From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756401Ab3AYP1W (ORCPT ); Fri, 25 Jan 2013 10:27:22 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:25183 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755481Ab3AYP1T (ORCPT ); Fri, 25 Jan 2013 10:27:19 -0500 X-Authority-Analysis: v=2.0 cv=bJmU0YCZ c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=d9aeljUNHtYA:10 a=5SG0PmZfjMsA:10 a=Q9fys5e9bTEA:10 a=meVymXHHAAAA:8 a=hZ6iKA16joIA:10 a=20KFwNOVAAAA:8 a=drOt6m5kAAAA:8 a=zEuoMAFUTG65KY6yyiYA:9 a=PUjeQqilurYA:10 a=jEp0ucaQiEUA:10 a=jeBq3FmKZ4MA:10 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Authenticated-User: X-Originating-IP: 74.67.115.198 Message-ID: <1359127637.21576.219.camel@gandalf.local.home> Subject: Re: [tracepoint] cargo-culting considered harmful... From: Steven Rostedt To: Mathieu Desnoyers Cc: Al Viro , linux-kernel@vger.kernel.org, Linus Torvalds , Andrew Morton Date: Fri, 25 Jan 2013 10:27:17 -0500 In-Reply-To: <20130125143850.GA20597@Krystal> References: <20130123225523.GY4939@ZenIV.linux.org.uk> <20130123230235.GC5434@home.goodmis.org> <20130125143850.GA20597@Krystal> Content-Type: text/plain; charset="ISO-8859-15" X-Mailer: Evolution 3.4.4-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2013-01-25 at 09:38 -0500, Mathieu Desnoyers wrote: > Yep, I'd be OK with removing this example, since now all users are > expected to user TRACE_EVENT(), which is built on top of tracepoints. Can I get your Acked-by for the following patch? -- Steve commit 867a31fab0a064e54147371425f9fdef933e3d1d Author: Steven Rostedt Date: Fri Jan 25 09:46:36 2013 -0500 tracing: Remove tracepoint sample code The tracepoint sample code was used to teach developers how to create their own tracepoints. But now the trace_events have been added as a higher level that is used directly by developers today. Only the trace_event code should use the tracepoint interface directly and no new tracepoints should be added. Besides, the example had a race condition with the use of the ->d_name.name dentry field, as pointed out by Al Viro. Best just to remove the code so it wont be used by other developers. Cc: Al Viro Cc: Mathieu Desnoyers Signed-off-by: Steven Rostedt diff --git a/samples/Kconfig b/samples/Kconfig index 7b6792a..6181c2c 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -5,12 +5,6 @@ menuconfig SAMPLES if SAMPLES -config SAMPLE_TRACEPOINTS - tristate "Build tracepoints examples -- loadable modules only" - depends on TRACEPOINTS && m - help - This build tracepoints example modules. - config SAMPLE_TRACE_EVENTS tristate "Build trace_events examples -- loadable modules only" depends on EVENT_TRACING && m diff --git a/samples/Makefile b/samples/Makefile index 5ef08bb..1a60c62 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -1,4 +1,4 @@ # Makefile for Linux samples code -obj-$(CONFIG_SAMPLES) += kobject/ kprobes/ tracepoints/ trace_events/ \ +obj-$(CONFIG_SAMPLES) += kobject/ kprobes/ trace_events/ \ hw_breakpoint/ kfifo/ kdb/ hidraw/ rpmsg/ seccomp/ diff --git a/samples/tracepoints/Makefile b/samples/tracepoints/Makefile deleted file mode 100644 index 36479ad..0000000 --- a/samples/tracepoints/Makefile +++ /dev/null @@ -1,6 +0,0 @@ -# builds the tracepoint example kernel modules; -# then to use one (as root): insmod - -obj-$(CONFIG_SAMPLE_TRACEPOINTS) += tracepoint-sample.o -obj-$(CONFIG_SAMPLE_TRACEPOINTS) += tracepoint-probe-sample.o -obj-$(CONFIG_SAMPLE_TRACEPOINTS) += tracepoint-probe-sample2.o diff --git a/samples/tracepoints/tp-samples-trace.h b/samples/tracepoints/tp-samples-trace.h deleted file mode 100644 index 4d46be9..0000000 --- a/samples/tracepoints/tp-samples-trace.h +++ /dev/null @@ -1,11 +0,0 @@ -#ifndef _TP_SAMPLES_TRACE_H -#define _TP_SAMPLES_TRACE_H - -#include /* for struct inode and struct file */ -#include - -DECLARE_TRACE(subsys_event, - TP_PROTO(struct inode *inode, struct file *file), - TP_ARGS(inode, file)); -DECLARE_TRACE_NOARGS(subsys_eventb); -#endif diff --git a/samples/tracepoints/tracepoint-probe-sample.c b/samples/tracepoints/tracepoint-probe-sample.c deleted file mode 100644 index 744c0b9..0000000 --- a/samples/tracepoints/tracepoint-probe-sample.c +++ /dev/null @@ -1,57 +0,0 @@ -/* - * tracepoint-probe-sample.c - * - * sample tracepoint probes. - */ - -#include -#include -#include -#include "tp-samples-trace.h" - -/* - * Here the caller only guarantees locking for struct file and struct inode. - * Locking must therefore be done in the probe to use the dentry. - */ -static void probe_subsys_event(void *ignore, - struct inode *inode, struct file *file) -{ - path_get(&file->f_path); - dget(file->f_path.dentry); - printk(KERN_INFO "Event is encountered with filename %s\n", - file->f_path.dentry->d_name.name); - dput(file->f_path.dentry); - path_put(&file->f_path); -} - -static void probe_subsys_eventb(void *ignore) -{ - printk(KERN_INFO "Event B is encountered\n"); -} - -static int __init tp_sample_trace_init(void) -{ - int ret; - - ret = register_trace_subsys_event(probe_subsys_event, NULL); - WARN_ON(ret); - ret = register_trace_subsys_eventb(probe_subsys_eventb, NULL); - WARN_ON(ret); - - return 0; -} - -module_init(tp_sample_trace_init); - -static void __exit tp_sample_trace_exit(void) -{ - unregister_trace_subsys_eventb(probe_subsys_eventb, NULL); - unregister_trace_subsys_event(probe_subsys_event, NULL); - tracepoint_synchronize_unregister(); -} - -module_exit(tp_sample_trace_exit); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Mathieu Desnoyers"); -MODULE_DESCRIPTION("Tracepoint Probes Samples"); diff --git a/samples/tracepoints/tracepoint-probe-sample2.c b/samples/tracepoints/tracepoint-probe-sample2.c deleted file mode 100644 index 9fcf990..0000000 --- a/samples/tracepoints/tracepoint-probe-sample2.c +++ /dev/null @@ -1,44 +0,0 @@ -/* - * tracepoint-probe-sample2.c - * - * 2nd sample tracepoint probes. - */ - -#include -#include -#include "tp-samples-trace.h" - -/* - * Here the caller only guarantees locking for struct file and struct inode. - * Locking must therefore be done in the probe to use the dentry. - */ -static void probe_subsys_event(void *ignore, - struct inode *inode, struct file *file) -{ - printk(KERN_INFO "Event is encountered with inode number %lu\n", - inode->i_ino); -} - -static int __init tp_sample_trace_init(void) -{ - int ret; - - ret = register_trace_subsys_event(probe_subsys_event, NULL); - WARN_ON(ret); - - return 0; -} - -module_init(tp_sample_trace_init); - -static void __exit tp_sample_trace_exit(void) -{ - unregister_trace_subsys_event(probe_subsys_event, NULL); - tracepoint_synchronize_unregister(); -} - -module_exit(tp_sample_trace_exit); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Mathieu Desnoyers"); -MODULE_DESCRIPTION("Tracepoint Probes Samples"); diff --git a/samples/tracepoints/tracepoint-sample.c b/samples/tracepoints/tracepoint-sample.c deleted file mode 100644 index f4d89e0..0000000 --- a/samples/tracepoints/tracepoint-sample.c +++ /dev/null @@ -1,57 +0,0 @@ -/* tracepoint-sample.c - * - * Executes a tracepoint when /proc/tracepoint-sample is opened. - * - * (C) Copyright 2007 Mathieu Desnoyers - * - * This file is released under the GPLv2. - * See the file COPYING for more details. - */ - -#include -#include -#include -#include "tp-samples-trace.h" - -DEFINE_TRACE(subsys_event); -DEFINE_TRACE(subsys_eventb); - -struct proc_dir_entry *pentry_sample; - -static int my_open(struct inode *inode, struct file *file) -{ - int i; - - trace_subsys_event(inode, file); - for (i = 0; i < 10; i++) - trace_subsys_eventb(); - return -EPERM; -} - -static const struct file_operations mark_ops = { - .open = my_open, - .llseek = noop_llseek, -}; - -static int __init sample_init(void) -{ - printk(KERN_ALERT "sample init\n"); - pentry_sample = proc_create("tracepoint-sample", 0444, NULL, - &mark_ops); - if (!pentry_sample) - return -EPERM; - return 0; -} - -static void __exit sample_exit(void) -{ - printk(KERN_ALERT "sample exit\n"); - remove_proc_entry("tracepoint-sample", NULL); -} - -module_init(sample_init) -module_exit(sample_exit) - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Mathieu Desnoyers"); -MODULE_DESCRIPTION("Tracepoint sample");