| Message ID | 1437608083-22898-2-git-send-email-jgunthorpe@obsidianresearch.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
On 7/23/2015 2:34 AM, Jason Gunthorpe wrote: > Every single ULP requires a local_dma_lkey to do anything with > a QP, so let us ensure one exists for every PD created. > > If the driver can supply a global local_dma_lkey then use that, otherwise > ask the driver to create a local use all physical memory MR associated > with the new PD. > > Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> > Reviewed-by: Sagi Grimberg <sagig@dev.mellanox.co.il> > Acked-by: Christoph Hellwig <hch@infradead.org> > --- > drivers/infiniband/core/verbs.c | 40 +++++++++++++++++++++++++++++++++++----- > include/rdma/ib_verbs.h | 2 ++ > 2 files changed, 37 insertions(+), 5 deletions(-) > > diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c > index bac3fb406a74..1ddf06314f36 100644 > --- a/drivers/infiniband/core/verbs.c > +++ b/drivers/infiniband/core/verbs.c > @@ -213,24 +213,54 @@ EXPORT_SYMBOL(rdma_port_get_link_layer); > > /* Protection domains */ > > +/* Return a pd for in-kernel use that has a local_dma_lkey which provides > + local access to all physical memory. */ Why not kdoc style? we need to move the ib_verbs.h kdocs here anyway. Might be a good chance to do that for ib_alloc_pd(). > struct ib_pd *ib_alloc_pd(struct ib_device *device) > { > struct ib_pd *pd; > + struct ib_device_attr devattr; > + int rc; > + > + rc = ib_query_device(device, &devattr); > + if (rc) > + return ERR_PTR(rc); > > pd = device->alloc_pd(device, NULL, NULL); > + if (IS_ERR(pd)) > + return pd; > + > + pd->device = device; > + pd->uobject = NULL; > + pd->local_mr = NULL; > + atomic_set(&pd->usecnt, 0); > + > + if (devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY) > + pd->local_dma_lkey = device->local_dma_lkey; > + else { > + struct ib_mr *mr; > + > + mr = ib_get_dma_mr(pd, IB_ACCESS_LOCAL_WRITE); > + if (IS_ERR(mr)) { > + ib_dealloc_pd(pd); > + return (struct ib_pd *)mr; > + } > > - if (!IS_ERR(pd)) { > - pd->device = device; > - pd->uobject = NULL; > - atomic_set(&pd->usecnt, 0); > + pd->local_mr = mr; > + pd->local_dma_lkey = pd->local_mr->lkey; > } > - > return pd; > } > + > EXPORT_SYMBOL(ib_alloc_pd); You have an extra newline here. > > int ib_dealloc_pd(struct ib_pd *pd) > { > + if (pd->local_mr) { > + if (ib_dereg_mr(pd->local_mr)) > + return -EBUSY; > + pd->local_mr = NULL; > + } > + > if (atomic_read(&pd->usecnt)) > return -EBUSY; > > diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h > index 986fddb08579..cfda95d7b067 100644 > --- a/include/rdma/ib_verbs.h > +++ b/include/rdma/ib_verbs.h > @@ -1255,6 +1255,8 @@ struct ib_pd { > struct ib_device *device; > struct ib_uobject *uobject; > atomic_t usecnt; /* count all resources */ > + struct ib_mr *local_mr; > + u32 local_dma_lkey; Maybe its better to place the local_dma_lkey in the first cacheline as it is normally accessed in the hot path? -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jul 23, 2015 at 01:47:02PM +0300, Sagi Grimberg wrote: > >+/* Return a pd for in-kernel use that has a local_dma_lkey which provides > >+ local access to all physical memory. */ > > Why not kdoc style? we need to move the ib_verbs.h kdocs here anyway. > Might be a good chance to do that for ib_alloc_pd(). Right, took care of these. > >diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h > >index 986fddb08579..cfda95d7b067 100644 > >+++ b/include/rdma/ib_verbs.h > >@@ -1255,6 +1255,8 @@ struct ib_pd { > > struct ib_device *device; > > struct ib_uobject *uobject; > > atomic_t usecnt; /* count all resources */ > >+ struct ib_mr *local_mr; > >+ u32 local_dma_lkey; > > Maybe its better to place the local_dma_lkey in the first cacheline as > it is normally accessed in the hot path? Sure, but it doesn't matter too much as it is probably the only hot item in the pd... At the very least is avoids computing an EA... I've posted an updated series on my github, none of this is a functional change, so I'm going to continue to wait for testing/reviewing of the various pieces before reposting such a big series. https://github.com/jgunthorpe/linux/commits/remove-ib_get_dma_mr Thanks, Jason -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c index bac3fb406a74..1ddf06314f36 100644 --- a/drivers/infiniband/core/verbs.c +++ b/drivers/infiniband/core/verbs.c @@ -213,24 +213,54 @@ EXPORT_SYMBOL(rdma_port_get_link_layer); /* Protection domains */ +/* Return a pd for in-kernel use that has a local_dma_lkey which provides + local access to all physical memory. */ struct ib_pd *ib_alloc_pd(struct ib_device *device) { struct ib_pd *pd; + struct ib_device_attr devattr; + int rc; + + rc = ib_query_device(device, &devattr); + if (rc) + return ERR_PTR(rc); pd = device->alloc_pd(device, NULL, NULL); + if (IS_ERR(pd)) + return pd; + + pd->device = device; + pd->uobject = NULL; + pd->local_mr = NULL; + atomic_set(&pd->usecnt, 0); + + if (devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY) + pd->local_dma_lkey = device->local_dma_lkey; + else { + struct ib_mr *mr; + + mr = ib_get_dma_mr(pd, IB_ACCESS_LOCAL_WRITE); + if (IS_ERR(mr)) { + ib_dealloc_pd(pd); + return (struct ib_pd *)mr; + } - if (!IS_ERR(pd)) { - pd->device = device; - pd->uobject = NULL; - atomic_set(&pd->usecnt, 0); + pd->local_mr = mr; + pd->local_dma_lkey = pd->local_mr->lkey; } - return pd; } + EXPORT_SYMBOL(ib_alloc_pd); int ib_dealloc_pd(struct ib_pd *pd) { + if (pd->local_mr) { + if (ib_dereg_mr(pd->local_mr)) + return -EBUSY; + pd->local_mr = NULL; + } + if (atomic_read(&pd->usecnt)) return -EBUSY; diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index 986fddb08579..cfda95d7b067 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -1255,6 +1255,8 @@ struct ib_pd { struct ib_device *device; struct ib_uobject *uobject; atomic_t usecnt; /* count all resources */ + struct ib_mr *local_mr; + u32 local_dma_lkey; }; struct ib_xrcd {