[PATCH 16/16] nouveau: support THP migration to private memory

Add support for migrating transparent huge pages to and from device private memory.

Signed-off-by: Ralph Campbell rcampbell@nvidia.com --- drivers/gpu/drm/nouveau/nouveau_dmem.c | 171 +++++++++++++++++-------- drivers/gpu/drm/nouveau/nouveau_svm.c | 11 +- drivers/gpu/drm/nouveau/nouveau_svm.h | 3 +- 3 files changed, 127 insertions(+), 58 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_dmem.c b/drivers/gpu/drm/nouveau/nouveau_dmem.c index f6a806ba3caa..e8c4c0bc78ae 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dmem.c +++ b/drivers/gpu/drm/nouveau/nouveau_dmem.c @@ -46,6 +46,7 @@ */ #define DMEM_CHUNK_SIZE (2UL << 20) #define DMEM_CHUNK_NPAGES (DMEM_CHUNK_SIZE >> PAGE_SHIFT) +#define PMD_ORDER (PMD_SHIFT - PAGE_SHIFT)

enum nouveau_aper { NOUVEAU_APER_VIRT, @@ -53,7 +54,7 @@ enum nouveau_aper { NOUVEAU_APER_HOST, };

-typedef int (*nouveau_migrate_copy_t)(struct nouveau_drm *drm, u64 npages, +typedef int (*nouveau_migrate_copy_t)(struct nouveau_drm *drm, u32 length, enum nouveau_aper, u64 dst_addr, enum nouveau_aper, u64 src_addr); typedef int (*nouveau_clear_page_t)(struct nouveau_drm *drm, u32 length, @@ -79,6 +80,7 @@ struct nouveau_dmem { struct list_head chunks; struct mutex mutex; struct page *free_pages; + struct page *free_huge_pages; spinlock_t lock; };

@@ -109,8 +111,13 @@ static void nouveau_dmem_page_free(struct page *page) struct nouveau_dmem *dmem = chunk->drm->dmem;

spin_lock(&dmem->lock); - page->zone_device_data = dmem->free_pages; - dmem->free_pages = page; + if (PageHuge(page)) { + page->zone_device_data = dmem->free_huge_pages; + dmem->free_huge_pages = page; + } else { + page->zone_device_data = dmem->free_pages; + dmem->free_pages = page; + }

WARN_ON(!chunk->callocated); chunk->callocated--; @@ -136,33 +143,41 @@ static void nouveau_dmem_fence_done(struct nouveau_fence **fence)

static vm_fault_t nouveau_dmem_fault_copy_one(struct nouveau_drm *drm, struct vm_fault *vmf, struct migrate_vma *args, - dma_addr_t *dma_addr) + dma_addr_t *dma_addr, size_t *sizep) { struct device *dev = drm->dev->dev; struct page *dpage, *spage; + unsigned int order;

spage = migrate_pfn_to_page(args->src[0]); if (!spage || !(args->src[0] & MIGRATE_PFN_MIGRATE)) return 0;

- dpage = alloc_page_vma(GFP_HIGHUSER, vmf->vma, vmf->address); + order = compound_order(spage); + if (order) + dpage = alloc_transhugepage(vmf->vma, vmf->address); + else + dpage = alloc_page_vma(GFP_HIGHUSER, vmf->vma, vmf->address); if (!dpage) return VM_FAULT_SIGBUS; + WARN_ON_ONCE(order != compound_order(dpage)); lock_page(dpage);

- *dma_addr = dma_map_page(dev, dpage, 0, PAGE_SIZE, DMA_BIDIRECTIONAL); + *sizep = page_size(dpage); + *dma_addr = dma_map_page(dev, dpage, 0, *sizep, DMA_BIDIRECTIONAL); if (dma_mapping_error(dev, *dma_addr)) goto error_free_page;

- if (drm->dmem->migrate.copy_func(drm, 1, NOUVEAU_APER_HOST, *dma_addr, - NOUVEAU_APER_VRAM, nouveau_dmem_page_addr(spage))) + if (drm->dmem->migrate.copy_func(drm, page_size(spage), + NOUVEAU_APER_HOST, *dma_addr, NOUVEAU_APER_VRAM, + nouveau_dmem_page_addr(spage))) goto error_dma_unmap;

args->dst[0] = migrate_pfn(page_to_pfn(dpage)) | MIGRATE_PFN_LOCKED; return 0;

error_dma_unmap: - dma_unmap_page(dev, *dma_addr, PAGE_SIZE, DMA_BIDIRECTIONAL); + dma_unmap_page(dev, *dma_addr, page_size(dpage), DMA_BIDIRECTIONAL); error_free_page: __free_page(dpage); return VM_FAULT_SIGBUS; @@ -173,8 +188,11 @@ static vm_fault_t nouveau_dmem_migrate_to_ram(struct vm_fault *vmf) struct nouveau_drm *drm = page_to_drm(vmf->page); struct nouveau_dmem *dmem = drm->dmem; struct nouveau_fence *fence; + struct page *page; + unsigned int order; unsigned long src = 0, dst = 0; dma_addr_t dma_addr = 0; + size_t size = 0; vm_fault_t ret; struct migrate_vma args = { .vma = vmf->vma, @@ -185,26 +203,52 @@ static vm_fault_t nouveau_dmem_migrate_to_ram(struct vm_fault *vmf) .src_owner = drm->dev, };

+ /* + * If the page was migrated to the GPU as a huge page, migrate it + * back the same way. + * FIXME If there is thrashing, maybe we should migrate one page. + */ + page = compound_head(vmf->page); + order = compound_order(page); + if (order) { + args.start &= PAGE_MASK << order; + args.end = args.start + (PAGE_SIZE << order); + args.src = kcalloc(1U << order, sizeof(*args.src), GFP_KERNEL); + if (!args.src) + return VM_FAULT_OOM; + args.dst = kcalloc(1U << order, sizeof(*args.dst), GFP_KERNEL); + if (!args.dst) { + ret = VM_FAULT_OOM; + goto error_src; + } + } + /* * FIXME what we really want is to find some heuristic to migrate more * than just one page on CPU fault. When such fault happens it is very * likely that more surrounding page will CPU fault too. */ - if (migrate_vma_setup(&args) < 0) - return VM_FAULT_SIGBUS; - if (!args.cpages) - return 0; + if (migrate_vma_setup(&args) < 0) { + ret = VM_FAULT_SIGBUS; + goto error_dst; + }

- ret = nouveau_dmem_fault_copy_one(drm, vmf, &args, &dma_addr); - if (ret || dst == 0) + ret = nouveau_dmem_fault_copy_one(drm, vmf, &args, &dma_addr, &size); + if (ret) goto done;

nouveau_fence_new(dmem->migrate.chan, false, &fence); migrate_vma_pages(&args); nouveau_dmem_fence_done(&fence); - dma_unmap_page(drm->dev->dev, dma_addr, PAGE_SIZE, DMA_BIDIRECTIONAL); + dma_unmap_page(drm->dev->dev, dma_addr, size, DMA_BIDIRECTIONAL); done: migrate_vma_finalize(&args); +error_dst: + if (args.dst != &dst) + kfree(args.dst); +error_src: + if (args.src != &src) + kfree(args.src); return ret; }

@@ -213,8 +257,8 @@ static const struct dev_pagemap_ops nouveau_dmem_pagemap_ops = { .migrate_to_ram = nouveau_dmem_migrate_to_ram, };

-static int -nouveau_dmem_chunk_alloc(struct nouveau_drm *drm, struct page **ppage) +static int nouveau_dmem_chunk_alloc(struct nouveau_drm *drm, bool is_huge, + struct page **ppage) { struct nouveau_dmem_chunk *chunk; struct resource *res; @@ -266,16 +310,20 @@ nouveau_dmem_chunk_alloc(struct nouveau_drm *drm, struct page **ppage) pfn_first = chunk->pagemap.res.start >> PAGE_SHIFT; page = pfn_to_page(pfn_first); spin_lock(&drm->dmem->lock); - for (i = 0; i < DMEM_CHUNK_NPAGES - 1; ++i, ++page) { - page->zone_device_data = drm->dmem->free_pages; - drm->dmem->free_pages = page; - } + if (is_huge) + prep_compound_page(page, PMD_ORDER); + else + for (i = 0; i < DMEM_CHUNK_NPAGES - 1; ++i, ++page) { + page->zone_device_data = drm->dmem->free_pages; + drm->dmem->free_pages = page; + } *ppage = page; chunk->callocated++; spin_unlock(&drm->dmem->lock);

- NV_INFO(drm, "DMEM: registered %ldMB of device memory\n", - DMEM_CHUNK_SIZE >> 20); + NV_INFO(drm, "DMEM: registered %ldMB of %sdevice memory %lx %lx\n", + DMEM_CHUNK_SIZE >> 20, is_huge ? "huge " : "", pfn_first, + nouveau_dmem_page_addr(page));

return 0;

@@ -293,14 +341,20 @@ nouveau_dmem_chunk_alloc(struct nouveau_drm *drm, struct page **ppage) }

static struct page * -nouveau_dmem_page_alloc_locked(struct nouveau_drm *drm) +nouveau_dmem_page_alloc_locked(struct nouveau_drm *drm, bool is_huge) { struct nouveau_dmem_chunk *chunk; struct page *page = NULL; int ret;

spin_lock(&drm->dmem->lock); - if (drm->dmem->free_pages) { + if (is_huge && drm->dmem->free_huge_pages) { + page = drm->dmem->free_huge_pages; + drm->dmem->free_huge_pages = page->zone_device_data; + chunk = nouveau_page_to_chunk(page); + chunk->callocated++; + spin_unlock(&drm->dmem->lock); + } else if (!is_huge && drm->dmem->free_pages) { page = drm->dmem->free_pages; drm->dmem->free_pages = page->zone_device_data; chunk = nouveau_page_to_chunk(page); @@ -308,7 +362,7 @@ nouveau_dmem_page_alloc_locked(struct nouveau_drm *drm) spin_unlock(&drm->dmem->lock); } else { spin_unlock(&drm->dmem->lock); - ret = nouveau_dmem_chunk_alloc(drm, &page); + ret = nouveau_dmem_chunk_alloc(drm, is_huge, &page); if (ret) return NULL; } @@ -381,19 +435,18 @@ nouveau_dmem_fini(struct nouveau_drm *drm) }

static int -nvc0b5_migrate_copy(struct nouveau_drm *drm, u64 npages, +nvc0b5_migrate_copy(struct nouveau_drm *drm, u32 length, enum nouveau_aper dst_aper, u64 dst_addr, enum nouveau_aper src_aper, u64 src_addr) { struct nouveau_channel *chan = drm->dmem->migrate.chan; - u32 launch_dma = (1 << 9) /* MULTI_LINE_ENABLE. */ | - (1 << 8) /* DST_MEMORY_LAYOUT_PITCH. */ | + u32 launch_dma = (1 << 8) /* DST_MEMORY_LAYOUT_PITCH. */ | (1 << 7) /* SRC_MEMORY_LAYOUT_PITCH. */ | (1 << 2) /* FLUSH_ENABLE_TRUE. */ | (2 << 0) /* DATA_TRANSFER_TYPE_NON_PIPELINED. */; int ret;

- ret = RING_SPACE(chan, 13); + ret = RING_SPACE(chan, 11); if (ret) return ret;

@@ -425,17 +478,15 @@ nvc0b5_migrate_copy(struct nouveau_drm *drm, u64 npages, launch_dma |= 0x00002000; /* DST_TYPE_PHYSICAL. */ }

- BEGIN_NVC0(chan, NvSubCopy, 0x0400, 8); - OUT_RING (chan, upper_32_bits(src_addr)); - OUT_RING (chan, lower_32_bits(src_addr)); - OUT_RING (chan, upper_32_bits(dst_addr)); - OUT_RING (chan, lower_32_bits(dst_addr)); - OUT_RING (chan, PAGE_SIZE); - OUT_RING (chan, PAGE_SIZE); - OUT_RING (chan, PAGE_SIZE); - OUT_RING (chan, npages); + BEGIN_NVC0(chan, NvSubCopy, 0x0400, 4); + OUT_RING(chan, upper_32_bits(src_addr)); + OUT_RING(chan, lower_32_bits(src_addr)); + OUT_RING(chan, upper_32_bits(dst_addr)); + OUT_RING(chan, lower_32_bits(dst_addr)); + BEGIN_NVC0(chan, NvSubCopy, 0x0418, 1); + OUT_RING(chan, length); BEGIN_NVC0(chan, NvSubCopy, 0x0300, 1); - OUT_RING (chan, launch_dma); + OUT_RING(chan, launch_dma); return 0; }

@@ -535,6 +586,7 @@ static unsigned long nouveau_dmem_migrate_copy_one(struct nouveau_drm *drm, struct device *dev = drm->dev->dev; struct page *dpage, *spage; unsigned long paddr; + unsigned long dst;

spage = migrate_pfn_to_page(src); if (!(src & MIGRATE_PFN_MIGRATE)) @@ -546,7 +598,8 @@ static unsigned long nouveau_dmem_migrate_copy_one(struct nouveau_drm *drm, goto done; }

- dpage = nouveau_dmem_page_alloc_locked(drm); + dpage = nouveau_dmem_page_alloc_locked(drm, + src & MIGRATE_PFN_COMPOUND); if (!dpage) goto out;

@@ -556,7 +609,7 @@ static unsigned long nouveau_dmem_migrate_copy_one(struct nouveau_drm *drm, DMA_BIDIRECTIONAL); if (dma_mapping_error(dev, *dma_addr)) goto out_free_page; - if (drm->dmem->migrate.copy_func(drm, 1, + if (drm->dmem->migrate.copy_func(drm, page_size(spage), NOUVEAU_APER_VRAM, paddr, NOUVEAU_APER_HOST, *dma_addr)) goto out_dma_unmap; } else { @@ -571,10 +624,13 @@ static unsigned long nouveau_dmem_migrate_copy_one(struct nouveau_drm *drm, ((paddr >> PAGE_SHIFT) << NVIF_VMM_PFNMAP_V0_ADDR_SHIFT); if (src & MIGRATE_PFN_WRITE) *pfn |= NVIF_VMM_PFNMAP_V0_W; - return migrate_pfn(page_to_pfn(dpage)) | MIGRATE_PFN_LOCKED; + dst = migrate_pfn(page_to_pfn(dpage)) | MIGRATE_PFN_LOCKED; + if (PageHead(dpage)) + dst |= MIGRATE_PFN_COMPOUND; + return dst;

out_dma_unmap: - dma_unmap_page(dev, *dma_addr, PAGE_SIZE, DMA_BIDIRECTIONAL); + dma_unmap_page(dev, *dma_addr, page_size(spage), DMA_BIDIRECTIONAL); out_free_page: nouveau_dmem_page_free_locked(drm, dpage); out: @@ -588,24 +644,30 @@ static void nouveau_dmem_migrate_chunk(struct nouveau_drm *drm, { struct nouveau_fence *fence; unsigned long addr = args->start, nr_dma = 0, i; + unsigned int page_shift = PAGE_SHIFT;

for (i = 0; addr < args->end; i++) { args->dst[i] = nouveau_dmem_migrate_copy_one(drm, args->src[i], dma_addrs + nr_dma, pfns + i); if (!dma_mapping_error(drm->dev->dev, dma_addrs[nr_dma])) nr_dma++; + if (args->dst[i] & MIGRATE_PFN_COMPOUND) { + page_shift = PMD_SHIFT; + i++; + break; + } addr += PAGE_SIZE; }

nouveau_fence_new(drm->dmem->migrate.chan, false, &fence); migrate_vma_pages(args); nouveau_dmem_fence_done(&fence); - nouveau_pfns_map(svmm, args->vma->vm_mm, args->start, pfns, i); + nouveau_pfns_map(svmm, args->vma->vm_mm, args->start, pfns, i, + page_shift);

- while (nr_dma--) { - dma_unmap_page(drm->dev->dev, dma_addrs[nr_dma], PAGE_SIZE, - DMA_BIDIRECTIONAL); - } + while (nr_dma) + dma_unmap_page(drm->dev->dev, dma_addrs[--nr_dma], + 1UL << page_shift, DMA_BIDIRECTIONAL); migrate_vma_finalize(args); }

@@ -617,7 +679,7 @@ nouveau_dmem_migrate_vma(struct nouveau_drm *drm, unsigned long end) { unsigned long npages = (end - start) >> PAGE_SHIFT; - unsigned long max = min(SG_MAX_SINGLE_ALLOC, npages); + unsigned long max = min(1UL << PMD_ORDER, npages); dma_addr_t *dma_addrs; struct migrate_vma args = { .vma = vma, @@ -646,8 +708,10 @@ nouveau_dmem_migrate_vma(struct nouveau_drm *drm, if (!pfns) goto out_free_dma;

- for (i = 0; i < npages; i += max) { - args.end = start + (max << PAGE_SHIFT); + for (; args.start < end; args.start = args.end) { + args.end = ALIGN(args.start, PMD_SIZE); + if (args.start == args.end) + args.end = min(end, args.start + PMD_SIZE); ret = migrate_vma_setup(&args); if (ret) goto out_free_pfns; @@ -655,7 +719,6 @@ nouveau_dmem_migrate_vma(struct nouveau_drm *drm, if (args.cpages) nouveau_dmem_migrate_chunk(drm, svmm, &args, dma_addrs, pfns); - args.start = args.end; }

ret = 0; diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c index a27625f3c5f9..f386a9318190 100644 --- a/drivers/gpu/drm/nouveau/nouveau_svm.c +++ b/drivers/gpu/drm/nouveau/nouveau_svm.c @@ -684,7 +684,6 @@ nouveau_svm_fault(struct nvif_notify *notify) nouveau_svm_fault_cancel_fault(svm, buffer->fault[fi]); continue; } - SVMM_DBG(svmm, "addr %016llx", buffer->fault[fi]->addr);

/* We try and group handling of faults within a small * window into a single update. @@ -736,6 +735,10 @@ nouveau_svm_fault(struct nvif_notify *notify) } mmput(mm);

+ SVMM_DBG(svmm, "addr %llx %s %c", buffer->fault[fi]->addr, + args.phys[0] & NVIF_VMM_PFNMAP_V0_VRAM ? + "vram" : "sysmem", + args.i.p.size > PAGE_SIZE ? 'H' : 'N'); limit = args.i.p.addr + args.i.p.size; for (fn = fi; ++fn < buffer->fault_nr; ) { /* It's okay to skip over duplicate addresses from the @@ -807,13 +810,15 @@ nouveau_pfns_free(u64 *pfns)

void nouveau_pfns_map(struct nouveau_svmm *svmm, struct mm_struct *mm, - unsigned long addr, u64 *pfns, unsigned long npages) + unsigned long addr, u64 *pfns, unsigned long npages, + unsigned int page_shift) { struct nouveau_pfnmap_args *args = nouveau_pfns_to_args(pfns); int ret;

args->p.addr = addr; - args->p.size = npages << PAGE_SHIFT; + args->p.page = page_shift; + args->p.size = npages << args->p.page;

mutex_lock(&svmm->mutex);

diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.h b/drivers/gpu/drm/nouveau/nouveau_svm.h index f0fcd1b72e8b..ba5927e445ad 100644 --- a/drivers/gpu/drm/nouveau/nouveau_svm.h +++ b/drivers/gpu/drm/nouveau/nouveau_svm.h @@ -22,7 +22,8 @@ int nouveau_svmm_bind(struct drm_device *, void *, struct drm_file *); u64 *nouveau_pfns_alloc(unsigned long npages); void nouveau_pfns_free(u64 *pfns); void nouveau_pfns_map(struct nouveau_svmm *svmm, struct mm_struct *mm, - unsigned long addr, u64 *pfns, unsigned long npages); + unsigned long addr, u64 *pfns, unsigned long npages, + unsigned int page_shift); #else /* IS_ENABLED(CONFIG_DRM_NOUVEAU_SVM) */ static inline void nouveau_svm_init(struct nouveau_drm *drm) {} static inline void nouveau_svm_fini(struct nouveau_drm *drm) {}