xprtrdma: Basic support for Remote Invalidation

Have frwr's ro_unmap_sync recognize an invalidated rkey that appears
as part of a Receive completion. Local invalidation can be skipped
for that rkey.

Use an out-of-band signaling mechanism to indicate to the server
that the client is prepared to receive RDMA Send With Invalidate.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Chuck Lever 2016-09-15 10:57:16 -04:00 committed by Anna Schumaker
parent 87cfb9a0c8
commit c8b920bb49
6 changed files with 44 additions and 7 deletions

View File

@ -273,6 +273,7 @@ fmr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
*/
list_for_each_entry(mw, &req->rl_registered, mw_list)
list_add_tail(&mw->fmr.fm_mr->list, &unmap_list);
r_xprt->rx_stats.local_inv_needed++;
rc = ib_unmap_fmr(&unmap_list);
if (rc)
goto out_reset;
@ -330,4 +331,5 @@ const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = {
.ro_init_mr = fmr_op_init_mr,
.ro_release_mr = fmr_op_release_mr,
.ro_displayname = "fmr",
.ro_send_w_inv_ok = 0,
};

View File

@ -67,6 +67,8 @@
* pending send queue WRs before the transport is reconnected.
*/
#include <linux/sunrpc/rpc_rdma.h>
#include "xprt_rdma.h"
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
@ -471,6 +473,7 @@ static void
frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
{
struct ib_send_wr *invalidate_wrs, *pos, *prev, *bad_wr;
struct rpcrdma_rep *rep = req->rl_reply;
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
struct rpcrdma_mw *mw, *tmp;
struct rpcrdma_frmr *f;
@ -486,6 +489,12 @@ frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
f = NULL;
invalidate_wrs = pos = prev = NULL;
list_for_each_entry(mw, &req->rl_registered, mw_list) {
if ((rep->rr_wc_flags & IB_WC_WITH_INVALIDATE) &&
(mw->mw_handle == rep->rr_inv_rkey)) {
mw->frmr.fr_state = FRMR_IS_INVALID;
continue;
}
pos = __frwr_prepare_linv_wr(mw);
if (!invalidate_wrs)
@ -495,6 +504,8 @@ frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
prev = pos;
f = &mw->frmr;
}
if (!f)
goto unmap;
/* Strong send queue ordering guarantees that when the
* last WR in the chain completes, all WRs in the chain
@ -509,6 +520,7 @@ frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)
* replaces the QP. The RPC reply handler won't call us
* unless ri_id->qp is a valid pointer.
*/
r_xprt->rx_stats.local_inv_needed++;
rc = ib_post_send(ia->ri_id->qp, invalidate_wrs, &bad_wr);
if (rc)
goto reset_mrs;
@ -575,4 +587,5 @@ const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops = {
.ro_init_mr = frwr_op_init_mr,
.ro_release_mr = frwr_op_release_mr,
.ro_displayname = "frwr",
.ro_send_w_inv_ok = RPCRDMA_CMP_F_SND_W_INV_OK,
};

View File

@ -231,7 +231,8 @@ rpcrdma_convert_kvec(struct kvec *vec, struct rpcrdma_mr_seg *seg, int n)
static int
rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos,
enum rpcrdma_chunktype type, struct rpcrdma_mr_seg *seg)
enum rpcrdma_chunktype type, struct rpcrdma_mr_seg *seg,
bool reminv_expected)
{
int len, n, p, page_base;
struct page **ppages;
@ -273,6 +274,13 @@ rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos,
if (type == rpcrdma_readch)
return n;
/* When encoding the Write list, some servers need to see an extra
* segment for odd-length Write chunks. The upper layer provides
* space in the tail iovec for this purpose.
*/
if (type == rpcrdma_writech && reminv_expected)
return n;
if (xdrbuf->tail[0].iov_len) {
/* the rpcrdma protocol allows us to omit any trailing
* xdr pad bytes, saving the server an RDMA operation. */
@ -329,7 +337,7 @@ rpcrdma_encode_read_list(struct rpcrdma_xprt *r_xprt,
if (rtype == rpcrdma_areadch)
pos = 0;
seg = req->rl_segments;
nsegs = rpcrdma_convert_iovs(&rqst->rq_snd_buf, pos, rtype, seg);
nsegs = rpcrdma_convert_iovs(&rqst->rq_snd_buf, pos, rtype, seg, false);
if (nsegs < 0)
return ERR_PTR(nsegs);
@ -393,7 +401,8 @@ rpcrdma_encode_write_list(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,
seg = req->rl_segments;
nsegs = rpcrdma_convert_iovs(&rqst->rq_rcv_buf,
rqst->rq_rcv_buf.head[0].iov_len,
wtype, seg);
wtype, seg,
r_xprt->rx_ia.ri_reminv_expected);
if (nsegs < 0)
return ERR_PTR(nsegs);
@ -458,7 +467,8 @@ rpcrdma_encode_reply_chunk(struct rpcrdma_xprt *r_xprt,
}
seg = req->rl_segments;
nsegs = rpcrdma_convert_iovs(&rqst->rq_rcv_buf, 0, wtype, seg);
nsegs = rpcrdma_convert_iovs(&rqst->rq_rcv_buf, 0, wtype, seg,
r_xprt->rx_ia.ri_reminv_expected);
if (nsegs < 0)
return ERR_PTR(nsegs);

View File

@ -730,10 +730,11 @@ void xprt_rdma_print_stats(struct rpc_xprt *xprt, struct seq_file *seq)
r_xprt->rx_stats.failed_marshal_count,
r_xprt->rx_stats.bad_reply_count,
r_xprt->rx_stats.nomsg_call_count);
seq_printf(seq, "%lu %lu %lu\n",
seq_printf(seq, "%lu %lu %lu %lu\n",
r_xprt->rx_stats.mrs_recovered,
r_xprt->rx_stats.mrs_orphaned,
r_xprt->rx_stats.mrs_allocated);
r_xprt->rx_stats.mrs_allocated,
r_xprt->rx_stats.local_inv_needed);
}
static int

View File

@ -185,6 +185,9 @@ rpcrdma_receive_wc(struct ib_cq *cq, struct ib_wc *wc)
__func__, rep, wc->byte_len);
rep->rr_len = wc->byte_len;
rep->rr_wc_flags = wc->wc_flags;
rep->rr_inv_rkey = wc->ex.invalidate_rkey;
ib_dma_sync_single_for_cpu(rep->rr_device,
rdmab_addr(rep->rr_rdmabuf),
rep->rr_len, DMA_FROM_DEVICE);
@ -212,12 +215,15 @@ rpcrdma_update_connect_private(struct rpcrdma_xprt *r_xprt,
const struct rpcrdma_connect_private *pmsg = param->private_data;
unsigned int rsize, wsize;
/* Default settings for RPC-over-RDMA Version One */
r_xprt->rx_ia.ri_reminv_expected = false;
rsize = RPCRDMA_V1_DEF_INLINE_SIZE;
wsize = RPCRDMA_V1_DEF_INLINE_SIZE;
if (pmsg &&
pmsg->cp_magic == rpcrdma_cmp_magic &&
pmsg->cp_version == RPCRDMA_CMP_VERSION) {
r_xprt->rx_ia.ri_reminv_expected = true;
rsize = rpcrdma_decode_buffer_size(pmsg->cp_send_size);
wsize = rpcrdma_decode_buffer_size(pmsg->cp_recv_size);
}
@ -568,7 +574,7 @@ rpcrdma_ep_create(struct rpcrdma_ep *ep, struct rpcrdma_ia *ia,
/* Prepare RDMA-CM private message */
pmsg->cp_magic = rpcrdma_cmp_magic;
pmsg->cp_version = RPCRDMA_CMP_VERSION;
pmsg->cp_flags = 0;
pmsg->cp_flags |= ia->ri_ops->ro_send_w_inv_ok;
pmsg->cp_send_size = rpcrdma_encode_buffer_size(cdata->inline_wsize);
pmsg->cp_recv_size = rpcrdma_encode_buffer_size(cdata->inline_rsize);
ep->rep_remote_cma.private_data = pmsg;

View File

@ -74,6 +74,7 @@ struct rpcrdma_ia {
unsigned int ri_max_frmr_depth;
unsigned int ri_max_inline_write;
unsigned int ri_max_inline_read;
bool ri_reminv_expected;
struct ib_qp_attr ri_qp_attr;
struct ib_qp_init_attr ri_qp_init_attr;
};
@ -187,6 +188,8 @@ enum {
struct rpcrdma_rep {
struct ib_cqe rr_cqe;
unsigned int rr_len;
int rr_wc_flags;
u32 rr_inv_rkey;
struct ib_device *rr_device;
struct rpcrdma_xprt *rr_rxprt;
struct work_struct rr_work;
@ -385,6 +388,7 @@ struct rpcrdma_stats {
unsigned long mrs_recovered;
unsigned long mrs_orphaned;
unsigned long mrs_allocated;
unsigned long local_inv_needed;
};
/*
@ -408,6 +412,7 @@ struct rpcrdma_memreg_ops {
struct rpcrdma_mw *);
void (*ro_release_mr)(struct rpcrdma_mw *);
const char *ro_displayname;
const int ro_send_w_inv_ok;
};
extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops;