Commit 9d6b0409 authored by Chuck Lever's avatar Chuck Lever Committed by Anna Schumaker
Browse files

xprtrdma: Place registered MWs on a per-req list 



Instead of placing registered MWs sparsely into the rl_segments
array, place these MWs on a per-req list.

ro_unmap_{sync,safe} can then simply pull those MWs off the list
instead of walking through the array.

This change significantly reduces the size of struct rpcrdma_req
by removing nsegs and rl_mw from every array element.

As an additional clean-up, chunk co-ordinates are returned in the
"*mw" output argument so they are no longer needed in every
array element.

Signed-off-by: default avatarChuck Lever <chuck.lever@oracle.com>
Tested-by: default avatarSteve Wise <swise@opengridcomputing.com>
Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
parent 2ffc871a

net/sunrpc/xprtrdma/fmr_ops.c

+21 −44
Original line number Diff line number Diff line
@@ -101,6 +101,10 @@ fmr_op_release_mr(struct rpcrdma_mw *r) 
	LIST_HEAD(unmap_list);

	int rc;



	/* Ensure MW is not on any rl_registered list */

	if (!list_empty(&r->mw_list))

		list_del(&r->mw_list);



	kfree(r->fmr.fm_physaddrs);

	kfree(r->mw_sg);
@@ -176,17 +180,13 @@ fmr_op_maxpages(struct rpcrdma_xprt *r_xprt) 
 */

static int

fmr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,

	   int nsegs, bool writing)

	   int nsegs, bool writing, struct rpcrdma_mw **out)

{

	struct rpcrdma_mr_seg *seg1 = seg;

	int len, pageoff, i, rc;

	struct rpcrdma_mw *mw;

	u64 *dma_pages;



	mw = seg1->rl_mw;

	seg1->rl_mw = NULL;

	if (mw)

		rpcrdma_defer_mr_recovery(mw);

	mw = rpcrdma_get_mw(r_xprt);

	if (!mw)

		return -ENOBUFS;
@@ -230,11 +230,11 @@ fmr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, 
	if (rc)

		goto out_maperr;



	seg1->rl_mw = mw;

	seg1->mr_rkey = mw->fmr.fm_mr->rkey;

	seg1->mr_base = dma_pages[0] + pageoff;

	seg1->mr_nsegs = mw->mw_nents;

	seg1->mr_len = len;

	mw->mw_handle = mw->fmr.fm_mr->rkey;

	mw->mw_length = len;

	mw->mw_offset = dma_pages[0] + pageoff;



	*out = mw;

	return mw->mw_nents;



out_dmamap_err:
@@ -255,13 +255,13 @@ out_maperr: 
 *

 * Sleeps until it is safe for the host CPU to access the

 * previously mapped memory regions.

 *

 * Caller ensures that req->rl_registered is not empty.

 */

static void

fmr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req)

{

	struct rpcrdma_mr_seg *seg;

	unsigned int i, nchunks;

	struct rpcrdma_mw *mw;

	struct rpcrdma_mw *mw, *tmp;

	LIST_HEAD(unmap_list);

	int rc;
@@ -272,14 +272,8 @@ fmr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req) 
	 * ib_unmap_fmr() is slow, so use a single call instead

	 * of one call per mapped FMR.

	 */

	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {

		seg = &req->rl_segments[i];

		mw = seg->rl_mw;



	list_for_each_entry(mw, &req->rl_registered, mw_list)

		list_add_tail(&mw->fmr.fm_mr->list, &unmap_list);



		i += seg->mr_nsegs;

	}

	rc = ib_unmap_fmr(&unmap_list);

	if (rc)

		goto out_reset;
@@ -287,34 +281,22 @@ fmr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req) 
	/* ORDER: Now DMA unmap all of the req's MRs, and return

	 * them to the free MW list.

	 */

	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {

		seg = &req->rl_segments[i];

		mw = seg->rl_mw;



	list_for_each_entry_safe(mw, tmp, &req->rl_registered, mw_list) {

		list_del_init(&mw->mw_list);

		list_del_init(&mw->fmr.fm_mr->list);

		ib_dma_unmap_sg(r_xprt->rx_ia.ri_device,

				mw->mw_sg, mw->mw_nents, mw->mw_dir);

		rpcrdma_put_mw(r_xprt, mw);



		i += seg->mr_nsegs;

		seg->mr_nsegs = 0;

		seg->rl_mw = NULL;

	}



	req->rl_nchunks = 0;

	return;



out_reset:

	pr_err("rpcrdma: ib_unmap_fmr failed (%i)\n", rc);



	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {

		seg = &req->rl_segments[i];

		mw = seg->rl_mw;



	list_for_each_entry_safe(mw, tmp, &req->rl_registered, mw_list) {

		list_del_init(&mw->fmr.fm_mr->list);

		fmr_op_recover_mr(mw);



		i += seg->mr_nsegs;

	}

}
@@ -325,22 +307,17 @@ static void 
fmr_op_unmap_safe(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,

		  bool sync)

{

	struct rpcrdma_mr_seg *seg;

	struct rpcrdma_mw *mw;

	unsigned int i;



	for (i = 0; req->rl_nchunks; req->rl_nchunks--) {

		seg = &req->rl_segments[i];

		mw = seg->rl_mw;

	while (!list_empty(&req->rl_registered)) {

		mw = list_first_entry(&req->rl_registered,

				      struct rpcrdma_mw, mw_list);

		list_del_init(&mw->mw_list);



		if (sync)

			fmr_op_recover_mr(mw);

		else

			rpcrdma_defer_mr_recovery(mw);



		i += seg->mr_nsegs;

		seg->mr_nsegs = 0;

		seg->rl_mw = NULL;

	}

}

net/sunrpc/xprtrdma/frwr_ops.c

+25 −47
Original line number Diff line number Diff line
@@ -128,6 +128,10 @@ frwr_op_release_mr(struct rpcrdma_mw *r) 
{

	int rc;



	/* Ensure MW is not on any rl_registered list */

	if (!list_empty(&r->mw_list))

		list_del(&r->mw_list);



	rc = ib_dereg_mr(r->frmr.fr_mr);

	if (rc)

		pr_err("rpcrdma: final ib_dereg_mr for %p returned %i\n",
@@ -333,10 +337,9 @@ frwr_wc_localinv_wake(struct ib_cq *cq, struct ib_wc *wc) 
 */

static int

frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,

	    int nsegs, bool writing)

	    int nsegs, bool writing, struct rpcrdma_mw **out)

{

	struct rpcrdma_ia *ia = &r_xprt->rx_ia;

	struct rpcrdma_mr_seg *seg1 = seg;

	struct rpcrdma_mw *mw;

	struct rpcrdma_frmr *frmr;

	struct ib_mr *mr;
@@ -345,8 +348,7 @@ frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, 
	int rc, i, n, dma_nents;

	u8 key;



	mw = seg1->rl_mw;

	seg1->rl_mw = NULL;

	mw = NULL;

	do {

		if (mw)

			rpcrdma_defer_mr_recovery(mw);
@@ -416,12 +418,11 @@ frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg, 
	if (rc)

		goto out_senderr;



	seg1->rl_mw = mw;

	seg1->mr_rkey = mr->rkey;

	seg1->mr_base = mr->iova;

	seg1->mr_nsegs = mw->mw_nents;

	seg1->mr_len = mr->length;

	mw->mw_handle = mr->rkey;

	mw->mw_length = mr->length;

	mw->mw_offset = mr->iova;



	*out = mw;

	return mw->mw_nents;



out_dmamap_err:
@@ -443,9 +444,8 @@ out_senderr: 
}



static struct ib_send_wr *

__frwr_prepare_linv_wr(struct rpcrdma_mr_seg *seg)

__frwr_prepare_linv_wr(struct rpcrdma_mw *mw)

{

	struct rpcrdma_mw *mw = seg->rl_mw;

	struct rpcrdma_frmr *f = &mw->frmr;

	struct ib_send_wr *invalidate_wr;
@@ -465,16 +465,16 @@ __frwr_prepare_linv_wr(struct rpcrdma_mr_seg *seg) 
 *

 * Sleeps until it is safe for the host CPU to access the

 * previously mapped memory regions.

 *

 * Caller ensures that req->rl_registered is not empty.

 */

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_ia *ia = &r_xprt->rx_ia;

	struct rpcrdma_mr_seg *seg;

	unsigned int i, nchunks;

	struct rpcrdma_mw *mw, *tmp;

	struct rpcrdma_frmr *f;

	struct rpcrdma_mw *mw;

	int rc;



	dprintk("RPC:       %s: req %p\n", __func__, req);
@@ -484,22 +484,18 @@ frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req) 
	 * Chain the LOCAL_INV Work Requests and post them with

	 * a single ib_post_send() call.

	 */

	f = NULL;

	invalidate_wrs = pos = prev = NULL;

	seg = NULL;

	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {

		seg = &req->rl_segments[i];



		pos = __frwr_prepare_linv_wr(seg);

	list_for_each_entry(mw, &req->rl_registered, mw_list) {

		pos = __frwr_prepare_linv_wr(mw);



		if (!invalidate_wrs)

			invalidate_wrs = pos;

		else

			prev->next = pos;

		prev = pos;



		i += seg->mr_nsegs;

		f = &mw->frmr;

	}

	f = &seg->rl_mw->frmr;



	/* Strong send queue ordering guarantees that when the

	 * last WR in the chain completes, all WRs in the chain
@@ -524,20 +520,12 @@ frwr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req) 
	 * them to the free MW list.

	 */

unmap:

	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {

		seg = &req->rl_segments[i];

		mw = seg->rl_mw;

		seg->rl_mw = NULL;



	list_for_each_entry_safe(mw, tmp, &req->rl_registered, mw_list) {

		list_del_init(&mw->mw_list);

		ib_dma_unmap_sg(ia->ri_device,

				mw->mw_sg, mw->mw_nents, mw->mw_dir);

		rpcrdma_put_mw(r_xprt, mw);



		i += seg->mr_nsegs;

		seg->mr_nsegs = 0;

	}



	req->rl_nchunks = 0;

	return;



reset_mrs:
@@ -547,17 +535,12 @@ reset_mrs: 
	/* Find and reset the MRs in the LOCAL_INV WRs that did not

	 * get posted. This is synchronous, and slow.

	 */

	for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) {

		seg = &req->rl_segments[i];

		mw = seg->rl_mw;

	list_for_each_entry(mw, &req->rl_registered, mw_list) {

		f = &mw->frmr;



		if (mw->frmr.fr_mr->rkey == bad_wr->ex.invalidate_rkey) {

			__frwr_reset_mr(ia, mw);

			bad_wr = bad_wr->next;

		}



		i += seg->mr_nsegs;

	}

	goto unmap;

}
@@ -569,22 +552,17 @@ static void 
frwr_op_unmap_safe(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req,

		   bool sync)

{

	struct rpcrdma_mr_seg *seg;

	struct rpcrdma_mw *mw;

	unsigned int i;



	for (i = 0; req->rl_nchunks; req->rl_nchunks--) {

		seg = &req->rl_segments[i];

		mw = seg->rl_mw;

	while (!list_empty(&req->rl_registered)) {

		mw = list_first_entry(&req->rl_registered,

				      struct rpcrdma_mw, mw_list);

		list_del_init(&mw->mw_list);



		if (sync)

			frwr_op_recover_mr(mw);

		else

			rpcrdma_defer_mr_recovery(mw);



		i += seg->mr_nsegs;

		seg->mr_nsegs = 0;

		seg->rl_mw = NULL;

	}

}

net/sunrpc/xprtrdma/rpc_rdma.c

+38 −43
Original line number Diff line number Diff line
@@ -286,11 +286,11 @@ rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos, 
}



static inline __be32 *

xdr_encode_rdma_segment(__be32 *iptr, struct rpcrdma_mr_seg *seg)

xdr_encode_rdma_segment(__be32 *iptr, struct rpcrdma_mw *mw)

{

	*iptr++ = cpu_to_be32(seg->mr_rkey);

	*iptr++ = cpu_to_be32(seg->mr_len);

	return xdr_encode_hyper(iptr, seg->mr_base);

	*iptr++ = cpu_to_be32(mw->mw_handle);

	*iptr++ = cpu_to_be32(mw->mw_length);

	return xdr_encode_hyper(iptr, mw->mw_offset);

}



/* XDR-encode the Read list. Supports encoding a list of read
@@ -311,6 +311,7 @@ rpcrdma_encode_read_list(struct rpcrdma_xprt *r_xprt, 
			 __be32 *iptr, enum rpcrdma_chunktype rtype)

{

	struct rpcrdma_mr_seg *seg = req->rl_nextseg;

	struct rpcrdma_mw *mw;

	unsigned int pos;

	int n, nsegs;
@@ -328,9 +329,11 @@ rpcrdma_encode_read_list(struct rpcrdma_xprt *r_xprt, 
		return ERR_PTR(nsegs);



	do {

		n = r_xprt->rx_ia.ri_ops->ro_map(r_xprt, seg, nsegs, false);

		n = r_xprt->rx_ia.ri_ops->ro_map(r_xprt, seg, nsegs,

						 false, &mw);

		if (n < 0)

			return ERR_PTR(n);

		list_add(&mw->mw_list, &req->rl_registered);



		*iptr++ = xdr_one;	/* item present */
@@ -338,13 +341,12 @@ rpcrdma_encode_read_list(struct rpcrdma_xprt *r_xprt, 
		 * have the same "position".

		 */

		*iptr++ = cpu_to_be32(pos);

		iptr = xdr_encode_rdma_segment(iptr, seg);

		iptr = xdr_encode_rdma_segment(iptr, mw);



		dprintk("RPC: %5u %s: read segment pos %u "

			"%d@0x%016llx:0x%08x (%s)\n",

		dprintk("RPC: %5u %s: pos %u %u@0x%016llx:0x%08x (%s)\n",

			rqst->rq_task->tk_pid, __func__, pos,

			seg->mr_len, (unsigned long long)seg->mr_base,

			seg->mr_rkey, n < nsegs ? "more" : "last");

			mw->mw_length, (unsigned long long)mw->mw_offset,

			mw->mw_handle, n < nsegs ? "more" : "last");



		r_xprt->rx_stats.read_chunk_count++;

		req->rl_nchunks++;
@@ -376,6 +378,7 @@ rpcrdma_encode_write_list(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req, 
			  enum rpcrdma_chunktype wtype)

{

	struct rpcrdma_mr_seg *seg = req->rl_nextseg;

	struct rpcrdma_mw *mw;

	int n, nsegs, nchunks;

	__be32 *segcount;
@@ -396,17 +399,18 @@ rpcrdma_encode_write_list(struct rpcrdma_xprt *r_xprt, struct rpcrdma_req *req, 


	nchunks = 0;

	do {

		n = r_xprt->rx_ia.ri_ops->ro_map(r_xprt, seg, nsegs, true);

		n = r_xprt->rx_ia.ri_ops->ro_map(r_xprt, seg, nsegs,

						 true, &mw);

		if (n < 0)

			return ERR_PTR(n);

		list_add(&mw->mw_list, &req->rl_registered);



		iptr = xdr_encode_rdma_segment(iptr, seg);

		iptr = xdr_encode_rdma_segment(iptr, mw);



		dprintk("RPC: %5u %s: write segment "

			"%d@0x016%llx:0x%08x (%s)\n",

		dprintk("RPC: %5u %s: %u@0x016%llx:0x%08x (%s)\n",

			rqst->rq_task->tk_pid, __func__,

			seg->mr_len, (unsigned long long)seg->mr_base,

			seg->mr_rkey, n < nsegs ? "more" : "last");

			mw->mw_length, (unsigned long long)mw->mw_offset,

			mw->mw_handle, n < nsegs ? "more" : "last");



		r_xprt->rx_stats.write_chunk_count++;

		r_xprt->rx_stats.total_rdma_request += seg->mr_len;
@@ -443,6 +447,7 @@ rpcrdma_encode_reply_chunk(struct rpcrdma_xprt *r_xprt, 
			   __be32 *iptr, enum rpcrdma_chunktype wtype)

{

	struct rpcrdma_mr_seg *seg = req->rl_nextseg;

	struct rpcrdma_mw *mw;

	int n, nsegs, nchunks;

	__be32 *segcount;
@@ -461,17 +466,18 @@ rpcrdma_encode_reply_chunk(struct rpcrdma_xprt *r_xprt, 


	nchunks = 0;

	do {

		n = r_xprt->rx_ia.ri_ops->ro_map(r_xprt, seg, nsegs, true);

		n = r_xprt->rx_ia.ri_ops->ro_map(r_xprt, seg, nsegs,

						 true, &mw);

		if (n < 0)

			return ERR_PTR(n);

		list_add(&mw->mw_list, &req->rl_registered);



		iptr = xdr_encode_rdma_segment(iptr, seg);

		iptr = xdr_encode_rdma_segment(iptr, mw);



		dprintk("RPC: %5u %s: reply segment "

			"%d@0x%016llx:0x%08x (%s)\n",

		dprintk("RPC: %5u %s: %u@0x%016llx:0x%08x (%s)\n",

			rqst->rq_task->tk_pid, __func__,

			seg->mr_len, (unsigned long long)seg->mr_base,

			seg->mr_rkey, n < nsegs ? "more" : "last");

			mw->mw_length, (unsigned long long)mw->mw_offset,

			mw->mw_handle, n < nsegs ? "more" : "last");



		r_xprt->rx_stats.reply_chunk_count++;

		r_xprt->rx_stats.total_rdma_request += seg->mr_len;
@@ -690,10 +696,7 @@ rpcrdma_marshal_req(struct rpc_rqst *rqst) 
out_overflow:

	pr_err("rpcrdma: send overflow: hdrlen %zd rpclen %zu %s/%s\n",

		hdrlen, rpclen, transfertypes[rtype], transfertypes[wtype]);

	/* Terminate this RPC. Chunks registered above will be

	 * released by xprt_release -> xprt_rmda_free .

	 */

	return -EIO;

	iptr = ERR_PTR(-EIO);



out_unmap:

	r_xprt->rx_ia.ri_ops->ro_unmap_safe(r_xprt, req, false);
@@ -705,15 +708,13 @@ out_unmap: 
 * RDMA'd by server. See map at rpcrdma_create_chunks()! :-)

 */

static int

rpcrdma_count_chunks(struct rpcrdma_rep *rep, unsigned int max, int wrchunk, __be32 **iptrp)

rpcrdma_count_chunks(struct rpcrdma_rep *rep, int wrchunk, __be32 **iptrp)

{

	unsigned int i, total_len;

	struct rpcrdma_write_chunk *cur_wchunk;

	char *base = (char *)rdmab_to_msg(rep->rr_rdmabuf);



	i = be32_to_cpu(**iptrp);

	if (i > max)

		return -1;

	cur_wchunk = (struct rpcrdma_write_chunk *) (*iptrp + 1);

	total_len = 0;

	while (i--) {
@@ -960,14 +961,13 @@ rpcrdma_reply_handler(struct rpcrdma_rep *rep) 
		    (headerp->rm_body.rm_chunks[1] == xdr_zero &&

		     headerp->rm_body.rm_chunks[2] != xdr_zero) ||

		    (headerp->rm_body.rm_chunks[1] != xdr_zero &&

		     req->rl_nchunks == 0))

		     list_empty(&req->rl_registered)))

			goto badheader;

		if (headerp->rm_body.rm_chunks[1] != xdr_zero) {

			/* count any expected write chunks in read reply */

			/* start at write chunk array count */

			iptr = &headerp->rm_body.rm_chunks[2];

			rdmalen = rpcrdma_count_chunks(rep,

						req->rl_nchunks, 1, &iptr);

			rdmalen = rpcrdma_count_chunks(rep, 1, &iptr);

			/* check for validity, and no reply chunk after */

			if (rdmalen < 0 || *iptr++ != xdr_zero)

				goto badheader;
@@ -997,11 +997,11 @@ rpcrdma_reply_handler(struct rpcrdma_rep *rep) 
		if (headerp->rm_body.rm_chunks[0] != xdr_zero ||

		    headerp->rm_body.rm_chunks[1] != xdr_zero ||

		    headerp->rm_body.rm_chunks[2] != xdr_one ||

		    req->rl_nchunks == 0)

		    list_empty(&req->rl_registered))

			goto badheader;

		iptr = (__be32 *)((unsigned char *)headerp +

							RPCRDMA_HDRLEN_MIN);

		rdmalen = rpcrdma_count_chunks(rep, req->rl_nchunks, 0, &iptr);

		rdmalen = rpcrdma_count_chunks(rep, 0, &iptr);

		if (rdmalen < 0)

			goto badheader;

		r_xprt->rx_stats.total_rdma_reply += rdmalen;
@@ -1014,14 +1014,9 @@ rpcrdma_reply_handler(struct rpcrdma_rep *rep) 


badheader:

	default:

		dprintk("%s: invalid rpcrdma reply header (type %d):"

				" chunks[012] == %d %d %d"

				" expected chunks <= %d\n",

				__func__, be32_to_cpu(headerp->rm_type),

				headerp->rm_body.rm_chunks[0],

				headerp->rm_body.rm_chunks[1],

				headerp->rm_body.rm_chunks[2],

				req->rl_nchunks);

		dprintk("RPC: %5u %s: invalid rpcrdma reply (type %u)\n",

			rqst->rq_task->tk_pid, __func__,

			be32_to_cpu(headerp->rm_type));

		status = -EIO;

		r_xprt->rx_stats.bad_reply_count++;

		break;
@@ -1035,7 +1030,7 @@ out: 
	 * control: waking the next RPC waits until this RPC has

	 * relinquished all its Send Queue entries.

	 */

	if (req->rl_nchunks)

	if (!list_empty(&req->rl_registered))

		r_xprt->rx_ia.ri_ops->ro_unmap_sync(r_xprt, req);



	spin_lock_bh(&xprt->transport_lock);

net/sunrpc/xprtrdma/transport.c

+3 −0
Original line number Diff line number Diff line
@@ -619,6 +619,9 @@ xprt_rdma_send_request(struct rpc_task *task) 
	struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);

	int rc = 0;



	/* On retransmit, remove any previously registered chunks */

	r_xprt->rx_ia.ri_ops->ro_unmap_safe(r_xprt, req, false);



	rc = rpcrdma_marshal_req(rqst);

	if (rc < 0)

		goto failed_marshal;

net/sunrpc/xprtrdma/verbs.c

+1 −0
Original line number Diff line number Diff line
@@ -847,6 +847,7 @@ rpcrdma_create_req(struct rpcrdma_xprt *r_xprt) 
	spin_unlock(&buffer->rb_reqslock);

	req->rl_cqe.done = rpcrdma_wc_send;

	req->rl_buffer = &r_xprt->rx_buf;

	INIT_LIST_HEAD(&req->rl_registered);

	return req;

}

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