[Ocfs2-tools-devel] [PATCH 2/3] debugfs: Add option to limit fs_locks to dump only busy locks

[Sunil Mushran]

This patch enhances the fs_locks command in debugfs.ocfs2 to limit
the output to only the busy locks. This is useful in debugging hangs
in a cluster operation as it allows the user to limit the dump to
only the locks that could be relevant to the issue.

Signed-off-by: Sunil Mushran <sunil.mushran at oracle.com>
---
 debugfs.ocfs2/commands.c              |   14 ++++++++++----
 debugfs.ocfs2/dump_fs_locks.c         |   22 ++++++++++++++--------
 debugfs.ocfs2/include/dump_fs_locks.h |    4 ++--
 3 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/debugfs.ocfs2/commands.c b/debugfs.ocfs2/commands.c
index cdab387..c06442c 100644
--- a/debugfs.ocfs2/commands.c
+++ b/debugfs.ocfs2/commands.c
@@ -801,7 +801,7 @@ static void do_help (char **args)
 	printf ("encode <filespec>\t\t\tShow lock name\n");
 	printf ("extent <block#>\t\t\t\tShow extent block\n");
 	printf ("findpath <block#>\t\t\tList one pathname of the inode/lockname\n");
-	printf ("fs_locks [-l]\t\t\t\tShow live fs locking state\n");
+	printf ("fs_locks [-l] [-B]\t\t\tShow live fs locking state\n");
 	printf ("group <block#>\t\t\t\tShow chain group\n");
 	printf ("hb\t\t\t\t\tShows the used heartbeat blocks\n");
 	printf ("help, ?\t\t\t\t\tThis information\n");
@@ -1469,15 +1469,21 @@ static void do_fs_locks(char **args)
 {
 	FILE *out;
 	int dump_lvbs = 0;
+	int only_busy = 0;
+	int i = 0;
 
 	if (check_device_open())
 		return;
 
-	if (args[1] && !strcmp("-l", args[1]))
-		dump_lvbs = 1;
+	while (args[++i]) {
+		if (!strcmp("-l", args[i]))
+			dump_lvbs = 1;
+		else if (!strcmp("-B", args[i]))
+			only_busy = 1;
+	}
 
 	out = open_pager(gbls.interactive);
-	dump_fs_locks(gbls.fs->uuid_str, out, dump_lvbs);
+	dump_fs_locks(gbls.fs->uuid_str, out, dump_lvbs, only_busy);
 	close_pager(out);
 }
 
diff --git a/debugfs.ocfs2/dump_fs_locks.c b/debugfs.ocfs2/dump_fs_locks.c
index 74423eb..28059d0 100644
--- a/debugfs.ocfs2/dump_fs_locks.c
+++ b/debugfs.ocfs2/dump_fs_locks.c
@@ -5,7 +5,7 @@
  *
  * Interface with the kernel and dump current fs locking state
  *
- * Copyright (C) 2005 Oracle.  All rights reserved.
+ * Copyright (C) 2005, 2008 Oracle.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public
@@ -21,9 +21,8 @@
  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  * Boston, MA 021110-1307, USA.
  *
- *  This code is a port of e2fsprogs/lib/ext2fs/dir_iterate.c
- *  Copyright (C) 1993, 1994, 1994, 1995, 1996, 1997 Theodore Ts'o.
  */
+
 #define _XOPEN_SOURCE 600  /* Triggers XOPEN2K in features.h */
 #define _LARGEFILE64_SOURCE
 
@@ -226,7 +225,7 @@ static void dump_meta_lvb(const char *raw_lvb, FILE *out)
 }
 
 /* 0 = eof, > 0 = success, < 0 = error */
-static int dump_version_one(FILE *file, FILE *out, int lvbs)
+static int dump_version_one(FILE *file, FILE *out, int lvbs, int only_busy)
 {
 	char id[OCFS2_LOCK_ID_MAX_LEN + 1];	
 	char lvb[DLM_LVB_LEN];
@@ -276,6 +275,13 @@ static int dump_version_one(FILE *file, FILE *out, int lvbs)
 		lvb[i] = (char) dummy;
 	}
 
+	if (only_busy) {
+		if (!(flags & OCFS2_LOCK_BUSY)) {
+			ret = 1;
+			goto out;
+		}
+	}
+
 	fprintf(out, "Lockres: %s  Mode: %s\nFlags:", id, level_str(level));
 	print_flags(flags, out);
 	fprintf(out, "\nRO Holders: %u  EX Holders: %u\n", ro, ex);
@@ -311,7 +317,7 @@ static int end_line(FILE *f)
 
 #define CURRENT_PROTO 1
 /* returns 0 on error or end of file */
-static int dump_one_lockres(FILE *file, FILE *out, int lvbs)
+static int dump_one_lockres(FILE *file, FILE *out, int lvbs, int only_busy)
 {
 	unsigned int version;
 	int ret;
@@ -326,7 +332,7 @@ static int dump_one_lockres(FILE *file, FILE *out, int lvbs)
 		return 0;
 	}
 
-	ret = dump_version_one(file, out, lvbs);
+	ret = dump_version_one(file, out, lvbs, only_busy);
 	if (ret <= 0)
 		return 0;
 
@@ -398,7 +404,7 @@ out:
 #define DEBUGFS_PATH		SYSFS_BASE "debug"
 #define DEBUGFS_ALTERNATE_PATH	"/debug"
 
-void dump_fs_locks(char *uuid_str, FILE *out, int dump_lvbs)
+void dump_fs_locks(char *uuid_str, FILE *out, int dump_lvbs, int only_busy)
 {
 	errcode_t ret;
 	int err;
@@ -425,7 +431,7 @@ void dump_fs_locks(char *uuid_str, FILE *out, int dump_lvbs)
 		return;
 	}
 
-	while (dump_one_lockres(file, out, dump_lvbs))
+	while (dump_one_lockres(file, out, dump_lvbs, only_busy))
 		;
 
 	fclose(file);
diff --git a/debugfs.ocfs2/include/dump_fs_locks.h b/debugfs.ocfs2/include/dump_fs_locks.h
index 420a6d1..f218458 100644
--- a/debugfs.ocfs2/include/dump_fs_locks.h
+++ b/debugfs.ocfs2/include/dump_fs_locks.h
@@ -3,7 +3,7 @@
  *
  * Function prototypes, macros, etc. for related 'C' files
  *
- * Copyright (C) 2005 Oracle.  All rights reserved.
+ * Copyright (C) 2005, 2008 Oracle.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public
@@ -25,6 +25,6 @@
 #ifndef _DUMP_FS_LOCKS_H_
 #define _DUMP_FS_LOCKS_H_
 
-void dump_fs_locks(char *uuid, FILE *out, int dump_lvbs);
+void dump_fs_locks(char *uuid, FILE *out, int dump_lvbs, int only_busy);
 
 #endif		/* _DUMP_FS_LOCKS_H_ */
-- 
1.5.2.5