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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 7FB6CC433DB for ; Thu, 4 Mar 2021 09:04:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5BB2664F23 for ; Thu, 4 Mar 2021 09:04:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237355AbhCDJD6 (ORCPT ); Thu, 4 Mar 2021 04:03:58 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237297AbhCDJDY (ORCPT ); Thu, 4 Mar 2021 04:03:24 -0500 Received: from mail-ej1-x62a.google.com (mail-ej1-x62a.google.com [IPv6:2a00:1450:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 69335C061763 for ; Thu, 4 Mar 2021 01:02:23 -0800 (PST) Received: by mail-ej1-x62a.google.com with SMTP id dx17so20286042ejb.2 for ; Thu, 04 Mar 2021 01:02:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=0G6CjvHclW//LpDCf+tDPu2/tIHhMhu0kmCrwXfNY8I=; b=jhljYura/F87CYx8r/d4TsLAUCEqaT3Xmj//8RiCcLDZFY76HltcM1w0LXiEPRK3oB Il3ICvs4Ss6PC7Vm4QwTWYegLa8oWx/zsfL5UqoUWVGlvQsuD5/lV5Ui8jRY6bSrqi3S RyMC+aXD6HOzl55d2B3a7ma1jSK90wzNdMF5sYNil+am51c/oNEG/8poK4KSukJTWsr1 hQv7z+YHniUH0luB+qhpEQGGXdp/pMjq0AxADIXAwN+LvYt+W1Wk04B7jeRz1wfw/F6F uOIq+598UjNIfYFxPsERtUIXN4WwbVFVZTW2E8HpJI8mpbnlR2XEAPTkNoPJVn04Ezs/ yz0g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=0G6CjvHclW//LpDCf+tDPu2/tIHhMhu0kmCrwXfNY8I=; b=I9rhH5TxQemgdPmJ8S39i8LCe97VZ18B9KFQCmSpiAQvrSkbQ13CnVEGdHws64PPKd xY/u62d3qVRBnX7kFNVL8iKrHOm3ZkbzoBSQOU1DSHeCCsIQDRZa/OcbEuyI/n5Lrymr KdmvKNi39lL1/2xAWw5xDfB5cZ09cFEsO0vtDDNdakd8O0f1qXx+7WvD9h1lwYToRcrL YY/34IaguzI4bhmKip3pzrvlJS3JQacSaFYF5k14FpWA47/8UkcG4SrT3FEfKr3WUeQ2 +VZVLiJLY9iycWwYSXZ0VvZHxbQrOShFyQqo9BlD6uuA714Lh2XKlncbCsVxVOPQGn1P kDFw== X-Gm-Message-State: AOAM531UPKWANSziy0ZgGOJ8+A5BpUAv7+16R740C7MFJiRKf8tGK27m Q1YdI1W9rCQ/LNHsqxTs9e790bv/3ykmUQ== X-Google-Smtp-Source: ABdhPJx9GwQnvzlOa15RFKtih3Zo1gZo0KsvynU5q7SE9kP3RW2qht6j3bS+NlN8zMv+fUIhf+AN4g== X-Received: by 2002:a17:906:4f96:: with SMTP id o22mr3023159eju.511.1614848541941; Thu, 04 Mar 2021 01:02:21 -0800 (PST) Received: from localhost.localdomain ([95.87.199.88]) by smtp.gmail.com with ESMTPSA id f22sm23123552eje.34.2021.03.04.01.02.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 Mar 2021 01:02:21 -0800 (PST) From: "Yordan Karadzhov (VMware)" To: linux-kernel@vger.kernel.org Cc: tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, "Yordan Karadzhov (VMware)" Subject: [RFC PATCH 4/5] tracing: Unify the logic for function tracing options Date: Thu, 4 Mar 2021 11:01:40 +0200 Message-Id: <20210304090141.207309-5-y.karadz@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210304090141.207309-1-y.karadz@gmail.com> References: <20210304090141.207309-1-y.karadz@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Signed-off-by: Yordan Karadzhov (VMware) --- kernel/trace/trace_functions.c | 66 ++++++++++++++++++++-------------- 1 file changed, 40 insertions(+), 26 deletions(-) diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index f93723ca66bc..6c912eb0508a 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -27,13 +27,17 @@ function_trace_call(unsigned long ip, unsigned long parent_ip, static void function_stack_trace_call(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs); +static ftrace_func_t select_trace_function(u32 flags_val); 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; @@ -97,12 +101,9 @@ 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); @@ -205,6 +206,18 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip, local_irq_restore(flags); } +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 struct tracer_opt func_opts[] = { #ifdef CONFIG_STACKTRACE { TRACER_OPT(func_stack_trace, TRACE_FUNC_OPT_STACK) }, @@ -213,7 +226,7 @@ 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 +248,31 @@ 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; + ftrace_func_t func; + u32 new_flags_val; - /* We can change this flag when not running. */ - if (tr->current_trace != &function_trace) - break; + /* Do nothing if already set. */ + if (!!set == !!(func_flags.val & bit)) + return 0; - unregister_ftrace_function(tr->ops); + /* We can change this flag only when not running. */ + if (tr->current_trace != &function_trace) + 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); - } + new_flags_val = (func_flags.val & ~(1UL << (bit - 1))); + new_flags_val |= (set << (bit - 1)); - break; - default: + func = select_trace_function(new_flags_val); + 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; } -- 2.25.1