From 97419875865859fd2403e66266c02ce028e2f5ab Mon Sep 17 00:00:00 2001 From: Josh Stone Date: Mon, 24 Aug 2009 14:43:13 -0700 Subject: tracing: Move tracepoint callbacks from declaration to definition It's not strictly correct for the tracepoint reg/unreg callbacks to occur when a client is hooking up, because the actual tracepoint may not be present yet. This happens to be fine for syscall, since that's in the core kernel, but it would cause problems for tracepoints defined in a module that hasn't been loaded yet. It also means the reg/unreg has to be EXPORTed for any modules to use the tracepoint (as in SystemTap). This patch removes DECLARE_TRACE_WITH_CALLBACK, and instead introduces DEFINE_TRACE_FN which stores the callbacks in struct tracepoint. The callbacks are used now when the active state of the tracepoint changes in set_tracepoint & disable_tracepoint. This also introduces TRACE_EVENT_FN, so ftrace events can also provide registration callbacks if needed. Signed-off-by: Josh Stone Cc: Jason Baron Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Li Zefan Cc: Steven Rostedt Cc: Peter Zijlstra Cc: Mathieu Desnoyers Cc: Jiaying Zhang Cc: Martin Bligh Cc: Lai Jiangshan Cc: Paul Mundt Cc: Martin Schwidefsky Cc: Heiko Carstens LKML-Reference: <1251150194-1713-4-git-send-email-jistone@redhat.com> Signed-off-by: Frederic Weisbecker --- include/trace/ftrace.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/trace/ftrace.h') diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 127400255e4..3a0b44bdabf 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -42,6 +42,15 @@ }; \ static struct ftrace_event_call event_##name +/* Callbacks are meaningless to ftrace. */ +#undef TRACE_EVENT_FN +#define TRACE_EVENT_FN(name, proto, args, tstruct, \ + assign, print, reg, unreg) \ + TRACE_EVENT(name, TP_PROTO(proto), TP_ARGS(args), \ + TP_STRUCT__entry(tstruct), \ + TP_fast_assign(assign), \ + TP_printk(print)) + #include TRACE_INCLUDE(TRACE_INCLUDE_FILE) -- cgit v1.2.3-70-g09d2