UBIFS: lessen the size of debugging info data structure
This patch lessens the 'struct ubifs_debug_info' size by 90 bytes by
allocating less bytes for the debugfs root directory name. It introduces macros
for the name patter an length instead of hard-coding 100 bytes. It also makes
UBIFS use 'snprintf()' and teaches it to gracefully catch situations when the
name array is too short.
Additionally, this patch makes 2 unrelated changes - I just thought they do not
deserve separate commits: simplifies 'ubifs_assert()' for non-debugging case
and makes 'dbg_debugfs_init()' properly verify debugfs return code which may be
an error code or NULL, so we should you 'IS_ERR_OR_NULL()' instead of
'IS_ERR()'.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index a811ac4..b59c43a 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -33,6 +33,13 @@
#include <linux/random.h>
+/*
+ * The UBIFS debugfs directory name pattern and maximum name length (3 for "ubi"
+ * + 1 for "_" and plus 2x2 for 2 UBI numbers and 1 for the trailing zero byte.
+ */
+#define UBIFS_DFS_DIR_NAME "ubi%d_%d"
+#define UBIFS_DFS_DIR_LEN (3 + 1 + 2*2 + 1)
+
/**
* ubifs_debug_info - per-FS debugging information.
* @old_zroot: old index root - used by 'dbg_check_old_index()'
@@ -84,7 +91,7 @@
long long saved_free;
int saved_idx_gc_cnt;
- char dfs_dir_name[100];
+ char dfs_dir_name[UBIFS_DFS_DIR_LEN + 1];
struct dentry *dfs_dir;
struct dentry *dfs_dump_lprops;
struct dentry *dfs_dump_budg;
@@ -313,7 +320,7 @@
/* Use "if (0)" to make compiler check arguments even if debugging is off */
#define ubifs_assert(expr) do { \
- if (0 && (expr)) \
+ if (0) \
printk(KERN_CRIT "UBIFS assert failed in %s at %u (pid %d)\n", \
__func__, __LINE__, current->pid); \
} while (0)