From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761566Ab0J2Sog (ORCPT ); Fri, 29 Oct 2010 14:44:36 -0400 Received: from mail.windriver.com ([147.11.1.11]:58540 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761551Ab0J2Sof (ORCPT ); Fri, 29 Oct 2010 14:44:35 -0400 From: Jason Wessel To: torvalds@linux-foundation.org Cc: linux-kernel@vger.kernel.org, kgdb-bugreport@lists.sourceforge.net, Jason Wessel Subject: [PATCH 1/7] kdb: Add kdb kernel module sample Date: Fri, 29 Oct 2010 13:43:35 -0500 Message-Id: <1288377821-24520-2-git-send-email-jason.wessel@windriver.com> X-Mailer: git-send-email 1.6.4.rc1 In-Reply-To: <1288377821-24520-1-git-send-email-jason.wessel@windriver.com> References: <1288377821-24520-1-git-send-email-jason.wessel@windriver.com> X-OriginalArrivalTime: 29 Oct 2010 18:43:48.0269 (UTC) FILETIME=[392615D0:01CB7799] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add an example of how to add a dynamic kdb shell command via a kernel module. Signed-off-by: Jason Wessel --- Documentation/DocBook/kgdb.tmpl | 13 ++++++++- samples/Kconfig | 7 ++++ samples/Makefile | 2 +- samples/kdb/Makefile | 1 + samples/kdb/kdb_hello.c | 60 +++++++++++++++++++++++++++++++++++++++ 5 files changed, 81 insertions(+), 2 deletions(-) create mode 100644 samples/kdb/Makefile create mode 100644 samples/kdb/kdb_hello.c diff --git a/Documentation/DocBook/kgdb.tmpl b/Documentation/DocBook/kgdb.tmpl index 490d862..d71b57f 100644 --- a/Documentation/DocBook/kgdb.tmpl +++ b/Documentation/DocBook/kgdb.tmpl @@ -710,7 +710,18 @@ Task Addr Pid Parent [*] cpu State Thread Command A simple shell The kdb core command set A registration API to register additional kdb shell commands. - A good example of a self-contained kdb module is the "ftdump" command for dumping the ftrace buffer. See: kernel/trace/trace_kdb.c + + A good example of a self-contained kdb module + is the "ftdump" command for dumping the ftrace buffer. See: + kernel/trace/trace_kdb.c + For an example of how to dynamically register + a new kdb command you can build the kdb_hello.ko kernel module + from samples/kdb/kdb_hello.c. To build this example you can + set CONFIG_SAMPLES=y and CONFIG_SAMPLE_KDB=m in your kernel + config. Later run "modprobe kdb_hello" and the next time you + enter the kdb shell, you can run the "hello" + command. + The implementation for kdb_printf() which emits messages directly to I/O drivers, bypassing the kernel log. diff --git a/samples/Kconfig b/samples/Kconfig index 954a1d5..e03cf0e 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -54,4 +54,11 @@ config SAMPLE_KFIFO If in doubt, say "N" here. +config SAMPLE_KDB + tristate "Build kdb command exmaple -- loadable modules only" + depends on KGDB_KDB && m + help + Build an example of how to dynamically add the hello + command to the kdb shell. + endif # SAMPLES diff --git a/samples/Makefile b/samples/Makefile index 76b3c34..f26c095 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -1,4 +1,4 @@ # Makefile for Linux samples code obj-$(CONFIG_SAMPLES) += kobject/ kprobes/ tracepoints/ trace_events/ \ - hw_breakpoint/ kfifo/ + hw_breakpoint/ kfifo/ kdb/ diff --git a/samples/kdb/Makefile b/samples/kdb/Makefile new file mode 100644 index 0000000..fbedf39 --- /dev/null +++ b/samples/kdb/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_SAMPLE_KDB) += kdb_hello.o diff --git a/samples/kdb/kdb_hello.c b/samples/kdb/kdb_hello.c new file mode 100644 index 0000000..c1c2fa0 --- /dev/null +++ b/samples/kdb/kdb_hello.c @@ -0,0 +1,60 @@ +/* + * Created by: Jason Wessel + * + * Copyright (c) 2010 Wind River Systems, Inc. All Rights Reserved. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include +#include + +/* + * All kdb shell command call backs receive argc and argv, where + * argv[0] is the command the end user typed + */ +static int kdb_hello_cmd(int argc, const char **argv) +{ + if (argc > 1) + return KDB_ARGCOUNT; + + if (argc) + kdb_printf("Hello %s.\n", argv[1]); + else + kdb_printf("Hello world!\n"); + + return 0; +} + + +static int __init kdb_hello_cmd_init(void) +{ + /* + * Registration of a dynamically added kdb command is done with + * kdb_register() with the arguments being: + * 1: The name of the shell command + * 2: The function that processes the command + * 3: Description of the usage of any arguments + * 4: Descriptive text when you run help + * 5: Number of characters to complete the command + * 0 == type the whole command + * 1 == match both "g" and "go" for example + */ + kdb_register("hello", kdb_hello_cmd, "[string]", + "Say Hello World or Hello [string]", 0); + return 0; +} + +static void __exit kdb_hello_cmd_exit(void) +{ + kdb_unregister("hello"); +} + +module_init(kdb_hello_cmd_init); +module_exit(kdb_hello_cmd_exit); + +MODULE_AUTHOR("WindRiver"); +MODULE_DESCRIPTION("KDB example to add a hello command"); +MODULE_LICENSE("GPL"); -- 1.6.3.3