From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755699Ab0A2J0N (ORCPT ); Fri, 29 Jan 2010 04:26:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754989Ab0A2J0H (ORCPT ); Fri, 29 Jan 2010 04:26:07 -0500 Received: from hera.kernel.org ([140.211.167.34]:50613 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932192Ab0A2J0E (ORCPT ); Fri, 29 Jan 2010 04:26:04 -0500 Date: Fri, 29 Jan 2010 09:25:12 GMT From: tip-bot for Lai Jiangshan Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, fweisbec@gmail.com, rostedt@goodmis.org, tglx@linutronix.de, laijs@cn.fujitsu.com, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, fweisbec@gmail.com, rostedt@goodmis.org, tglx@linutronix.de, laijs@cn.fujitsu.com, mingo@elte.hu In-Reply-To: <4B4DB0B6.7040607@cn.fujitsu.com> References: <4B4DB0B6.7040607@cn.fujitsu.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:tracing/core] tracing: Simplify test for function_graph tracing start point Message-ID: Git-Commit-ID: ea2c68a08fedb5053ba312d661e47df9f4d72411 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, 29 Jan 2010 09:25:12 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: ea2c68a08fedb5053ba312d661e47df9f4d72411 Gitweb: http://git.kernel.org/tip/ea2c68a08fedb5053ba312d661e47df9f4d72411 Author: Lai Jiangshan AuthorDate: Wed, 13 Jan 2010 19:38:30 +0800 Committer: Frederic Weisbecker CommitDate: Fri, 29 Jan 2010 01:05:12 +0100 tracing: Simplify test for function_graph tracing start point In the function graph tracer, a calling function is to be traced only when it is enabled through the set_graph_function file, or when it is nested in an enabled function. Current code uses TSK_TRACE_FL_GRAPH to test whether it is nested or not. Looking at the code, we can get this: (trace->depth > 0) <==> (TSK_TRACE_FL_GRAPH is set) trace->depth is more explicit to tell that it is nested. So we use trace->depth directly and simplify the code. No functionality is changed. TSK_TRACE_FL_GRAPH is not removed yet, it is left for future usage. Signed-off-by: Lai Jiangshan Cc: Ingo Molnar Cc: Steven Rostedt LKML-Reference: <4B4DB0B6.7040607@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker --- kernel/trace/trace.h | 2 +- kernel/trace/trace_functions_graph.c | 8 ++------ 2 files changed, 3 insertions(+), 7 deletions(-) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 4df6a77..ce077fb 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -504,7 +504,7 @@ static inline int ftrace_graph_addr(unsigned long addr) { int i; - if (!ftrace_graph_count || test_tsk_trace_graph(current)) + if (!ftrace_graph_count) return 1; for (i = 0; i < ftrace_graph_count; i++) { diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index f225229..616b135 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -215,7 +215,8 @@ int trace_graph_entry(struct ftrace_graph_ent *trace) if (!ftrace_trace_task(current)) return 0; - if (!ftrace_graph_addr(trace->func)) + /* trace it when it is-nested-in or is a function enabled. */ + if (!(trace->depth || ftrace_graph_addr(trace->func))) return 0; local_irq_save(flags); @@ -228,9 +229,6 @@ int trace_graph_entry(struct ftrace_graph_ent *trace) } else { ret = 0; } - /* Only do the atomic if it is not already set */ - if (!test_tsk_trace_graph(current)) - set_tsk_trace_graph(current); atomic_dec(&data->disabled); local_irq_restore(flags); @@ -278,8 +276,6 @@ void trace_graph_return(struct ftrace_graph_ret *trace) pc = preempt_count(); __trace_graph_return(tr, trace, flags, pc); } - if (!trace->depth) - clear_tsk_trace_graph(current); atomic_dec(&data->disabled); local_irq_restore(flags); }