2010-01-27 18:10:59

by Alexandros Batsakis

[permalink] [raw]
Subject: [PATCH 2/4] nfs4: V2 prevent backlogging of renewd requests

Signed-off-by: Alexandros Batsakis <[email protected]>
---
fs/nfs/nfs4proc.c | 3 +++
fs/nfs/nfs4renewd.c | 24 +++++++-----------------
2 files changed, 10 insertions(+), 17 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 3644c35..9fc99e9 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3162,6 +3162,7 @@ static void nfs4_renew_done(struct rpc_task *task, void *data)
if (time_before(clp->cl_last_renewal,timestamp))
clp->cl_last_renewal = timestamp;
spin_unlock(&clp->cl_lock);
+ nfs4_schedule_state_renewal(clp);
}

static const struct rpc_call_ops nfs4_renew_ops = {
@@ -5049,6 +5050,8 @@ void nfs41_sequence_call_done(struct rpc_task *task, void *data)
}
dprintk("%s rpc_cred %p\n", __func__, task->tk_msg.rpc_cred);

+ nfs4_schedule_state_renewal(clp);
+
kfree(task->tk_msg.rpc_argp);
kfree(task->tk_msg.rpc_resp);

diff --git a/fs/nfs/nfs4renewd.c b/fs/nfs/nfs4renewd.c
index 0156c01..d87f103 100644
--- a/fs/nfs/nfs4renewd.c
+++ b/fs/nfs/nfs4renewd.c
@@ -36,11 +36,6 @@
* as an rpc_task, not a real kernel thread, so it always runs in rpciod's
* context. There is one renewd per nfs_server.
*
- * TODO: If the send queue gets backlogged (e.g., if the server goes down),
- * we will keep filling the queue with periodic RENEW requests. We need a
- * mechanism for ensuring that if renewd successfully sends off a request,
- * then it only wakes up when the request is finished. Maybe use the
- * child task framework of the RPC layer?
*/

#include <linux/mm.h>
@@ -63,7 +58,7 @@ nfs4_renew_state(struct work_struct *work)
struct nfs_client *clp =
container_of(work, struct nfs_client, cl_renewd.work);
struct rpc_cred *cred;
- long lease, timeout;
+ long lease;
unsigned long last, now;

ops = nfs4_state_renewal_ops[clp->cl_minorversion];
@@ -75,7 +70,6 @@ nfs4_renew_state(struct work_struct *work)
lease = clp->cl_lease_time;
last = clp->cl_last_renewal;
now = jiffies;
- timeout = (2 * lease) / 3 + (long)last - (long)now;
/* Are we close to a lease timeout? */
if (time_after(now, last + lease/3)) {
cred = ops->get_state_renewal_cred_locked(clp);
@@ -90,19 +84,15 @@ nfs4_renew_state(struct work_struct *work)
/* Queue an asynchronous RENEW. */
ops->sched_state_renewal(clp, cred);
put_rpccred(cred);
+ goto out_exp;
}
- timeout = (2 * lease) / 3;
- spin_lock(&clp->cl_lock);
- } else
+ } else {
dprintk("%s: failed to call renewd. Reason: lease not expired \n",
__func__);
- if (timeout < 5 * HZ) /* safeguard */
- timeout = 5 * HZ;
- dprintk("%s: requeueing work. Lease period = %ld\n",
- __func__, (timeout + HZ - 1) / HZ);
- cancel_delayed_work(&clp->cl_renewd);
- schedule_delayed_work(&clp->cl_renewd, timeout);
- spin_unlock(&clp->cl_lock);
+ spin_unlock(&clp->cl_lock);
+ }
+ nfs4_schedule_state_renewal(clp);
+out_exp:
nfs_expire_unreferenced_delegations(clp);
out:
dprintk("%s: done\n", __func__);
--
1.6.2.5