fix prune_dcache()/umount() race

... and get rid of the last __put_super_and_need_restart() caller

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2010-03-22 20:27:55 -04:00
Родитель df40c01a92
Коммит 79893c17b4
1 изменённых файлов: 6 добавлений и 11 удалений

Просмотреть файл

@ -536,7 +536,7 @@ restart:
*/
static void prune_dcache(int count)
{
struct super_block *sb;
struct super_block *sb, *n;
int w_count;
int unused = dentry_stat.nr_unused;
int prune_ratio;
@ -545,13 +545,12 @@ static void prune_dcache(int count)
if (unused == 0 || count == 0)
return;
spin_lock(&dcache_lock);
restart:
if (count >= unused)
prune_ratio = 1;
else
prune_ratio = unused / count;
spin_lock(&sb_lock);
list_for_each_entry(sb, &super_blocks, s_list) {
list_for_each_entry_safe(sb, n, &super_blocks, s_list) {
if (list_empty(&sb->s_instances))
continue;
if (sb->s_nr_dentry_unused == 0)
@ -592,14 +591,10 @@ restart:
}
spin_lock(&sb_lock);
count -= pruned;
/*
* restart only when sb is no longer on the list and
* we have more work to do.
*/
if (__put_super_and_need_restart(sb) && count > 0) {
spin_unlock(&sb_lock);
goto restart;
}
__put_super(sb);
/* more work left to do? */
if (count <= 0)
break;
}
spin_unlock(&sb_lock);
spin_unlock(&dcache_lock);