From: "J. Bruce Fields" <bfields@xxxxxxxxxx>
synchronize_rcu() gets called multiple times each time a client is
destroyed. If the laundromat thread has a lot of clients to destroy,
the delay can be noticeable. This was causing pynfs test RENEW3 to
fail.
We could embed an rcu_head in each inode and do the kref_put in an rcu
callback. But simplest is just to take a lock here.
(I also wonder if the laundromat thread would be better replaced by a
bunch of scheduled work or timers or something.)
Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx>
---
fs/nfsd/nfsctl.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 928a0b2c05dc..b14f825c62fe 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -1215,11 +1215,9 @@ static void clear_ncl(struct inode *inode)
struct nfsdfs_client *ncl = inode->i_private;
inode->i_private = NULL;
- synchronize_rcu();
kref_put(&ncl->cl_ref, ncl->cl_release);
}
-
static struct nfsdfs_client *__get_nfsdfs_client(struct inode *inode)
{
struct nfsdfs_client *nc = inode->i_private;
@@ -1233,9 +1231,9 @@ struct nfsdfs_client *get_nfsdfs_client(struct inode *inode)
{
struct nfsdfs_client *nc;
- rcu_read_lock();
+ inode_lock_shared(inode);
nc = __get_nfsdfs_client(inode);
- rcu_read_unlock();
+ inode_unlock_shared(inode);
return nc;
}
/* from __rpc_unlink */
--
2.21.0
