SQUASHME: Support for cb_layout returning NFS4ERR_DELAY
Subsystems (2)
PATCH 1/1 SQUASHME: Support for cb_layout returning NFS4ERR_DELAY
On a recall, a client may return NFS4ERR_DELAY to indicate that it is busy with the layout and wants to be poled.
TODO: If the client is stuck he would probably be cleaned
at expire client. But it is possible that the client is active/renewing but would not acknowledge the recall. We should take a time stamp on first recall and expire the client if a lease time has passed.
--- fs/nfsd/nfs4callback.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-)
fs/nfsd/nfs4callback.c +6 -0
@@ -1044,6 +1044,12 @@ static void nfsd4_cb_layout_done(struct rpc_task *task, void *calldata)*/ expire_client_lock (clp);break ; +case -NFS4ERR_DELAY : +/* Pole the client until it's done with the layout */ +rpc_delay (task,HZ /100 );/* 10 mili-seconds */ + task->tk_status =0 ; +rpc_restart_call (task); +break ;case -NFS4ERR_NOMATCHING_LAYOUT :nomatching_layout (clr); }
Signature · 1 line
1.7.0.1
Merged at pnfs-all-2.6.35-rc3-2010-06-17-1
Thanks!
Benny
Quoted 32 lines · Boaz Harrosh
On a recall, a client may return
NFS4ERR_DELAYto indicate that it is busy with the layout and wants to be poled.TODO: If the client is stuck he would probably be cleaned
at expire client. But it is possible that the client is active/renewing but would not acknowledge the recall. We should take a time stamp on first recall and expire the client if a lease time has passed.Signed-off-by Boaz Harrosh <[email protected]>--- fs/nfsd/nfs4callback.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-)fs/nfsd/nfs4callback.c +6
-0@@ -1044,6 +1044,12 @@ static void nfsd4_cb_layout_done(struct rpc_task *task, void *calldata)*/ expire_client_lock (clp);break ; +case -NFS4ERR_DELAY : +/* Pole the client until it's done with the layout */ +rpc_delay (task,HZ /100 );/* 10 mili-seconds */ + task->tk_status =0 ; +rpc_restart_call (task); +break ;case -NFS4ERR_NOMATCHING_LAYOUT :nomatching_layout (clr); }
Quoted 11 lines · Boaz Harrosh
On a recall, a client may return
NFS4ERR_DELAYto indicate that it is busy with the layout and wants to be poled.TODO: If the client is stuck he would probably be cleaned
at expire client. But it is possible that the client is active/renewing but would not acknowledge the recall. We should take a time stamp on first recall and expire the client if a lease time has passed.Signed-off-by Boaz Harrosh <[email protected]>
So I was still crashing on callbacks all during bakethon even with this patch and Benny's fixes. (See below)
Quoted 9 lines
--- fs/nfsd/nfs4callback.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-)fs/nfsd/nfs4callback.c +0
-0
fs/nfsd/nfs4callback.c static void nfsd4_cb_layout_done(struct rpc_task *task, void *calldata) · line 1051
Quoted 8 lines
fs/nfsd/nfs4callback.c +5
-0@@ -1044,6 +1044,12 @@ static void nfsd4_cb_layout_done(struct rpc_task *task, void *calldata)*/ expire_client_lock (clp);break ; +case -NFS4ERR_DELAY : +/* Pole the client until it's done with the layout */ +rpc_delay (task,HZ /100 );/* 10 mili-seconds */ + task->tk_status =0 ; +rpc_restart_call (task);
When using rpc_restart_call here I get an hard crash at:
fs/nfsd/nfs4callback.c +1 -0
@@ -514,6 +514,7 @@ decode_cb_sequence(struct xdr_stream *xdr, struct nfsd4_cb_sequence *res,u32 dummy;__be32 *p; +BUG_ON (!res);if (res->cbs_minorversion ==0 )return 0 ;
[BUG_ON added for demonstration]
The below code would fix it. (Obviously)
fs/nfsd/nfs4callback.c +0 -3
@@ -869,9 +870,6 @@ static void nfsd4_cb_done_sequence(struct rpc_task *task,rpc_wake_up_next (&clp->cl_cb_waitq);dprintk ("%s: freed slot, new seqid=%d\n" , __func__, clp->cl_cb_seq_nr); - -/* We're done looking into the sequence information */ - task->tk_msg.rpc_resp =NULL ; } }
This is because when the second rpc, that was retried above in nfsd4_cb_layout_done() has a NULL ->rpc_resp. (Which is the struct nfsd4_cb_sequence *res parameter to decode_cb_sequence on reply from server).
Now this above nfsd4_cb_layout_done() is new pNFS code, but the same problem (crash) should apply when a retry is attempted in nfsd4_cb_recall_done(). So this hunk should go into current tree. (and stable)
The code was introduced by this patch:
0421b5c55acd0e88920cb9a5bcea6ed738186853
From: Ricardo Labiaga <[email protected]>
Subject: [PATCH] nfsd41: Backchannel: Implement cb_recall over NFSv4.1
I guess it was never tested with error on callback and retry attempt. Ricardo what was the original intention of the line above (plus the comment)
[I'll send an official patch to Bruce as well]
Thanks
Boaz
Quoted 4 lines
fs/nfsd/nfs4callback.c +1
-0+break ;case -NFS4ERR_NOMATCHING_LAYOUT :nomatching_layout (clr); }
PATCH 1/1 SQUASHME: into [SQUASHME: pnfsd: Support for cb_layout returning NFS4ERR_DELAY]
This is the correct code.
--- fs/nfsd/nfs4callback.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)
fs/nfsd/nfs4callback.c +1 -1
@@ -1046,7 +1046,7 @@ static void nfsd4_cb_layout_done(struct rpc_task *task, void *calldata)/* Pole the client until it's done with the layout */ rpc_delay (task,HZ /100 );/* 10 mili-seconds */ task->tk_status =0 ; -rpc_restart_call (task); +rpc_restart_call_prepare (task);break ;case -NFS4ERR_NOMATCHING_LAYOUT : task->tk_status =0 ;
Signature · 1 line
1.6.6.1
Re: [PATCH] SQUASHME: into [SQUASHME: pnfsd: Support for cb_layout returning NFS4ERR_DELAY]
Quoted 4 lines · Boaz Harrosh
This is the correct code.
Signed-off-by Boaz Harrosh <[email protected]>
Merged at pnfs-all-2.6.35-rc3-2010-07-01
Thanks!
Benny
Quoted 17 lines
--- fs/nfsd/nfs4callback.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)fs/nfsd/nfs4callback.c +1
-1@@ -1046,7 +1046,7 @@ static void nfsd4_cb_layout_done(struct rpc_task *task, void *calldata)/* Pole the client until it's done with the layout */ rpc_delay (task,HZ /100 );/* 10 mili-seconds */ task->tk_status =0 ; -rpc_restart_call (task); +rpc_restart_call_prepare (task);break ;case -NFS4ERR_NOMATCHING_LAYOUT : task->tk_status =0 ;