On Mon, Oct 8, 2012 at 1:50 PM, Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> wrote: > Aside from it being a layering violation, there is no point in doing so: > - If slots are available, then the waitqueue will be empty. > - If no slots are available, then the wake up just causes waitqueue churn We call rpc_wake_up so that I/O waiting on the DS session, all of which needs to be re-directed to the MDS (not via the state recovery machinery), will by-pass the RPC machine "try each task one at a time and redirect on failure" which includes the 60 second TCP timeout on DS connection failures. So, it doesn't just cause waitqueue churn, it significantly reduces the time it takes to recover to the MDS. -->Andy > - If the slot table is being drained, then the state recovery machinery > will manage the waitqueue using the calls to nfs4_begin/end_drain_session. > > Signed-off-by: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> > --- > fs/nfs/nfs4filelayout.c | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c > index 52d8472..368f11f 100644 > --- a/fs/nfs/nfs4filelayout.c > +++ b/fs/nfs/nfs4filelayout.c > @@ -131,7 +131,6 @@ static int filelayout_async_handle_error(struct rpc_task *task, > struct nfs_server *mds_server = NFS_SERVER(inode); > struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg); > struct nfs_client *mds_client = mds_server->nfs_client; > - struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table; > > if (task->tk_status >= 0) > return 0; > @@ -191,7 +190,6 @@ static int filelayout_async_handle_error(struct rpc_task *task, > * layout is destroyed and a new valid layout is obtained. > */ > pnfs_destroy_layout(NFS_I(inode)); > - rpc_wake_up(&tbl->slot_tbl_waitq); > goto reset; > /* RPC connection errors */ > case -ECONNREFUSED: > @@ -206,7 +204,6 @@ static int filelayout_async_handle_error(struct rpc_task *task, > nfs4_mark_deviceid_unavailable(devid); > clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(inode)->flags); > _pnfs_return_layout(inode); > - rpc_wake_up(&tbl->slot_tbl_waitq); > nfs4_ds_disconnect(clp); > /* fall through */ > default: > -- > 1.7.11.4 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
