tracepoints: add DECLARE_TRACE() and DEFINE_TRACE()

Impact: API *CHANGE*. Must update all tracepoint users.

Add DEFINE_TRACE() to tracepoints to let them declare the tracepoint
structure in a single spot for all the kernel. It helps reducing memory
consumption, especially when declaring a lot of tracepoints, e.g. for
kmalloc tracing.

*API CHANGE WARNING*: now, DECLARE_TRACE() must be used in headers for
tracepoint declarations rather than DEFINE_TRACE(). This is the sane way
to do it. The name previously used was misleading.

Updates scheduler instrumentation to follow this API change.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 0 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index ae2b92be5fae..f995d2418668 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -54,6 +54,10 @@
 #include <asm/pgtable.h>
 #include <asm/mmu_context.h>
 
+DEFINE_TRACE(sched_process_free);
+DEFINE_TRACE(sched_process_exit);
+DEFINE_TRACE(sched_process_wait);
+
 static void exit_mm(struct task_struct * tsk);
 
 static inline int task_detached(struct task_struct *p)