From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753498Ab1KQUu5 (ORCPT ); Thu, 17 Nov 2011 15:50:57 -0500 Received: from mail.openrapids.net ([64.15.138.104]:52394 "EHLO blackscsi.openrapids.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751907Ab1KQUu4 (ORCPT ); Thu, 17 Nov 2011 15:50:56 -0500 Date: Thu, 17 Nov 2011 15:50:53 -0500 From: Mathieu Desnoyers To: Eric Dumazet Cc: Peter Zijlstra , linux-kernel , Ingo Molnar , Christoph Lameter , rostedt Subject: [RFC PATCH] Tracepoint: introduce tracepoint() API Message-ID: <20111117205053.GA26484@Krystal> References: <1321502104.3274.22.camel@edumazet-laptop> <1321543520.27735.67.camel@twins> <20111117155617.GA12665@Krystal> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <20111117155617.GA12665@Krystal> X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.27.31-grsec (i686) X-Uptime: 15:41:08 up 589 days, 6:30, 4 users, load average: 0.40, 0.18, 0.11 User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Introduce: tracepoint(event_name, arg1, arg2, ...) while keeping the old tracepoint API in place, e.g.: trace_event_name(arg1, arg2, ...) This allows skipping parameter side-effects (pointer dereference, function calls, ...) when the tracepoint is not dynamically activated. Signed-off-by: Mathieu Desnoyers --- diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index d530a44..c9c73f7 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -107,6 +107,12 @@ void tracepoint_update_probe_range(struct tracepoint * const *begin, #ifdef CONFIG_TRACEPOINTS +#define tracepoint(name, args...) \ + do { \ + if (static_branch(&__tracepoint_##name.key)) \ + __trace_##name(args); \ + } while (0) + /* * it_func[0] is never NULL because there is at least one element in the array * when the array itself is non NULL. @@ -144,13 +150,17 @@ void tracepoint_update_probe_range(struct tracepoint * const *begin, */ #define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \ extern struct tracepoint __tracepoint_##name; \ + static inline void __trace_##name(proto) \ + { \ + __DO_TRACE(&__tracepoint_##name, \ + TP_PROTO(data_proto), \ + TP_ARGS(data_args), \ + TP_CONDITION(cond)); \ + } \ static inline void trace_##name(proto) \ { \ if (static_branch(&__tracepoint_##name.key)) \ - __DO_TRACE(&__tracepoint_##name, \ - TP_PROTO(data_proto), \ - TP_ARGS(data_args), \ - TP_CONDITION(cond)); \ + __trace_##name(args); \ } \ static inline int \ register_trace_##name(void (*probe)(data_proto), void *data) \ @@ -193,7 +203,12 @@ void tracepoint_update_probe_range(struct tracepoint * const *begin, EXPORT_SYMBOL(__tracepoint_##name) #else /* !CONFIG_TRACEPOINTS */ + +#define tracepoint(name, args...) __trace_##name(args) + #define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \ + static inline void __trace_##name(proto) \ + { } \ static inline void trace_##name(proto) \ { } \ static inline int \ -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com