Reduce the time spent locking the rpc_sequence structure by queuing the
nfs_seqid only when we are ready to take the lock (when calling
nfs_wait_on_sequence).
Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/nfs4proc.c | 30 +++++++++++-------------------
fs/nfs/nfs4state.c | 32 ++++++++++++++++----------------
2 files changed, 27 insertions(+), 35 deletions(-)
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 9e2e1c7..a51a753 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3331,15 +3331,12 @@ static struct nfs4_lockdata *nfs4_alloc_lockdata(struct file_lock *fl,
p->arg.fh = NFS_FH(inode);
p->arg.fl = &p->fl;
- if (!(lsp->ls_seqid.flags & NFS_SEQID_CONFIRMED)) {
- p->arg.open_seqid = nfs_alloc_seqid(&lsp->ls_state->owner->so_seqid);
- if (p->arg.open_seqid == NULL)
- goto out_free;
-
- }
+ p->arg.open_seqid = nfs_alloc_seqid(&lsp->ls_state->owner->so_seqid);
+ if (p->arg.open_seqid == NULL)
+ goto out_free;
p->arg.lock_seqid = nfs_alloc_seqid(&lsp->ls_seqid);
if (p->arg.lock_seqid == NULL)
- goto out_free;
+ goto out_free_seqid;
p->arg.lock_stateid = &lsp->ls_stateid;
p->arg.lock_owner.clientid = server->nfs_client->cl_clientid;
p->arg.lock_owner.id = lsp->ls_id.id;
@@ -3348,9 +3345,9 @@ static struct nfs4_lockdata *nfs4_alloc_lockdata(struct file_lock *fl,
p->ctx = get_nfs_open_context(ctx);
memcpy(&p->fl, fl, sizeof(p->fl));
return p;
+out_free_seqid:
+ nfs_free_seqid(p->arg.open_seqid);
out_free:
- if (p->arg.open_seqid != NULL)
- nfs_free_seqid(p->arg.open_seqid);
kfree(p);
return NULL;
}
@@ -3368,20 +3365,16 @@ static void nfs4_lock_prepare(struct rpc_task *task, void *calldata)
};
dprintk("%s: begin!\n", __FUNCTION__);
+ if (nfs_wait_on_sequence(data->arg.lock_seqid, task) != 0)
+ return;
/* Do we need to do an open_to_lock_owner? */
if (!(data->arg.lock_seqid->sequence->flags & NFS_SEQID_CONFIRMED)) {
if (nfs_wait_on_sequence(data->arg.open_seqid, task) != 0)
return;
data->arg.open_stateid = &state->stateid;
data->arg.new_lock_owner = 1;
- /* Retest in case we raced... */
- if (!(data->arg.lock_seqid->sequence->flags & NFS_SEQID_CONFIRMED))
- goto do_rpc;
- }
- if (nfs_wait_on_sequence(data->arg.lock_seqid, task) != 0)
- return;
- data->arg.new_lock_owner = 0;
-do_rpc:
+ } else
+ data->arg.new_lock_owner = 0;
data->timestamp = jiffies;
rpc_call_setup(task, &msg, 0);
dprintk("%s: done!, ret = %d\n", __FUNCTION__, data->rpc_status);
@@ -3419,6 +3412,7 @@ static void nfs4_lock_release(void *calldata)
struct nfs4_lockdata *data = calldata;
dprintk("%s: begin!\n", __FUNCTION__);
+ nfs_free_seqid(data->arg.open_seqid);
if (data->cancelled != 0) {
struct rpc_task *task;
task = nfs4_do_unlck(&data->fl, data->ctx, data->lsp,
@@ -3428,8 +3422,6 @@ static void nfs4_lock_release(void *calldata)
dprintk("%s: cancelling lock!\n", __FUNCTION__);
} else
nfs_free_seqid(data->arg.lock_seqid);
- if (data->arg.open_seqid != NULL)
- nfs_free_seqid(data->arg.open_seqid);
nfs4_put_lock_state(data->lsp);
put_nfs_open_context(data->ctx);
kfree(data);
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 5a39c6f..bf94c6e 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -644,27 +644,26 @@ void nfs4_copy_stateid(nfs4_stateid *dst, struct nfs4_state *state, fl_owner_t f
struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
{
- struct rpc_sequence *sequence = counter->sequence;
struct nfs_seqid *new;
new = kmalloc(sizeof(*new), GFP_KERNEL);
if (new != NULL) {
new->sequence = counter;
- spin_lock(&sequence->lock);
- list_add_tail(&new->list, &sequence->list);
- spin_unlock(&sequence->lock);
+ INIT_LIST_HEAD(&new->list);
}
return new;
}
void nfs_free_seqid(struct nfs_seqid *seqid)
{
- struct rpc_sequence *sequence = seqid->sequence->sequence;
+ if (!list_empty(&seqid->list)) {
+ struct rpc_sequence *sequence = seqid->sequence->sequence;
- spin_lock(&sequence->lock);
- list_del(&seqid->list);
- spin_unlock(&sequence->lock);
- rpc_wake_up(&sequence->wait);
+ spin_lock(&sequence->lock);
+ list_del(&seqid->list);
+ spin_unlock(&sequence->lock);
+ rpc_wake_up(&sequence->wait);
+ }
kfree(seqid);
}
@@ -675,6 +674,7 @@ void nfs_free_seqid(struct nfs_seqid *seqid)
*/
static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
{
+ BUG_ON(list_first_entry(&seqid->sequence->sequence->list, struct nfs_seqid, list) != seqid);
switch (status) {
case 0:
break;
@@ -726,15 +726,15 @@ int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
struct rpc_sequence *sequence = seqid->sequence->sequence;
int status = 0;
- if (sequence->list.next == &seqid->list)
- goto out;
spin_lock(&sequence->lock);
- if (sequence->list.next != &seqid->list) {
- rpc_sleep_on(&sequence->wait, task, NULL, NULL);
- status = -EAGAIN;
- }
+ if (list_empty(&seqid->list))
+ list_add_tail(&seqid->list, &sequence->list);
+ if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
+ goto unlock;
+ rpc_sleep_on(&sequence->wait, task, NULL, NULL);
+ status = -EAGAIN;
+unlock:
spin_unlock(&sequence->lock);
-out:
return status;
}