From: "Jose R. Santos" Subject: Re: [PATCH][RFC] JBD2: Use DebugFS for jbd2 debug config option. Date: Fri, 8 Jun 2007 22:57:41 -0500 Message-ID: <20070608225741.58dc7459@gara> References: <20070607234537.56537f85@gara> <20070608070812.GE5181@schatzie.adilger.int> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: linux-ext4@vger.kernel.org To: Andreas Dilger Return-path: Received: from e32.co.us.ibm.com ([32.97.110.150]:49203 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750902AbXFID6S (ORCPT ); Fri, 8 Jun 2007 23:58:18 -0400 Received: from d03relay02.boulder.ibm.com (d03relay02.boulder.ibm.com [9.17.195.227]) by e32.co.us.ibm.com (8.12.11.20060308/8.13.8) with ESMTP id l593riW0011760 for ; Fri, 8 Jun 2007 23:53:44 -0400 Received: from d03av01.boulder.ibm.com (d03av01.boulder.ibm.com [9.17.195.167]) by d03relay02.boulder.ibm.com (8.13.8/8.13.8/NCO v8.3) with ESMTP id l593w2KL210616 for ; Fri, 8 Jun 2007 21:58:07 -0600 Received: from d03av01.boulder.ibm.com (loopback [127.0.0.1]) by d03av01.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id l593w2A2021413 for ; Fri, 8 Jun 2007 21:58:02 -0600 In-Reply-To: <20070608070812.GE5181@schatzie.adilger.int> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Fri, 8 Jun 2007 01:08:12 -0600 Andreas Dilger wrote: > On Jun 07, 2007 23:45 -0500, Jose R. Santos wrote: > > The jbd2-debug file used to be located in /proc/sys/fs/jbd2-debug, but > > create_proc_entry() does not do lookups on file names with more that one > > directory deep. This causes the entry creation to fail and hence, no proc > > file is created. This patch moves the file to /proc/jbd2-degug. > > > > The file could be move to /proc/fs/jbd2/jbd2-debug, but it would require > > some minor alterations to the jbd-stats patch. > > I don't think we really want to be adding top-level files in /proc. > What about using the "debugfs" filesystem (not to be confused with > the e2fsprogs 'debugfs' command)? How about this then? Moved the file to use debugfs as well as having the nice effect of removing more lines than what it adds. Signed-off-by: Jose R. Santos --- fs/jbd2/journal.c | 62 20 + 42 - 0 ! include/linux/jbd2.h | 2 1 + 1 - 0 ! 2 files changed, 21 insertions(+), 43 deletions(-) Index: linux-2.6.22-rc4/fs/jbd2/journal.c =================================================================== --- linux-2.6.22-rc4.orig/fs/jbd2/journal.c 2007-06-08 15:03:14.353372404 -0500 +++ linux-2.6.22-rc4/fs/jbd2/journal.c 2007-06-08 22:44:04.476375738 -0500 @@ -36,6 +36,7 @@ #include #include #include +#include #include #include @@ -2256,60 +2257,37 @@ void jbd2_journal_put_journal_head(struc * /proc tunables */ #if defined(CONFIG_JBD2_DEBUG) -int jbd2_journal_enable_debug; +u16 jbd2_journal_enable_debug; EXPORT_SYMBOL(jbd2_journal_enable_debug); #endif -#if defined(CONFIG_JBD2_DEBUG) && defined(CONFIG_PROC_FS) +#if defined(CONFIG_JBD2_DEBUG) && defined(CONFIG_DEBUG_FS) -static struct proc_dir_entry *proc_jbd_debug; +#define JBD2_DEBUG_NAME "jbd2-debug" -static int read_jbd_debug(char *page, char **start, off_t off, - int count, int *eof, void *data) -{ - int ret; - - ret = sprintf(page + off, "%d\n", jbd2_journal_enable_debug); - *eof = 1; - return ret; -} +struct dentry *jbd2_debugfs_dir, *jbd2_debug; -static int write_jbd_debug(struct file *file, const char __user *buffer, - unsigned long count, void *data) +static void __init jbd2_create_debugfs_entry(void) { - char buf[32]; - - if (count > ARRAY_SIZE(buf) - 1) - count = ARRAY_SIZE(buf) - 1; - if (copy_from_user(buf, buffer, count)) - return -EFAULT; - buf[ARRAY_SIZE(buf) - 1] = '\0'; - jbd2_journal_enable_debug = simple_strtoul(buf, NULL, 10); - return count; -} - -#define JBD_PROC_NAME "sys/fs/jbd2-debug" - -static void __init create_jbd_proc_entry(void) -{ - proc_jbd_debug = create_proc_entry(JBD_PROC_NAME, 0644, NULL); - if (proc_jbd_debug) { - /* Why is this so hard? */ - proc_jbd_debug->read_proc = read_jbd_debug; - proc_jbd_debug->write_proc = write_jbd_debug; - } + jbd2_debugfs_dir = debugfs_create_dir("jbd2", NULL); + if (jbd2_debugfs_dir) + jbd2_debug = debugfs_create_u16(JBD2_DEBUG_NAME, S_IRUGO, + jbd2_debugfs_dir, + &jbd2_journal_enable_debug); } -static void __exit jbd2_remove_jbd_proc_entry(void) +static void __exit jbd2_remove_debugfs_entry(void) { - if (proc_jbd_debug) - remove_proc_entry(JBD_PROC_NAME, NULL); + if (jbd2_debug) + debugfs_remove(jbd2_debug); + if (jbd2_debugfs_dir) + debugfs_remove(jbd2_debugfs_dir); } #else -#define create_jbd_proc_entry() do {} while (0) -#define jbd2_remove_jbd_proc_entry() do {} while (0) +#define jbd2_create_debugfs_entry() do {} while (0) +#define jbd2_remove_debugfs_entry() do {} while (0) #endif @@ -2391,7 +2369,7 @@ static int __init journal_init(void) ret = journal_init_caches(); if (ret != 0) jbd2_journal_destroy_caches(); - create_jbd_proc_entry(); + jbd2_create_debugfs_entry(); jbd2_create_jbd_stats_proc_entry(); return ret; } @@ -2403,7 +2381,7 @@ static void __exit journal_exit(void) if (n) printk(KERN_EMERG "JBD: leaked %d journal_heads!\n", n); #endif - jbd2_remove_jbd_proc_entry(); + jbd2_remove_debugfs_entry(); jbd2_remove_jbd_stats_proc_entry(); jbd2_journal_destroy_caches(); } Index: linux-2.6.22-rc4/include/linux/jbd2.h =================================================================== --- linux-2.6.22-rc4.orig/include/linux/jbd2.h 2007-06-08 18:01:41.027527067 -0500 +++ linux-2.6.22-rc4/include/linux/jbd2.h 2007-06-08 18:02:27.351010026 -0500 @@ -57,7 +57,7 @@ * CONFIG_JBD2_DEBUG is on. */ #define JBD_EXPENSIVE_CHECKING -extern int jbd2_journal_enable_debug; +extern u16 jbd2_journal_enable_debug; #define jbd_debug(n, f, a...) \ do { \ -JRS