Commit 8b671b80 authored by J. Bruce Fields's avatar J. Bruce Fields

nfsd4: remove use of mutex for file_hashtable

As part of reducing the scope of the client_mutex, and in order to
remove the need for mutexes from the callback code (so that callbacks
can be done as asynchronous rpc calls), move manipulations of the
file_hashtable under the recall_lock.

Update the relevant comments while we're here.
Signed-off-by: default avatarJ. Bruce Fields <bfields@citi.umich.edu>
Cc: Alexandros Batsakis <batsakis@netapp.com>
Reviewed-by: default avatarBenny Halevy <bhalevy@panasas.com>
parent d7fdcfe0
...@@ -491,8 +491,6 @@ nfsd4_cb_recall(struct nfs4_delegation *dp) ...@@ -491,8 +491,6 @@ nfsd4_cb_recall(struct nfs4_delegation *dp)
* or deleg_return. * or deleg_return.
*/ */
put_nfs4_client(clp); put_nfs4_client(clp);
nfs4_lock_state();
nfs4_put_delegation(dp); nfs4_put_delegation(dp);
nfs4_unlock_state();
return; return;
} }
...@@ -78,14 +78,18 @@ static struct nfs4_delegation * find_delegation_stateid(struct inode *ino, state ...@@ -78,14 +78,18 @@ static struct nfs4_delegation * find_delegation_stateid(struct inode *ino, state
static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery"; static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
static void nfs4_set_recdir(char *recdir); static void nfs4_set_recdir(char *recdir);
/* Locking: /* Locking: */
*
* client_mutex: /* Currently used for almost all code touching nfsv4 state: */
* protects clientid_hashtbl[], clientstr_hashtbl[],
* unconfstr_hashtbl[], uncofid_hashtbl[].
*/
static DEFINE_MUTEX(client_mutex); static DEFINE_MUTEX(client_mutex);
/*
* Currently used for the del_recall_lru and file hash table. In an
* effort to decrease the scope of the client_mutex, this spinlock may
* eventually cover more:
*/
static DEFINE_SPINLOCK(recall_lock);
static struct kmem_cache *stateowner_slab = NULL; static struct kmem_cache *stateowner_slab = NULL;
static struct kmem_cache *file_slab = NULL; static struct kmem_cache *file_slab = NULL;
static struct kmem_cache *stateid_slab = NULL; static struct kmem_cache *stateid_slab = NULL;
...@@ -116,33 +120,23 @@ opaque_hashval(const void *ptr, int nbytes) ...@@ -116,33 +120,23 @@ opaque_hashval(const void *ptr, int nbytes)
return x; return x;
} }
/*
* Delegation state
*/
/* recall_lock protects the del_recall_lru */
static DEFINE_SPINLOCK(recall_lock);
static struct list_head del_recall_lru; static struct list_head del_recall_lru;
static void
free_nfs4_file(struct kref *kref)
{
struct nfs4_file *fp = container_of(kref, struct nfs4_file, fi_ref);
list_del(&fp->fi_hash);
iput(fp->fi_inode);
kmem_cache_free(file_slab, fp);
}
static inline void static inline void
put_nfs4_file(struct nfs4_file *fi) put_nfs4_file(struct nfs4_file *fi)
{ {
kref_put(&fi->fi_ref, free_nfs4_file); if (atomic_dec_and_lock(&fi->fi_ref, &recall_lock)) {
list_del(&fi->fi_hash);
spin_unlock(&recall_lock);
iput(fi->fi_inode);
kmem_cache_free(file_slab, fi);
}
} }
static inline void static inline void
get_nfs4_file(struct nfs4_file *fi) get_nfs4_file(struct nfs4_file *fi)
{ {
kref_get(&fi->fi_ref); atomic_inc(&fi->fi_ref);
} }
static int num_delegations; static int num_delegations;
...@@ -1000,11 +994,13 @@ alloc_init_file(struct inode *ino) ...@@ -1000,11 +994,13 @@ alloc_init_file(struct inode *ino)
fp = kmem_cache_alloc(file_slab, GFP_KERNEL); fp = kmem_cache_alloc(file_slab, GFP_KERNEL);
if (fp) { if (fp) {
kref_init(&fp->fi_ref); atomic_set(&fp->fi_ref, 1);
INIT_LIST_HEAD(&fp->fi_hash); INIT_LIST_HEAD(&fp->fi_hash);
INIT_LIST_HEAD(&fp->fi_stateids); INIT_LIST_HEAD(&fp->fi_stateids);
INIT_LIST_HEAD(&fp->fi_delegations); INIT_LIST_HEAD(&fp->fi_delegations);
spin_lock(&recall_lock);
list_add(&fp->fi_hash, &file_hashtbl[hashval]); list_add(&fp->fi_hash, &file_hashtbl[hashval]);
spin_unlock(&recall_lock);
fp->fi_inode = igrab(ino); fp->fi_inode = igrab(ino);
fp->fi_id = current_fileid++; fp->fi_id = current_fileid++;
fp->fi_had_conflict = false; fp->fi_had_conflict = false;
...@@ -1177,12 +1173,15 @@ find_file(struct inode *ino) ...@@ -1177,12 +1173,15 @@ find_file(struct inode *ino)
unsigned int hashval = file_hashval(ino); unsigned int hashval = file_hashval(ino);
struct nfs4_file *fp; struct nfs4_file *fp;
spin_lock(&recall_lock);
list_for_each_entry(fp, &file_hashtbl[hashval], fi_hash) { list_for_each_entry(fp, &file_hashtbl[hashval], fi_hash) {
if (fp->fi_inode == ino) { if (fp->fi_inode == ino) {
get_nfs4_file(fp); get_nfs4_file(fp);
spin_unlock(&recall_lock);
return fp; return fp;
} }
} }
spin_unlock(&recall_lock);
return NULL; return NULL;
} }
......
...@@ -214,7 +214,7 @@ struct nfs4_stateowner { ...@@ -214,7 +214,7 @@ struct nfs4_stateowner {
* share_acces, share_deny on the file. * share_acces, share_deny on the file.
*/ */
struct nfs4_file { struct nfs4_file {
struct kref fi_ref; atomic_t fi_ref;
struct list_head fi_hash; /* hash by "struct inode *" */ struct list_head fi_hash; /* hash by "struct inode *" */
struct list_head fi_stateids; struct list_head fi_stateids;
struct list_head fi_delegations; struct list_head fi_delegations;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment