diff options
| author | Chuck Lever <chuck.lever@oracle.com> | 2014-05-28 10:34:57 -0400 |
|---|---|---|
| committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2014-06-04 08:56:52 -0400 |
| commit | e7ce710a8802351bd4118c5d6136c1d850f67cf9 (patch) | |
| tree | f9c4a23768955b85ee7d6cf519906004c86aff61 /net/sunrpc/xprtrdma/xprt_rdma.h | |
| parent | 4f4cf5ad6fc1b16dc8dc9d750bb80b35eba5e98d (diff) | |
xprtrdma: Avoid deadlock when credit window is reset
Update the cwnd while processing the server's reply. Otherwise the
next task on the xprt_sending queue is still subject to the old
credit window. Currently, no task is awoken if the old congestion
window is still exceeded, even if the new window is larger, and a
deadlock results.
This is an issue during a transport reconnect. Servers don't
normally shrink the credit window, but the client does reset it to
1 when reconnecting so the server can safely grow it again.
As a minor optimization, remove the hack of grabbing the initial
cwnd size (which happens to be RPC_CWNDSCALE) and using that value
as the congestion scaling factor. The scaling value is invariant,
and we are better off without the multiplication operation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'net/sunrpc/xprtrdma/xprt_rdma.h')
| -rw-r--r-- | net/sunrpc/xprtrdma/xprt_rdma.h | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h index 0c3b88ea5edb..89e7cd479705 100644 --- a/net/sunrpc/xprtrdma/xprt_rdma.h +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -212,7 +212,6 @@ struct rpcrdma_req { struct rpcrdma_buffer { spinlock_t rb_lock; /* protects indexes */ atomic_t rb_credits; /* most recent server credits */ - unsigned long rb_cwndscale; /* cached framework rpc_cwndscale */ int rb_max_requests;/* client max requests */ struct list_head rb_mws; /* optional memory windows/fmrs/frmrs */ int rb_send_index; |