NFSv4.1: Convert pNFS deviceid to use kfree_rcu()

Use of synchronize_rcu() when unmounting and potentially freeing a lot
of deviceids is problematic. There really is no reason why we can't just
use kfree_rcu() here.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Trond Myklebust 2015-03-09 15:23:35 -04:00
parent 2854475f6c
commit 84a80f62f7
6 changed files with 7 additions and 8 deletions

View File

@ -33,7 +33,7 @@ bl_free_deviceid_node(struct nfs4_deviceid_node *d)
container_of(d, struct pnfs_block_dev, node);
bl_free_device(dev);
kfree(dev);
kfree_rcu(dev, node.rcu);
}
static int

View File

@ -55,7 +55,7 @@ nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
nfs4_pnfs_ds_put(ds);
}
kfree(dsaddr->stripe_indices);
kfree(dsaddr);
kfree_rcu(dsaddr, id_node.rcu);
}
/* Decode opaque device data and return the result */

View File

@ -30,7 +30,7 @@ void nfs4_ff_layout_free_deviceid(struct nfs4_ff_layout_ds *mirror_ds)
{
nfs4_print_deviceid(&mirror_ds->id_node.deviceid);
nfs4_pnfs_ds_put(mirror_ds->ds);
kfree(mirror_ds);
kfree_rcu(mirror_ds, id_node.rcu);
}
/* Decode opaque device data and construct new_ds using it */

View File

@ -57,7 +57,7 @@ objio_free_deviceid_node(struct nfs4_deviceid_node *d)
dprintk("%s: free od=%p\n", __func__, de->od.od);
osduld_put_device(de->od.od);
kfree(de);
kfree_rcu(d, rcu);
}
struct objio_segment {

View File

@ -302,6 +302,7 @@ struct nfs4_deviceid_node {
unsigned long flags;
unsigned long timestamp_unavailable;
struct nfs4_deviceid deviceid;
struct rcu_head rcu;
atomic_t ref;
};

View File

@ -175,8 +175,8 @@ __nfs4_find_get_deviceid(struct nfs_server *server,
rcu_read_lock();
d = _lookup_deviceid(server->pnfs_curr_ld, server->nfs_client, id,
hash);
if (d != NULL)
atomic_inc(&d->ref);
if (d != NULL && !atomic_inc_not_zero(&d->ref))
d = NULL;
rcu_read_unlock();
return d;
}
@ -236,7 +236,6 @@ nfs4_delete_deviceid(const struct pnfs_layoutdriver_type *ld,
}
hlist_del_init_rcu(&d->node);
spin_unlock(&nfs4_deviceid_lock);
synchronize_rcu();
/* balance the initial ref set in pnfs_insert_deviceid */
if (atomic_dec_and_test(&d->ref))
@ -321,7 +320,6 @@ _deviceid_purge_client(const struct nfs_client *clp, long hash)
if (hlist_empty(&tmp))
return;
synchronize_rcu();
while (!hlist_empty(&tmp)) {
d = hlist_entry(tmp.first, struct nfs4_deviceid_node, tmpnode);
hlist_del(&d->tmpnode);