NFS: Don't call iput() in nfs_access_cache_shrinker

iput() can potentially attempt to allocate memory, so we should avoid
calling it in a memory shrinker. Instead, rely on the fact that iput() will
call nfs_access_zap_cache().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2010-05-13 12:51:06 -04:00
parent 1a81bb8a1f
commit 9c7e7e2337

View file

@ -1716,22 +1716,14 @@ int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask)
if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
return (nr_to_scan == 0) ? 0 : -1;
restart:
spin_lock(&nfs_access_lru_lock);
list_for_each_entry(nfsi, &nfs_access_lru_list, access_cache_inode_lru) {
struct rw_semaphore *s_umount;
struct inode *inode;
if (nr_to_scan-- == 0)
break;
s_umount = &nfsi->vfs_inode.i_sb->s_umount;
if (!down_read_trylock(s_umount))
continue;
inode = igrab(&nfsi->vfs_inode);
if (inode == NULL) {
up_read(s_umount);
continue;
}
inode = &nfsi->vfs_inode;
spin_lock(&inode->i_lock);
if (list_empty(&nfsi->access_cache_entry_lru))
goto remove_lru_entry;
@ -1745,13 +1737,10 @@ int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask)
else {
remove_lru_entry:
list_del_init(&nfsi->access_cache_inode_lru);
smp_mb__before_clear_bit();
clear_bit(NFS_INO_ACL_LRU_SET, &nfsi->flags);
smp_mb__after_clear_bit();
}
spin_unlock(&inode->i_lock);
spin_unlock(&nfs_access_lru_lock);
iput(inode);
up_read(s_umount);
goto restart;
}
spin_unlock(&nfs_access_lru_lock);
nfs_access_free_list(&head);