RDMA/core: Add weak ordering dma attr to dma mapping

For memory regions registered with IB_ACCESS_RELAXED_ORDERING will be dma
mapped with the DMA_ATTR_WEAK_ORDERING.

This will allow reads and writes to the mapping to be weakly ordered, such
change can enhance performance on some supporting architectures.

Link: https://lore.kernel.org/r/20200212073559.684139-1-leon@kernel.org
Signed-off-by: Michael Guralnik <michaelgur@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This commit is contained in:
Michael Guralnik 2020-02-12 09:35:59 +02:00 committed by Jason Gunthorpe
parent ca750d4a9c
commit f03d9fadfe

View File

@ -197,6 +197,7 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
unsigned long lock_limit;
unsigned long new_pinned;
unsigned long cur_base;
unsigned long dma_attr = 0;
struct mm_struct *mm;
unsigned long npages;
int ret;
@ -278,10 +279,12 @@ struct ib_umem *ib_umem_get(struct ib_device *device, unsigned long addr,
sg_mark_end(sg);
umem->nmap = ib_dma_map_sg(device,
umem->sg_head.sgl,
umem->sg_nents,
DMA_BIDIRECTIONAL);
if (access & IB_ACCESS_RELAXED_ORDERING)
dma_attr |= DMA_ATTR_WEAK_ORDERING;
umem->nmap =
ib_dma_map_sg_attrs(device, umem->sg_head.sgl, umem->sg_nents,
DMA_BIDIRECTIONAL, dma_attr);
if (!umem->nmap) {
ret = -ENOMEM;