]> www.infradead.org Git - users/jedix/linux-maple.git/commit
xprtrdma: Don't provide a reply chunk when expecting a short reply
authorChuck Lever <chuck.lever@oracle.com>
Sat, 18 Oct 2014 13:45:57 +0000 (09:45 -0400)
committerChuck Lever <chuck.lever@oracle.com>
Mon, 31 Aug 2015 20:45:59 +0000 (14:45 -0600)
commit39e8baed87fc938b7986b34afb3d838cdd0c57ab
tree9929835386d99ef12469db684e690558ed807b54
parentf1b48414276ab7b18aaa4e322ef0ee59dc909047
xprtrdma: Don't provide a reply chunk when expecting a short reply

[ Queued for upstream v4.3 ]

Currently Linux always offers a reply chunk, even when the reply
can be sent inline (ie. is smaller than 1KB).

On the client, registering a memory region can be expensive. A
server may choose not to use the reply chunk, wasting the cost of
the registration.

This is a change only for RPC replies smaller than 1KB which the
server constructs in the RPC reply send buffer. Because the elements
of the reply must be XDR encoded, a copy-free data transfer has no
benefit in this case.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Tested-by: Devesh Sharma <devesh.sharma@avagotech.com>
net/sunrpc/xprtrdma/rpc_rdma.c