[PATCH v3] iommu/dma: Use NUMA aware memory allocations in __iommu_dma_alloc_pages()

From: John Garry
Date: Wed Nov 21 2018 - 09:52:55 EST


From: Ganapatrao Kulkarni <ganapatrao.kulkarni@xxxxxxxxxx>

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.

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

Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@xxxxxxxxxx>
[JPG: Added kvzalloc(), drop pages ** being device local, tidied ternary operator]
Signed-off-by: John Garry <john.garry@xxxxxxxxxx>

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index d1b0475..4afb1a8 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -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;

--
1.9.1