4.1.x bug.
@@ -68,14 +84,7 @@ struct marker {
*/
#define __trace_mark(generic, name, call_private, format, args...) \
do { \
- static const char __mstrtab_##name[] \
- __attribute__((section("__markers_strings"))) \
- = #name "\0" format; \
- static struct marker __mark_##name \
- __attribute__((section("__markers"), aligned(8))) = \
- { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)], \
- 0, 0, marker_probe_cb, \
- { __mark_empty_function, NULL}, NULL, NULL, NULL }; \
+ DEFINE_MARKER(name, format); \
__mark_check_format(format, ## args); \
if (unlikely(__mark_##name.state)) { \
(*__mark_##name.call) \
@@ -89,14 +98,7 @@ struct marker {
{ \
register_trace_##tp_name(tp_cb); \
} \
- static const char __mstrtab_##name[] \
- __attribute__((section("__markers_strings"))) \
- = #name "\0" format; \
- static struct marker __mark_##name \
- __attribute__((section("__markers"), aligned(8))) = \
- { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)], \
- 0, 0, marker_probe_cb, \
- { __mark_empty_function, NULL}, NULL, #tp_name, tp_cb };\
+ DEFINE_MARKER_TP(name, tp_name, tp_cb, format); \
__mark_check_format(format, ## args); \
(*__mark_##name.call)(&__mark_##name, call_private, \
## args); \
@@ -104,7 +106,11 @@ struct marker {
extern void marker_update_probe_range(struct marker *begin,
struct marker *end);
+
+#define GET_MARKER(name) (__mark_##name)
+
#else /* !CONFIG_MARKERS */
+#define DEFINE_MARKER(name, tp_name, tp_cb, format)
#define __trace_mark(generic, name, call_private, format, args...) \
__mark_check_format(format, ## args)
#define __trace_mark_tp(name, call_private, tp_name, tp_cb, format, args...) \
@@ -118,6 +124,7 @@ extern void marker_update_probe_range(struct marker *begin,
static inline void marker_update_probe_range(struct marker *begin,
struct marker *end)
{ }
+#define GET_MARKER(name)
#endif /* CONFIG_MARKERS */
/**