diff options
author | Chuck Lever <chuck.lever@oracle.com> | 2016-11-29 11:04:58 -0500 |
---|---|---|
committer | J. Bruce Fields <bfields@redhat.com> | 2016-11-30 17:31:13 -0500 |
commit | dd6fd213b05e7a1f590b470500343dd97c3a32c1 (patch) | |
tree | d622a047d2990e6ef4da4b9665fb01805edb17cd /net/sunrpc | |
parent | e4eb42cecc6dc546aac888ee4913d59121e886ee (diff) |
svcrdma: Remove DMA map accounting
Clean up: sc_dma_used is not required for correct operation. It is
simply a debugging tool to report when svcrdma has leaked DMA maps.
However, manipulating an atomic has a measurable CPU cost, and DMA
map accounting specific to svcrdma will be meaningless once svcrdma
is converted to use the new generic r/w API.
A similar kind of debug accounting can be done simply by enabling
the IOMMU or by using CONFIG_DMA_API_DEBUG, CONFIG_IOMMU_DEBUG, and
CONFIG_IOMMU_LEAK.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'net/sunrpc')
-rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 1 | ||||
-rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_transport.c | 13 |
2 files changed, 3 insertions, 11 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index 873c2a938d35..283246e0afc2 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -279,7 +279,6 @@ int rdma_read_chunk_frmr(struct svcxprt_rdma *xprt, frmr->sg); return -ENOMEM; } - atomic_inc(&xprt->sc_dma_used); n = ib_map_mr_sg(frmr->mr, frmr->sg, frmr->sg_nents, NULL, PAGE_SIZE); if (unlikely(n != frmr->sg_nents)) { diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index da990d7f8b20..a613ebd1dd85 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -224,25 +224,22 @@ void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt) struct svcxprt_rdma *xprt = ctxt->xprt; struct ib_device *device = xprt->sc_cm_id->device; u32 lkey = xprt->sc_pd->local_dma_lkey; - unsigned int i, count; + unsigned int i; - for (count = 0, i = 0; i < ctxt->mapped_sges; i++) { + for (i = 0; i < ctxt->mapped_sges; i++) { /* * Unmap the DMA addr in the SGE if the lkey matches * the local_dma_lkey, otherwise, ignore it since it is * an FRMR lkey and will be unmapped later when the * last WR that uses it completes. */ - if (ctxt->sge[i].lkey == lkey) { - count++; + if (ctxt->sge[i].lkey == lkey) ib_dma_unmap_page(device, ctxt->sge[i].addr, ctxt->sge[i].length, ctxt->direction); - } } ctxt->mapped_sges = 0; - atomic_sub(count, &xprt->sc_dma_used); } void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages) @@ -944,7 +941,6 @@ void svc_rdma_put_frmr(struct svcxprt_rdma *rdma, if (frmr) { ib_dma_unmap_sg(rdma->sc_cm_id->device, frmr->sg, frmr->sg_nents, frmr->direction); - atomic_dec(&rdma->sc_dma_used); spin_lock_bh(&rdma->sc_frmr_q_lock); WARN_ON_ONCE(!list_empty(&frmr->frmr_list)); list_add(&frmr->frmr_list, &rdma->sc_frmr_q); @@ -1256,9 +1252,6 @@ static void __svc_rdma_free(struct work_struct *work) if (rdma->sc_ctxt_used != 0) pr_err("svcrdma: ctxt still in use? (%d)\n", rdma->sc_ctxt_used); - if (atomic_read(&rdma->sc_dma_used) != 0) - pr_err("svcrdma: dma still in use? (%d)\n", - atomic_read(&rdma->sc_dma_used)); /* Final put of backchannel client transport */ if (xprt->xpt_bc_xprt) { |