From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753973Ab0IXJAl (ORCPT ); Fri, 24 Sep 2010 05:00:41 -0400 Received: from hera.kernel.org ([140.211.167.34]:33795 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753531Ab0IXJAj (ORCPT ); Fri, 24 Sep 2010 05:00:39 -0400 Date: Fri, 24 Sep 2010 09:00:24 GMT From: tip-bot for Jason Baron Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, rostedt@goodmis.org, jbaron@redhat.com, tglx@linutronix.de Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, rostedt@goodmis.org, tglx@linutronix.de, jbaron@redhat.com In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] jump label: Tracepoint support for jump labels Message-ID: Git-Commit-ID: 8f7b50c514206211cc282a4247f7b12f18dee674 X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Fri, 24 Sep 2010 09:00:25 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 8f7b50c514206211cc282a4247f7b12f18dee674 Gitweb: http://git.kernel.org/tip/8f7b50c514206211cc282a4247f7b12f18dee674 Author: Jason Baron AuthorDate: Fri, 17 Sep 2010 11:09:13 -0400 Committer: Steven Rostedt CommitDate: Wed, 22 Sep 2010 16:31:01 -0400 jump label: Tracepoint support for jump labels Make use of the jump label infrastructure for tracepoints. Signed-off-by: Jason Baron LKML-Reference: Signed-off-by: Steven Rostedt --- include/linux/tracepoint.h | 5 ++++- kernel/tracepoint.c | 14 ++++++++++++-- 2 files changed, 16 insertions(+), 3 deletions(-) diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 103d1b6..a4a90b6 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -17,6 +17,7 @@ #include #include #include +#include struct module; struct tracepoint; @@ -145,7 +146,9 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin, extern struct tracepoint __tracepoint_##name; \ static inline void trace_##name(proto) \ { \ - if (unlikely(__tracepoint_##name.state)) \ + JUMP_LABEL(&__tracepoint_##name.state, do_trace); \ + return; \ +do_trace: \ __DO_TRACE(&__tracepoint_##name, \ TP_PROTO(data_proto), \ TP_ARGS(data_args)); \ diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c index c77f3ec..d6073a5 100644 --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -25,6 +25,7 @@ #include #include #include +#include extern struct tracepoint __start___tracepoints[]; extern struct tracepoint __stop___tracepoints[]; @@ -263,7 +264,13 @@ static void set_tracepoint(struct tracepoint_entry **entry, * is used. */ rcu_assign_pointer(elem->funcs, (*entry)->funcs); - elem->state = active; + if (!elem->state && active) { + enable_jump_label(&elem->state); + elem->state = active; + } else if (elem->state && !active) { + disable_jump_label(&elem->state); + elem->state = active; + } } /* @@ -277,7 +284,10 @@ static void disable_tracepoint(struct tracepoint *elem) if (elem->unregfunc && elem->state) elem->unregfunc(); - elem->state = 0; + if (elem->state) { + disable_jump_label(&elem->state); + elem->state = 0; + } rcu_assign_pointer(elem->funcs, NULL); }