From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756627Ab1EFPsw (ORCPT ); Fri, 6 May 2011 11:48:52 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:38589 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756527Ab1EFPro (ORCPT ); Fri, 6 May 2011 11:47:44 -0400 X-Authority-Analysis: v=1.1 cv=aqMe+0lCtaYvy4h0jyaoPGyq+DPF+P6rPG2xbekoY9Q= c=1 sm=0 a=vhdKIqpQuCYA:10 a=CYgfuJdlo0QA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=OPBmh+XkhLl+Enan7BmTLg==:17 a=20KFwNOVAAAA:8 a=meVymXHHAAAA:8 a=ub5fkPtXNE4uSVaks_IA:9 a=OZ5PjjlgJ_G-0UEiIh0A:7 a=jEp0ucaQiEUA:10 a=jeBq3FmKZ4MA:10 a=OPBmh+XkhLl+Enan7BmTLg==:117 X-Cloudmark-Score: 0 X-Originating-IP: 67.242.120.143 Message-Id: <20110506154741.169980717@goodmis.org> User-Agent: quilt/0.48-1 Date: Fri, 06 May 2011 11:26:32 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Thomas Gleixner , Frederic Weisbecker , Mathieu Desnoyers , Lai Jiangshan , Li Zefan , Jiri Olsa , David Sharp , Vaibhav Nagarnaik , Michael Rubin Subject: [RFC][PATCH 08/13] ftrace: Have global_ops store the functions that are to be traced References: <20110506152624.776982312@goodmis.org> Content-Disposition: inline; filename=0008-ftrace-Have-global_ops-store-the-functions-that-are-.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt This is a step towards each ops structure defining its own set of functions to trace. As the current code with pid's and such are specific to the global_ops, it is restructured to be used with the global ops. Signed-off-by: Steven Rostedt --- kernel/trace/ftrace.c | 69 +++++++++++++++++++++++++++++++++++++----------- 1 files changed, 53 insertions(+), 16 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 8fef1d9..dcce0bf 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -91,6 +91,7 @@ static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; +static struct ftrace_ops global_ops; /* * Traverse the ftrace_list, invoking all entries. The reason that we @@ -153,7 +154,7 @@ static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) } #endif -static void update_ftrace_function(void) +static void update_global_ops(void) { ftrace_func_t func; @@ -173,6 +174,18 @@ static void update_ftrace_function(void) set_ftrace_pid_function(func); func = ftrace_pid_func; } + + global_ops.func = func; +} + +static void update_ftrace_function(void) +{ + ftrace_func_t func; + + update_global_ops(); + + func = global_ops.func; + #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST ftrace_trace_function = func; #else @@ -181,24 +194,19 @@ static void update_ftrace_function(void) #endif } -static int __register_ftrace_function(struct ftrace_ops *ops) +static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) { - ops->next = ftrace_list; + ops->next = *list; /* * We are entering ops into the ftrace_list but another * CPU might be walking that list. We need to make sure * the ops->next pointer is valid before another CPU sees * the ops pointer included into the ftrace_list. */ - rcu_assign_pointer(ftrace_list, ops); - - if (ftrace_enabled) - update_ftrace_function(); - - return 0; + rcu_assign_pointer(*list, ops); } -static int __unregister_ftrace_function(struct ftrace_ops *ops) +static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) { struct ftrace_ops **p; @@ -206,13 +214,12 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) * If we are removing the last function, then simply point * to the ftrace_stub. */ - if (ftrace_list == ops && ops->next == &ftrace_list_end) { - ftrace_trace_function = ftrace_stub; - ftrace_list = &ftrace_list_end; + if (*list == ops && ops->next == &ftrace_list_end) { + *list = &ftrace_list_end; return 0; } - for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) + for (p = list; *p != &ftrace_list_end; p = &(*p)->next) if (*p == ops) break; @@ -220,7 +227,37 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) return -1; *p = (*p)->next; + return 0; +} + +static int __register_ftrace_function(struct ftrace_ops *ops) +{ + if (ftrace_disabled) + return -ENODEV; + + if (FTRACE_WARN_ON(ops == &global_ops)) + return -EINVAL; + + add_ftrace_ops(&ftrace_list, ops); + if (ftrace_enabled) + update_ftrace_function(); + + return 0; +} +static int __unregister_ftrace_function(struct ftrace_ops *ops) +{ + int ret; + + if (ftrace_disabled) + return -ENODEV; + + if (FTRACE_WARN_ON(ops == &global_ops)) + return -EINVAL; + + ret = remove_ftrace_ops(&ftrace_list, ops); + if (ret < 0) + return ret; if (ftrace_enabled) update_ftrace_function(); @@ -894,7 +931,7 @@ enum { FTRACE_OPS_FL_ENABLED = 1, }; -struct ftrace_ops global_ops = { +static struct ftrace_ops global_ops = { .func = ftrace_stub, .notrace_hash = EMPTY_HASH, .filter_hash = EMPTY_HASH, @@ -3263,7 +3300,7 @@ void __init ftrace_init(void) #else -struct ftrace_ops global_ops = { +static struct ftrace_ops global_ops = { .func = ftrace_stub, }; -- 1.7.2.3