From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53119C433ED for ; Fri, 16 Apr 2021 17:27:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E2CE613BB for ; Fri, 16 Apr 2021 17:27:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242202AbhDPR1h (ORCPT ); Fri, 16 Apr 2021 13:27:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:56302 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241793AbhDPR1X (ORCPT ); Fri, 16 Apr 2021 13:27:23 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 136BE611C2; Fri, 16 Apr 2021 17:26:58 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94) (envelope-from ) id 1lXSF7-0069lR-4M; Fri, 16 Apr 2021 13:26:57 -0400 Message-ID: <20210416172657.005754827@goodmis.org> User-Agent: quilt/0.66 Date: Fri, 16 Apr 2021 13:26:17 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , "Yordan Karadzhov (VMware)" Subject: [for-next][PATCH 5/7] tracing: Unify the logic for function tracing options References: <20210416172612.086725495@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Yordan Karadzhov (VMware)" Currently the logic for dealing with the options for function tracing has two different implementations. One is used when we set the flags (in "static int func_set_flag()") and another used when we initialize the tracer (in "static int function_trace_init()"). Those two implementations are meant to do essentially the same thing and they are both not very convenient for adding new options. In this patch we add a helper function that provides a single implementation of the logic for dealing with the options and we make it such that new options can be easily added. Link: https://lkml.kernel.org/r/20210415181854.147448-6-y.karadz@gmail.com Signed-off-by: Yordan Karadzhov (VMware) Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_functions.c | 65 ++++++++++++++++++++-------------- 1 file changed, 38 insertions(+), 27 deletions(-) diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index f93723ca66bc..f37f73a9b1b8 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -31,9 +31,12 @@ static struct tracer_flags func_flags; /* Our option */ enum { + TRACE_FUNC_NO_OPTS = 0x0, /* No flags set. */ TRACE_FUNC_OPT_STACK = 0x1, }; +#define TRACE_FUNC_OPT_MASK (TRACE_FUNC_OPT_STACK) + int ftrace_allocate_ftrace_ops(struct trace_array *tr) { struct ftrace_ops *ops; @@ -86,6 +89,18 @@ void ftrace_destroy_function_files(struct trace_array *tr) ftrace_free_ftrace_ops(tr); } +static ftrace_func_t select_trace_function(u32 flags_val) +{ + switch (flags_val & TRACE_FUNC_OPT_MASK) { + case TRACE_FUNC_NO_OPTS: + return function_trace_call; + case TRACE_FUNC_OPT_STACK: + return function_stack_trace_call; + default: + return NULL; + } +} + static int function_trace_init(struct trace_array *tr) { ftrace_func_t func; @@ -97,12 +112,9 @@ static int function_trace_init(struct trace_array *tr) if (!tr->ops) return -ENOMEM; - /* Currently only the global instance can do stack tracing */ - if (tr->flags & TRACE_ARRAY_FL_GLOBAL && - func_flags.val & TRACE_FUNC_OPT_STACK) - func = function_stack_trace_call; - else - func = function_trace_call; + func = select_trace_function(func_flags.val); + if (!func) + return -EINVAL; ftrace_init_array_ops(tr, func); @@ -213,7 +225,7 @@ static struct tracer_opt func_opts[] = { }; static struct tracer_flags func_flags = { - .val = 0, /* By default: all flags disabled */ + .val = TRACE_FUNC_NO_OPTS, /* By default: all flags disabled */ .opts = func_opts }; @@ -235,30 +247,29 @@ static struct tracer function_trace; static int func_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) { - switch (bit) { - case TRACE_FUNC_OPT_STACK: - /* do nothing if already set */ - if (!!set == !!(func_flags.val & TRACE_FUNC_OPT_STACK)) - break; - - /* We can change this flag when not running. */ - if (tr->current_trace != &function_trace) - break; + ftrace_func_t func; + u32 new_flags; - unregister_ftrace_function(tr->ops); + /* Do nothing if already set. */ + if (!!set == !!(func_flags.val & bit)) + return 0; - if (set) { - tr->ops->func = function_stack_trace_call; - register_ftrace_function(tr->ops); - } else { - tr->ops->func = function_trace_call; - register_ftrace_function(tr->ops); - } + /* We can change this flag only when not running. */ + if (tr->current_trace != &function_trace) + return 0; - break; - default: + new_flags = (func_flags.val & ~bit) | (set ? bit : 0); + func = select_trace_function(new_flags); + if (!func) return -EINVAL; - } + + /* Check if there's anything to change. */ + if (tr->ops->func == func) + return 0; + + unregister_ftrace_function(tr->ops); + tr->ops->func = func; + register_ftrace_function(tr->ops); return 0; } -- 2.30.1