nfsd4: hash lockowners to simplify RELEASE_LOCKOWNER

Hash lockowners on just the owner string rather than on (owner, inode).
This makes the owner-string lookup needed for RELEASE_LOCKOWNER simpler
(currently it's doing at a linear search through the entire hash
table!).  That may come at the expense of making (owner, inode) lookups
more expensive if a client reuses the same lockowner across multiple
files.  We might add a separate lookup for that.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
J. Bruce Fields 2011-11-07 16:58:18 -05:00
parent c7e8472cf8
commit 06f1f864d4

View file

@ -3746,15 +3746,6 @@ last_byte_offset(u64 start, u64 len)
return end > start ? end - 1: NFS4_MAX_UINT64;
}
static inline unsigned int
lock_ownerstr_hashval(struct inode *inode, u32 cl_id,
struct xdr_netobj *ownername)
{
return (file_hashval(inode) + cl_id
+ opaque_hashval(ownername->data, ownername->len))
& LOCK_HASH_MASK;
}
static struct list_head lock_ownerstr_hashtbl[LOCK_HASH_SIZE];
/*
@ -3824,7 +3815,7 @@ static struct nfs4_lockowner *
find_lockowner_str(struct inode *inode, clientid_t *clid,
struct xdr_netobj *owner)
{
unsigned int hashval = lock_ownerstr_hashval(inode, clid->cl_id, owner);
unsigned int hashval = open_ownerstr_hashval(clid->cl_id, owner);
struct nfs4_lockowner *lo;
struct nfs4_stateowner *op;
@ -3847,7 +3838,7 @@ static void hash_lockowner(struct nfs4_lockowner *lo, unsigned int strhashval, s
* Called in nfsd4_lock - therefore, OPEN and OPEN_CONFIRM (if needed) has
* occurred.
*
* strhashval = lock_ownerstr_hashval
* strhashval = open_ownerstr_hashval
*/
static struct nfs4_lockowner *
@ -3922,7 +3913,7 @@ __be32 lookup_or_create_lock_state(struct nfsd4_compound_state *cstate, struct n
struct nfs4_ol_stateid, st_perstateowner);
return nfs_ok;
}
strhashval = lock_ownerstr_hashval(fi->fi_inode, cl->cl_clientid.cl_id,
strhashval = open_ownerstr_hashval(cl->cl_clientid.cl_id,
&lock->v.new.owner);
lo = alloc_init_lock_stateowner(strhashval, cl, ost, lock);
if (lo == NULL)
@ -4286,7 +4277,7 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp,
struct nfs4_ol_stateid *stp;
struct xdr_netobj *owner = &rlockowner->rl_owner;
struct list_head matches;
int i;
unsigned int hashval = open_ownerstr_hashval(clid->cl_id, owner);
__be32 status;
dprintk("nfsd4_release_lockowner clientid: (%08x/%08x):\n",
@ -4301,22 +4292,17 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp,
nfs4_lock_state();
status = nfserr_locks_held;
/* XXX: we're doing a linear search through all the lockowners.
* Yipes! For now we'll just hope clients aren't really using
* release_lockowner much, but eventually we have to fix these
* data structures. */
INIT_LIST_HEAD(&matches);
for (i = 0; i < LOCK_HASH_SIZE; i++) {
list_for_each_entry(sop, &lock_ownerstr_hashtbl[i], so_strhash) {
if (!same_owner_str(sop, owner, clid))
continue;
list_for_each_entry(stp, &sop->so_stateids,
st_perstateowner) {
lo = lockowner(sop);
if (check_for_locks(stp->st_file, lo))
goto out;
list_add(&lo->lo_list, &matches);
}
list_for_each_entry(sop, &lock_ownerstr_hashtbl[hashval], so_strhash) {
if (!same_owner_str(sop, owner, clid))
continue;
list_for_each_entry(stp, &sop->so_stateids,
st_perstateowner) {
lo = lockowner(sop);
if (check_for_locks(stp->st_file, lo))
goto out;
list_add(&lo->lo_list, &matches);
}
}
/* Clients probably won't expect us to return with some (but not all)