mbcache: fix shrinker function return value
The shrinker function is supposed to return the number of cache
entries after shrinking, not before shrinking. Fix that.
Based on a patch from Wang Sheng-Hui <crosslonelyover@gmail.com>.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/mbcache.c b/fs/mbcache.c
index 8a2cbd8..cf4e6cd 100644
--- a/fs/mbcache.c
+++ b/fs/mbcache.c
@@ -176,22 +176,12 @@
mb_cache_shrink_fn(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
{
LIST_HEAD(free_list);
- struct list_head *l, *ltmp;
+ struct mb_cache *cache;
+ struct mb_cache_entry *entry, *tmp;
int count = 0;
- spin_lock(&mb_cache_spinlock);
- list_for_each(l, &mb_cache_list) {
- struct mb_cache *cache =
- list_entry(l, struct mb_cache, c_cache_list);
- mb_debug("cache %s (%d)", cache->c_name,
- atomic_read(&cache->c_entry_count));
- count += atomic_read(&cache->c_entry_count);
- }
mb_debug("trying to free %d entries", nr_to_scan);
- if (nr_to_scan == 0) {
- spin_unlock(&mb_cache_spinlock);
- goto out;
- }
+ spin_lock(&mb_cache_spinlock);
while (nr_to_scan-- && !list_empty(&mb_cache_lru_list)) {
struct mb_cache_entry *ce =
list_entry(mb_cache_lru_list.next,
@@ -199,12 +189,15 @@
list_move_tail(&ce->e_lru_list, &free_list);
__mb_cache_entry_unhash(ce);
}
- spin_unlock(&mb_cache_spinlock);
- list_for_each_safe(l, ltmp, &free_list) {
- __mb_cache_entry_forget(list_entry(l, struct mb_cache_entry,
- e_lru_list), gfp_mask);
+ list_for_each_entry(cache, &mb_cache_list, c_cache_list) {
+ mb_debug("cache %s (%d)", cache->c_name,
+ atomic_read(&cache->c_entry_count));
+ count += atomic_read(&cache->c_entry_count);
}
-out:
+ spin_unlock(&mb_cache_spinlock);
+ list_for_each_entry_safe(entry, tmp, &free_list, e_lru_list) {
+ __mb_cache_entry_forget(entry, gfp_mask);
+ }
return (count / 100) * sysctl_vfs_cache_pressure;
}