svcrdma: Modify the RPC reply path to use FRMR when available
Use FRMR to map local RPC reply data. This allows RDMA_WRITE to send reply data using a single WR. The FRMR is invalidated by linking the LOCAL_INV WR to the RDMA_SEND message used to complete the reply. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
This commit is contained in:
Tom Tucker
Родитель
146b6df6a5
Коммит
afd566ea08
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@ -69,9 +69,127 @@
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* array is only concerned with the reply we are assured that we have
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* on extra page for the RPCRMDA header.
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*/
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static void xdr_to_sge(struct svcxprt_rdma *xprt,
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struct xdr_buf *xdr,
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struct svc_rdma_req_map *vec)
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int fast_reg_xdr(struct svcxprt_rdma *xprt,
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struct xdr_buf *xdr,
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struct svc_rdma_req_map *vec)
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{
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int sge_no;
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u32 sge_bytes;
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u32 page_bytes;
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u32 page_off;
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int page_no = 0;
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u8 *frva;
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struct svc_rdma_fastreg_mr *frmr;
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frmr = svc_rdma_get_frmr(xprt);
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if (IS_ERR(frmr))
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return -ENOMEM;
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vec->frmr = frmr;
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/* Skip the RPCRDMA header */
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sge_no = 1;
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/* Map the head. */
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frva = (void *)((unsigned long)(xdr->head[0].iov_base) & PAGE_MASK);
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vec->sge[sge_no].iov_base = xdr->head[0].iov_base;
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vec->sge[sge_no].iov_len = xdr->head[0].iov_len;
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vec->count = 2;
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sge_no++;
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/* Build the FRMR */
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frmr->kva = frva;
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frmr->direction = DMA_TO_DEVICE;
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frmr->access_flags = 0;
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frmr->map_len = PAGE_SIZE;
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frmr->page_list_len = 1;
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frmr->page_list->page_list[page_no] =
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ib_dma_map_single(xprt->sc_cm_id->device,
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(void *)xdr->head[0].iov_base,
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PAGE_SIZE, DMA_TO_DEVICE);
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if (ib_dma_mapping_error(xprt->sc_cm_id->device,
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frmr->page_list->page_list[page_no]))
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goto fatal_err;
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atomic_inc(&xprt->sc_dma_used);
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page_off = xdr->page_base;
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page_bytes = xdr->page_len + page_off;
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if (!page_bytes)
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goto encode_tail;
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/* Map the pages */
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vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off;
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vec->sge[sge_no].iov_len = page_bytes;
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sge_no++;
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while (page_bytes) {
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struct page *page;
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page = xdr->pages[page_no++];
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sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off));
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page_bytes -= sge_bytes;
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frmr->page_list->page_list[page_no] =
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ib_dma_map_page(xprt->sc_cm_id->device, page, 0,
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PAGE_SIZE, DMA_TO_DEVICE);
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if (ib_dma_mapping_error(xprt->sc_cm_id->device,
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frmr->page_list->page_list[page_no]))
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goto fatal_err;
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atomic_inc(&xprt->sc_dma_used);
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page_off = 0; /* reset for next time through loop */
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frmr->map_len += PAGE_SIZE;
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frmr->page_list_len++;
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}
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vec->count++;
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encode_tail:
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/* Map tail */
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if (0 == xdr->tail[0].iov_len)
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goto done;
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vec->count++;
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vec->sge[sge_no].iov_len = xdr->tail[0].iov_len;
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if (((unsigned long)xdr->tail[0].iov_base & PAGE_MASK) ==
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((unsigned long)xdr->head[0].iov_base & PAGE_MASK)) {
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/*
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* If head and tail use the same page, we don't need
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* to map it again.
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*/
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vec->sge[sge_no].iov_base = xdr->tail[0].iov_base;
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} else {
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void *va;
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/* Map another page for the tail */
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page_off = (unsigned long)xdr->tail[0].iov_base & ~PAGE_MASK;
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va = (void *)((unsigned long)xdr->tail[0].iov_base & PAGE_MASK);
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vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off;
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frmr->page_list->page_list[page_no] =
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ib_dma_map_single(xprt->sc_cm_id->device, va, PAGE_SIZE,
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DMA_TO_DEVICE);
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if (ib_dma_mapping_error(xprt->sc_cm_id->device,
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frmr->page_list->page_list[page_no]))
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goto fatal_err;
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atomic_inc(&xprt->sc_dma_used);
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frmr->map_len += PAGE_SIZE;
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frmr->page_list_len++;
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}
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done:
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if (svc_rdma_fastreg(xprt, frmr))
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goto fatal_err;
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return 0;
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fatal_err:
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printk("svcrdma: Error fast registering memory for xprt %p\n", xprt);
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svc_rdma_put_frmr(xprt, frmr);
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return -EIO;
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}
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static int map_xdr(struct svcxprt_rdma *xprt,
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struct xdr_buf *xdr,
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struct svc_rdma_req_map *vec)
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{
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int sge_max = (xdr->len+PAGE_SIZE-1) / PAGE_SIZE + 3;
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int sge_no;
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@ -83,6 +201,9 @@ static void xdr_to_sge(struct svcxprt_rdma *xprt,
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BUG_ON(xdr->len !=
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(xdr->head[0].iov_len + xdr->page_len + xdr->tail[0].iov_len));
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if (xprt->sc_frmr_pg_list_len)
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return fast_reg_xdr(xprt, xdr, vec);
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/* Skip the first sge, this is for the RPCRDMA header */
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sge_no = 1;
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@ -116,9 +237,12 @@ static void xdr_to_sge(struct svcxprt_rdma *xprt,
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BUG_ON(sge_no > sge_max);
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vec->count = sge_no;
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return 0;
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}
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/* Assumptions:
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* - We are using FRMR
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* - or -
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* - The specified write_len can be represented in sc_max_sge * PAGE_SIZE
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*/
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static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp,
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@ -158,30 +282,35 @@ static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp,
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sge_no = 0;
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/* Copy the remaining SGE */
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while (bc != 0 && xdr_sge_no < vec->count) {
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sge[sge_no].lkey = xprt->sc_phys_mr->lkey;
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sge_bytes = min((size_t)bc,
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(size_t)(vec->sge[xdr_sge_no].iov_len-sge_off));
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while (bc != 0) {
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sge_bytes = min_t(size_t,
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bc, vec->sge[xdr_sge_no].iov_len-sge_off);
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sge[sge_no].length = sge_bytes;
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atomic_inc(&xprt->sc_dma_used);
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sge[sge_no].addr =
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ib_dma_map_single(xprt->sc_cm_id->device,
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(void *)
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vec->sge[xdr_sge_no].iov_base + sge_off,
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sge_bytes, DMA_TO_DEVICE);
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if (dma_mapping_error(xprt->sc_cm_id->device->dma_device,
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sge[sge_no].addr))
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goto err;
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if (!vec->frmr) {
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sge[sge_no].addr =
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ib_dma_map_single(xprt->sc_cm_id->device,
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(void *)
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vec->sge[xdr_sge_no].iov_base + sge_off,
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sge_bytes, DMA_TO_DEVICE);
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if (ib_dma_mapping_error(xprt->sc_cm_id->device,
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sge[sge_no].addr))
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goto err;
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atomic_inc(&xprt->sc_dma_used);
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sge[sge_no].lkey = xprt->sc_dma_lkey;
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} else {
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sge[sge_no].addr = (unsigned long)
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vec->sge[xdr_sge_no].iov_base + sge_off;
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sge[sge_no].lkey = vec->frmr->mr->lkey;
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}
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ctxt->count++;
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ctxt->frmr = vec->frmr;
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sge_off = 0;
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sge_no++;
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ctxt->count++;
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xdr_sge_no++;
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BUG_ON(xdr_sge_no > vec->count);
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bc -= sge_bytes;
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}
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BUG_ON(bc != 0);
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BUG_ON(xdr_sge_no > vec->count);
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/* Prepare WRITE WR */
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memset(&write_wr, 0, sizeof write_wr);
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ctxt->wr_op = IB_WR_RDMA_WRITE;
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@ -226,7 +355,10 @@ static int send_write_chunks(struct svcxprt_rdma *xprt,
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res_ary = (struct rpcrdma_write_array *)
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&rdma_resp->rm_body.rm_chunks[1];
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max_write = xprt->sc_max_sge * PAGE_SIZE;
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if (vec->frmr)
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max_write = vec->frmr->map_len;
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else
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max_write = xprt->sc_max_sge * PAGE_SIZE;
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/* Write chunks start at the pagelist */
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for (xdr_off = rqstp->rq_res.head[0].iov_len, chunk_no = 0;
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@ -297,7 +429,10 @@ static int send_reply_chunks(struct svcxprt_rdma *xprt,
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res_ary = (struct rpcrdma_write_array *)
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&rdma_resp->rm_body.rm_chunks[2];
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max_write = xprt->sc_max_sge * PAGE_SIZE;
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if (vec->frmr)
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max_write = vec->frmr->map_len;
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else
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max_write = xprt->sc_max_sge * PAGE_SIZE;
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/* xdr offset starts at RPC message */
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for (xdr_off = 0, chunk_no = 0;
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@ -307,7 +442,6 @@ static int send_reply_chunks(struct svcxprt_rdma *xprt,
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ch = &arg_ary->wc_array[chunk_no].wc_target;
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write_len = min(xfer_len, ch->rs_length);
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/* Prepare the reply chunk given the length actually
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* written */
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rs_offset = get_unaligned(&(ch->rs_offset));
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@ -366,6 +500,7 @@ static int send_reply(struct svcxprt_rdma *rdma,
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int byte_count)
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{
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struct ib_send_wr send_wr;
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struct ib_send_wr inv_wr;
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int sge_no;
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int sge_bytes;
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int page_no;
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@ -385,27 +520,45 @@ static int send_reply(struct svcxprt_rdma *rdma,
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/* Prepare the context */
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ctxt->pages[0] = page;
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ctxt->count = 1;
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ctxt->frmr = vec->frmr;
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if (vec->frmr)
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set_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags);
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else
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clear_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags);
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/* Prepare the SGE for the RPCRDMA Header */
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atomic_inc(&rdma->sc_dma_used);
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ctxt->sge[0].addr =
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ib_dma_map_page(rdma->sc_cm_id->device,
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page, 0, PAGE_SIZE, DMA_TO_DEVICE);
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if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr))
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goto err;
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atomic_inc(&rdma->sc_dma_used);
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ctxt->direction = DMA_TO_DEVICE;
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ctxt->sge[0].length = svc_rdma_xdr_get_reply_hdr_len(rdma_resp);
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ctxt->sge[0].lkey = rdma->sc_phys_mr->lkey;
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ctxt->sge[0].lkey = rdma->sc_dma_lkey;
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/* Determine how many of our SGE are to be transmitted */
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for (sge_no = 1; byte_count && sge_no < vec->count; sge_no++) {
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sge_bytes = min_t(size_t, vec->sge[sge_no].iov_len, byte_count);
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byte_count -= sge_bytes;
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atomic_inc(&rdma->sc_dma_used);
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ctxt->sge[sge_no].addr =
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ib_dma_map_single(rdma->sc_cm_id->device,
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vec->sge[sge_no].iov_base,
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sge_bytes, DMA_TO_DEVICE);
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if (!vec->frmr) {
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ctxt->sge[sge_no].addr =
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ib_dma_map_single(rdma->sc_cm_id->device,
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vec->sge[sge_no].iov_base,
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sge_bytes, DMA_TO_DEVICE);
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if (ib_dma_mapping_error(rdma->sc_cm_id->device,
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ctxt->sge[sge_no].addr))
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goto err;
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atomic_inc(&rdma->sc_dma_used);
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ctxt->sge[sge_no].lkey = rdma->sc_dma_lkey;
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} else {
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ctxt->sge[sge_no].addr = (unsigned long)
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vec->sge[sge_no].iov_base;
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ctxt->sge[sge_no].lkey = vec->frmr->mr->lkey;
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}
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ctxt->sge[sge_no].length = sge_bytes;
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ctxt->sge[sge_no].lkey = rdma->sc_phys_mr->lkey;
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}
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BUG_ON(byte_count != 0);
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@ -417,11 +570,16 @@ static int send_reply(struct svcxprt_rdma *rdma,
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ctxt->pages[page_no+1] = rqstp->rq_respages[page_no];
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ctxt->count++;
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rqstp->rq_respages[page_no] = NULL;
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/* If there are more pages than SGE, terminate SGE list */
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/*
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* If there are more pages than SGE, terminate SGE
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* list so that svc_rdma_unmap_dma doesn't attempt to
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* unmap garbage.
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*/
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if (page_no+1 >= sge_no)
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ctxt->sge[page_no+1].length = 0;
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}
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BUG_ON(sge_no > rdma->sc_max_sge);
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BUG_ON(sge_no > ctxt->count);
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memset(&send_wr, 0, sizeof send_wr);
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ctxt->wr_op = IB_WR_SEND;
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send_wr.wr_id = (unsigned long)ctxt;
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@ -429,12 +587,26 @@ static int send_reply(struct svcxprt_rdma *rdma,
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send_wr.num_sge = sge_no;
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send_wr.opcode = IB_WR_SEND;
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send_wr.send_flags = IB_SEND_SIGNALED;
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if (vec->frmr) {
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/* Prepare INVALIDATE WR */
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memset(&inv_wr, 0, sizeof inv_wr);
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inv_wr.opcode = IB_WR_LOCAL_INV;
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inv_wr.send_flags = IB_SEND_SIGNALED;
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inv_wr.ex.invalidate_rkey =
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vec->frmr->mr->lkey;
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send_wr.next = &inv_wr;
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}
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ret = svc_rdma_send(rdma, &send_wr);
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if (ret)
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svc_rdma_put_context(ctxt, 1);
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goto err;
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return ret;
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return 0;
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err:
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svc_rdma_put_frmr(rdma, vec->frmr);
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svc_rdma_put_context(ctxt, 1);
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return -EIO;
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}
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void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp)
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@ -477,8 +649,9 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
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ctxt = svc_rdma_get_context(rdma);
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ctxt->direction = DMA_TO_DEVICE;
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vec = svc_rdma_get_req_map();
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xdr_to_sge(rdma, &rqstp->rq_res, vec);
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ret = map_xdr(rdma, &rqstp->rq_res, vec);
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if (ret)
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goto err0;
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inline_bytes = rqstp->rq_res.len;
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/* Create the RDMA response header */
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@ -498,7 +671,7 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
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if (ret < 0) {
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printk(KERN_ERR "svcrdma: failed to send write chunks, rc=%d\n",
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ret);
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goto error;
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goto err1;
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}
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inline_bytes -= ret;
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@ -508,7 +681,7 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
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if (ret < 0) {
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printk(KERN_ERR "svcrdma: failed to send reply chunks, rc=%d\n",
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ret);
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goto error;
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goto err1;
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}
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inline_bytes -= ret;
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|
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@ -517,9 +690,11 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
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svc_rdma_put_req_map(vec);
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dprintk("svcrdma: send_reply returns %d\n", ret);
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return ret;
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error:
|
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err1:
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put_page(res_page);
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err0:
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svc_rdma_put_req_map(vec);
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svc_rdma_put_context(ctxt, 0);
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put_page(res_page);
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return ret;
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}
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|
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|
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@ -335,6 +335,8 @@ static void process_context(struct svcxprt_rdma *xprt,
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|
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switch (ctxt->wr_op) {
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case IB_WR_SEND:
|
||||
if (test_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags))
|
||||
svc_rdma_put_frmr(xprt, ctxt->frmr);
|
||||
svc_rdma_put_context(ctxt, 1);
|
||||
break;
|
||||
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче