OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

iommu/dma: Use NUMA aware memory allocations in __iommu_dma_alloc_pages() 

Change function __iommu_dma_alloc_pages() to allocate pages for DMA from
respective device NUMA node. The ternary operator which would be for
alloc_pages_node() is tidied along with this.

The motivation for this change is to have a policy for page allocation
consistent with direct DMA mapping, which attempts to allocate pages local
to the device, as mentioned in [1].

In addition, for certain workloads it has been observed a marginal
performance improvement. The patch caused an observation of 0.9% average
throughput improvement for running tcrypt with HiSilicon crypto engine.

We also include a modification to use kvzalloc() for kzalloc()/vzalloc()
combination.

[1] https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1692998.html

Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
[JPG: Added kvzalloc(), drop pages ** being device local, remove ternary operator, update message]
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Ganapatrao Kulkarni 2018-11-30 19:14:00 +08:00 committed by Joerg Roedel
parent 51eb78098a
commit c4b17afb0a
1 changed files with 10 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
drivers/iommu/dma-iommu.c
View File

@ -449,20 +449,17 @@ static void __iommu_dma_free_pages(struct page **pages, int count)
kvfree(pages);
}
static struct page **__iommu_dma_alloc_pages(unsigned int count,
unsigned long order_mask, gfp_t gfp)
static struct page **__iommu_dma_alloc_pages(struct device *dev,
unsigned int count, unsigned long order_mask, gfp_t gfp)
{
struct page **pages;
unsigned int i = 0, array_size = count * sizeof(*pages);
unsigned int i = 0, nid = dev_to_node(dev);
order_mask &= (2U << MAX_ORDER) - 1;
if (!order_mask)
return NULL;
if (array_size <= PAGE_SIZE)
pages = kzalloc(array_size, GFP_KERNEL);
else
pages = vzalloc(array_size);
pages = kvzalloc(count * sizeof(*pages), GFP_KERNEL);
if (!pages)
return NULL;
@ -481,10 +478,12 @@ static struct page **__iommu_dma_alloc_pages(unsigned int count,
for (order_mask &= (2U << __fls(count)) - 1;
order_mask; order_mask &= ~order_size) {
unsigned int order = __fls(order_mask);
gfp_t alloc_flags = gfp;
order_size = 1U << order;
page = alloc_pages((order_mask - order_size) ?
gfp | __GFP_NORETRY : gfp, order);
if (order_mask > order_size)
alloc_flags |= __GFP_NORETRY;
page = alloc_pages_node(nid, alloc_flags, order);
if (!page)
continue;
if (!order)
@ -569,7 +568,8 @@ struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp,
alloc_sizes = min_size;
count = PAGE_ALIGN(size) >> PAGE_SHIFT;
pages = __iommu_dma_alloc_pages(count, alloc_sizes >> PAGE_SHIFT, gfp);
pages = __iommu_dma_alloc_pages(dev, count, alloc_sizes >> PAGE_SHIFT,
gfp);
if (!pages)
return NULL;