no need for list_for_each_entry_safe()/resetting with superblock list

just delay __put_super() a bit

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 28 insertions, 20 deletions

diff --git a/fs/dcache.c b/fs/dcache.c
index caf08574982f..9f2c13417969 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -536,7 +536,7 @@ restart:
  */
 static void prune_dcache(int count)
 {
-        struct super_block *sb, *n;
+        struct super_block *sb, *p = NULL;
         int w_count;
         int unused = dentry_stat.nr_unused;
         int prune_ratio;
@@ -550,7 +550,7 @@ static void prune_dcache(int count)
         else
                 prune_ratio = unused / count;
         spin_lock(&sb_lock);
-        list_for_each_entry_safe(sb, n, &super_blocks, s_list) {
+        list_for_each_entry(sb, &super_blocks, s_list) {
                 if (list_empty(&sb->s_instances))
                         continue;
                 if (sb->s_nr_dentry_unused == 0)
@@ -590,14 +590,16 @@ static void prune_dcache(int count)
                         up_read(&sb->s_umount);
                 }
                 spin_lock(&sb_lock);
-                /* lock was dropped, must reset next */
-                list_safe_reset_next(sb, n, s_list);
+                if (p)
+                        __put_super(p);
                 count -= pruned;
-                __put_super(sb);
+                p = sb;
                 /* more work left to do? */
                 if (count <= 0)
                         break;
         }
+        if (p)
+                __put_super(p);
         spin_unlock(&sb_lock);
         spin_unlock(&dcache_lock);
 }
diff --git a/fs/super.c b/fs/super.c
index bd9eea4bb2bb..9674ab2c8718 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -363,10 +363,10 @@ EXPORT_SYMBOL(drop_super);
  */
 void sync_supers(void)
 {
-        struct super_block *sb, *n;
+        struct super_block *sb, *p = NULL;
 
         spin_lock(&sb_lock);
-        list_for_each_entry_safe(sb, n, &super_blocks, s_list) {
+        list_for_each_entry(sb, &super_blocks, s_list) {
                 if (list_empty(&sb->s_instances))
                         continue;
                 if (sb->s_op->write_super && sb->s_dirt) {
@@ -379,11 +379,13 @@ void sync_supers(void)
                         up_read(&sb->s_umount);
 
                         spin_lock(&sb_lock);
-                        /* lock was dropped, must reset next */
-                        list_safe_reset_next(sb, n, s_list);
-                        __put_super(sb);
+                        if (p)
+                                __put_super(p);
+                        p = sb;
                 }
         }
+        if (p)
+                __put_super(p);
         spin_unlock(&sb_lock);
 }
 
@@ -397,10 +399,10 @@ void sync_supers(void)
  */
 void iterate_supers(void (*f)(struct super_block *, void *), void *arg)
 {
-        struct super_block *sb, *n;
+        struct super_block *sb, *p = NULL;
 
         spin_lock(&sb_lock);
-        list_for_each_entry_safe(sb, n, &super_blocks, s_list) {
+        list_for_each_entry(sb, &super_blocks, s_list) {
                 if (list_empty(&sb->s_instances))
                         continue;
                 sb->s_count++;
@@ -412,10 +414,12 @@ void iterate_supers(void (*f)(struct super_block *, void *), void *arg)
                 up_read(&sb->s_umount);
 
                 spin_lock(&sb_lock);
-                /* lock was dropped, must reset next */
-                list_safe_reset_next(sb, n, s_list);
-                __put_super(sb);
+                if (p)
+                        __put_super(p);
+                p = sb;
         }
+        if (p)
+                __put_super(p);
         spin_unlock(&sb_lock);
 }
 
@@ -577,10 +581,10 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force)
 
 static void do_emergency_remount(struct work_struct *work)
 {
-        struct super_block *sb, *n;
+        struct super_block *sb, *p = NULL;
 
         spin_lock(&sb_lock);
-        list_for_each_entry_safe(sb, n, &super_blocks, s_list) {
+        list_for_each_entry(sb, &super_blocks, s_list) {
                 if (list_empty(&sb->s_instances))
                         continue;
                 sb->s_count++;
@@ -594,10 +598,12 @@ static void do_emergency_remount(struct work_struct *work)
                 }
                 up_write(&sb->s_umount);
                 spin_lock(&sb_lock);
-                /* lock was dropped, must reset next */
-                list_safe_reset_next(sb, n, s_list);
-                __put_super(sb);
+                if (p)
+                        __put_super(p);
+                p = sb;
         }
+        if (p)
+                __put_super(p);
         spin_unlock(&sb_lock);
         kfree(work);
         printk("Emergency Remount complete\n");