redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

xprtrdma: Pre-allocate Work Requests for backchannel

Browse source 
Pre-allocate extra send and receive Work Requests needed to handle
backchannel receives and sends.

The transport doesn't know how many extra WRs to pre-allocate until
the xprt_setup_backchannel() call, but that's long after the WRs are
allocated during forechannel setup.

So, use a fixed value for now.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Tested-By: Devesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Chuck Lever 2015-10-24 17:27:51 -04:00 committed by Anna Schumaker
parent f531a5dbc4
commit 124fa17d3e
3 changed files with 26 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
net/sunrpc/xprtrdma/backchannel.c
View file

@ -125,6 +125,9 @@ int xprt_rdma_bc_setup(struct rpc_xprt *xprt, unsigned int reqs)
* Twice as many rpc_rqsts are prepared to ensure there is
* always an rpc_rqst available as soon as a reply is sent.
*/
if (reqs > RPCRDMA_BACKWARD_WRS >> 1)
goto out_err;
for (i = 0; i < (reqs << 1); i++) {
rqst = kzalloc(sizeof(*rqst), GFP_KERNEL);
if (!rqst) {
@ -161,6 +164,7 @@ int xprt_rdma_bc_setup(struct rpc_xprt *xprt, unsigned int reqs)
out_free:
xprt_rdma_bc_destroy(xprt, reqs);
out_err:
pr_err("RPC: %s: setup backchannel transport failed\n", __func__);
return -ENOMEM;
}

14
net/sunrpc/xprtrdma/verbs.c
View file

@ -568,6 +568,7 @@ rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
struct ib_device_attr *devattr = &ia->ri_devattr;
struct ib_cq *sendcq, *recvcq;
struct ib_cq_init_attr cq_attr = {};
unsigned int max_qp_wr;
int rc, err;
if (devattr->max_sge < RPCRDMA_MAX_IOVS) {
@ -576,18 +577,27 @@ rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
return -ENOMEM;
}
if (devattr->max_qp_wr <= RPCRDMA_BACKWARD_WRS) {
dprintk("RPC: %s: insufficient wqe's available\n",
__func__);
return -ENOMEM;
}
max_qp_wr = devattr->max_qp_wr - RPCRDMA_BACKWARD_WRS;
/* check provider's send/recv wr limits */
if (cdata->max_requests > devattr->max_qp_wr)
cdata->max_requests = devattr->max_qp_wr;
if (cdata->max_requests > max_qp_wr)
cdata->max_requests = max_qp_wr;
ep->rep_attr.event_handler = rpcrdma_qp_async_error_upcall;
ep->rep_attr.qp_context = ep;
ep->rep_attr.srq = NULL;
ep->rep_attr.cap.max_send_wr = cdata->max_requests;
ep->rep_attr.cap.max_send_wr += RPCRDMA_BACKWARD_WRS;
rc = ia->ri_ops->ro_open(ia, ep, cdata);
if (rc)
return rc;
ep->rep_attr.cap.max_recv_wr = cdata->max_requests;
ep->rep_attr.cap.max_recv_wr += RPCRDMA_BACKWARD_WRS;
ep->rep_attr.cap.max_send_sge = RPCRDMA_MAX_IOVS;
ep->rep_attr.cap.max_recv_sge = 1;
ep->rep_attr.cap.max_inline_data = 0;

10
net/sunrpc/xprtrdma/xprt_rdma.h
View file

@ -101,6 +101,16 @@ struct rpcrdma_ep {
*/
#define RPCRDMA_IGNORE_COMPLETION (0ULL)
/* Pre-allocate extra Work Requests for handling backward receives
* and sends. This is a fixed value because the Work Queues are
* allocated when the forward channel is set up.
*/
#if defined(CONFIG_SUNRPC_BACKCHANNEL)
#define RPCRDMA_BACKWARD_WRS (8)
#else
#define RPCRDMA_BACKWARD_WRS (0)
#endif
/* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV
*
* The below structure appears at the front of a large region of kmalloc'd