Messages in this thread | | | Subject | Re: regression in ath10k dma allocation | From | Tobias Klausmann <> | Date | Tue, 20 Aug 2019 22:24:29 +0200 |
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On 20.08.19 09:12, Christoph Hellwig wrote: > On Tue, Aug 20, 2019 at 02:58:33PM +0800, Hillf Danton wrote: >> On Tue, 20 Aug 2019 05:05:14 +0200 Christoph Hellwig wrote: >>> Tobias, plase try this patch: >>> > New version below: > > --- > From b8a805e93be5a5662323b8ac61fe686df839c4ac Mon Sep 17 00:00:00 2001 > From: Christoph Hellwig <hch@lst.de> > Date: Tue, 20 Aug 2019 11:45:49 +0900 > Subject: dma-direct: fix zone selection after an unaddressable CMA allocation > > The new dma_alloc_contiguous hides if we allocate CMA or regular > pages, and thus fails to retry a ZONE_NORMAL allocation if the CMA > allocation succeeds but isn't addressable. That means we either fail > outright or dip into a small zone that might not succeed either. > > Thanks to Hillf Danton for debugging this issue. > > Fixes: b1d2dc009dec ("dma-contiguous: add dma_{alloc,free}_contiguous() helpers") > Reported-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de> > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/iommu/dma-iommu.c | 3 +++ > include/linux/dma-contiguous.h | 5 +---- > kernel/dma/contiguous.c | 9 +++------ > kernel/dma/direct.c | 10 +++++++++- > 4 files changed, 16 insertions(+), 11 deletions(-) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index d991d40f797f..f68a62c3c32b 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -965,10 +965,13 @@ static void *iommu_dma_alloc_pages(struct device *dev, size_t size, > { > bool coherent = dev_is_dma_coherent(dev); > size_t alloc_size = PAGE_ALIGN(size); > + int node = dev_to_node(dev); > struct page *page = NULL; > void *cpu_addr; > > page = dma_alloc_contiguous(dev, alloc_size, gfp); > + if (!page) > + page = alloc_pages_node(node, gfp, get_order(alloc_size)); > if (!page) > return NULL; > > diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h > index c05d4e661489..03f8e98e3bcc 100644 > --- a/include/linux/dma-contiguous.h > +++ b/include/linux/dma-contiguous.h > @@ -160,10 +160,7 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages, > static inline struct page *dma_alloc_contiguous(struct device *dev, size_t size, > gfp_t gfp) > { > - int node = dev ? dev_to_node(dev) : NUMA_NO_NODE; > - size_t align = get_order(PAGE_ALIGN(size)); > - > - return alloc_pages_node(node, gfp, align); > + return NULL; > } > > static inline void dma_free_contiguous(struct device *dev, struct page *page, > diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c > index 2bd410f934b3..e6b450fdbeb6 100644 > --- a/kernel/dma/contiguous.c > +++ b/kernel/dma/contiguous.c > @@ -230,9 +230,7 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages, > */ > struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp) > { > - int node = dev ? dev_to_node(dev) : NUMA_NO_NODE; > - size_t count = PAGE_ALIGN(size) >> PAGE_SHIFT; > - size_t align = get_order(PAGE_ALIGN(size)); > + size_t count = size >> PAGE_SHIFT; > struct page *page = NULL; > struct cma *cma = NULL; > > @@ -243,14 +241,12 @@ struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp) > > /* CMA can be used only in the context which permits sleeping */ > if (cma && gfpflags_allow_blocking(gfp)) { > + size_t align = get_order(size); > size_t cma_align = min_t(size_t, align, CONFIG_CMA_ALIGNMENT); > > page = cma_alloc(cma, count, cma_align, gfp & __GFP_NOWARN); > } > > - /* Fallback allocation of normal pages */ > - if (!page) > - page = alloc_pages_node(node, gfp, align); > return page; > } > > @@ -258,6 +254,7 @@ struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp) > * dma_free_contiguous() - release allocated pages > * @dev: Pointer to device for which the pages were allocated. > * @page: Pointer to the allocated pages. > + int node = dev ? dev_to_node(dev) : NUMA_NO_NODE; > * @size: Size of allocated pages. > * > * This function releases memory allocated by dma_alloc_contiguous(). As the > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c > index 795c9b095d75..706113c6bebc 100644 > --- a/kernel/dma/direct.c > +++ b/kernel/dma/direct.c > @@ -85,6 +85,8 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) > struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, > dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) > { > + size_t alloc_size = PAGE_ALIGN(size); > + int node = dev_to_node(dev); > struct page *page = NULL; > u64 phys_mask; > > @@ -95,8 +97,14 @@ struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, > gfp &= ~__GFP_ZERO; > gfp |= __dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask, > &phys_mask); > + page = dma_alloc_contiguous(dev, alloc_size, gfp); > + if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { > + dma_free_contiguous(dev, page, alloc_size); > + page = NULL; > + } > again: > - page = dma_alloc_contiguous(dev, size, gfp); > + if (!page) > + page = alloc_pages_node(node, gfp, get_order(alloc_size)); > if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { > dma_free_contiguous(dev, page, size); > page = NULL;
I can confirm this resolves the regression!
Tested-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>
Thanks for the work of all involved,
Tobias
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