From 81fa1af31b5d79047821def6abdcb97a735d8a52 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Tue, 12 Nov 2019 16:22:29 -0400 Subject: [PATCH] drm/amdgpu: Use mmu_interval_notifier instead of hmm_mirror Convert the collision-retry lock around hmm_range_fault to use the one now provided by the mmu_interval notifier. Although this driver does not seem to use the collision retry lock that hmm provides correctly, it can still be converted over to use the mmu_interval_notifier api instead of hmm_mirror without too much trouble. This also deletes another place where a driver is associating additional data (struct amdgpu_mn) with a mmu_struct. Link: https://lore.kernel.org/r/20191112202231.3856-13-jgg@ziepe.ca Signed-off-by: Philip Yang Reviewed-by: Philip Yang Tested-by: Philip Yang Signed-off-by: Jason Gunthorpe --- drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 4 + drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 14 +-- drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c | 148 ++--------------------- drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h | 49 -------- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 116 +++++++++++------- 5 files changed, 94 insertions(+), 237 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c index 4770030..1bcedb9b 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c @@ -1738,6 +1738,10 @@ static int update_invalid_user_pages(struct amdkfd_process_info *process_info, return ret; } + /* + * FIXME: Cannot ignore the return code, must hold + * notifier_lock + */ amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm); /* Mark the BO as valid unless it was invalidated diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c index 82823d9..22c989b 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c @@ -603,8 +603,6 @@ static int amdgpu_cs_parser_bos(struct amdgpu_cs_parser *p, e->tv.num_shared = 2; amdgpu_bo_list_get_list(p->bo_list, &p->validated); - if (p->bo_list->first_userptr != p->bo_list->num_entries) - p->mn = amdgpu_mn_get(p->adev, AMDGPU_MN_TYPE_GFX); INIT_LIST_HEAD(&duplicates); amdgpu_vm_get_pd_bo(&fpriv->vm, &p->validated, &p->vm_pd); @@ -1287,11 +1285,11 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p, if (r) goto error_unlock; - /* No memory allocation is allowed while holding the mn lock. - * p->mn is hold until amdgpu_cs_submit is finished and fence is added - * to BOs. + /* No memory allocation is allowed while holding the notifier lock. + * The lock is held until amdgpu_cs_submit is finished and fence is + * added to BOs. */ - amdgpu_mn_lock(p->mn); + mutex_lock(&p->adev->notifier_lock); /* If userptr are invalidated after amdgpu_cs_parser_bos(), return * -EAGAIN, drmIoctl in libdrm will restart the amdgpu_cs_ioctl. @@ -1334,13 +1332,13 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p, amdgpu_vm_move_to_lru_tail(p->adev, &fpriv->vm); ttm_eu_fence_buffer_objects(&p->ticket, &p->validated, p->fence); - amdgpu_mn_unlock(p->mn); + mutex_unlock(&p->adev->notifier_lock); return 0; error_abort: drm_sched_job_cleanup(&job->base); - amdgpu_mn_unlock(p->mn); + mutex_unlock(&p->adev->notifier_lock); error_unlock: amdgpu_job_free(job); diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c index 9fe1c31..828b516 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c @@ -51,28 +51,6 @@ #include "amdgpu_amdkfd.h" /** - * amdgpu_mn_lock - take the write side lock for this notifier - * - * @mn: our notifier - */ -void amdgpu_mn_lock(struct amdgpu_mn *mn) -{ - if (mn) - down_write(&mn->lock); -} - -/** - * amdgpu_mn_unlock - drop the write side lock for this notifier - * - * @mn: our notifier - */ -void amdgpu_mn_unlock(struct amdgpu_mn *mn) -{ - if (mn) - up_write(&mn->lock); -} - -/** * amdgpu_mn_invalidate_gfx - callback to notify about mm change * * @mni: the range (mm) is about to update @@ -94,6 +72,9 @@ static bool amdgpu_mn_invalidate_gfx(struct mmu_interval_notifier *mni, return false; mutex_lock(&adev->notifier_lock); + + mmu_interval_set_seq(mni, cur_seq); + r = dma_resv_wait_timeout_rcu(bo->tbo.base.resv, true, false, MAX_SCHEDULE_TIMEOUT); mutex_unlock(&adev->notifier_lock); @@ -127,6 +108,9 @@ static bool amdgpu_mn_invalidate_hsa(struct mmu_interval_notifier *mni, return false; mutex_lock(&adev->notifier_lock); + + mmu_interval_set_seq(mni, cur_seq); + amdgpu_amdkfd_evict_userptr(bo->kfd_bo, bo->notifier.mm); mutex_unlock(&adev->notifier_lock); @@ -137,92 +121,6 @@ static const struct mmu_interval_notifier_ops amdgpu_mn_hsa_ops = { .invalidate = amdgpu_mn_invalidate_hsa, }; -static int amdgpu_mn_sync_pagetables(struct hmm_mirror *mirror, - const struct mmu_notifier_range *update) -{ - struct amdgpu_mn *amn = container_of(mirror, struct amdgpu_mn, mirror); - - if (!mmu_notifier_range_blockable(update)) - return -EAGAIN; - - down_read(&amn->lock); - up_read(&amn->lock); - return 0; -} - -/* Low bits of any reasonable mm pointer will be unused due to struct - * alignment. Use these bits to make a unique key from the mm pointer - * and notifier type. - */ -#define AMDGPU_MN_KEY(mm, type) ((unsigned long)(mm) + (type)) - -static struct hmm_mirror_ops amdgpu_hmm_mirror_ops[] = { - [AMDGPU_MN_TYPE_GFX] = { - .sync_cpu_device_pagetables = amdgpu_mn_sync_pagetables, - }, - [AMDGPU_MN_TYPE_HSA] = { - .sync_cpu_device_pagetables = amdgpu_mn_sync_pagetables, - }, -}; - -/** - * amdgpu_mn_get - create HMM mirror context - * - * @adev: amdgpu device pointer - * @type: type of MMU notifier context - * - * Creates a HMM mirror context for current->mm. - */ -struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev, - enum amdgpu_mn_type type) -{ - struct mm_struct *mm = current->mm; - struct amdgpu_mn *amn; - unsigned long key = AMDGPU_MN_KEY(mm, type); - int r; - - mutex_lock(&adev->mn_lock); - if (down_write_killable(&mm->mmap_sem)) { - mutex_unlock(&adev->mn_lock); - return ERR_PTR(-EINTR); - } - - hash_for_each_possible(adev->mn_hash, amn, node, key) - if (AMDGPU_MN_KEY(amn->mirror.hmm->mmu_notifier.mm, - amn->type) == key) - goto release_locks; - - amn = kzalloc(sizeof(*amn), GFP_KERNEL); - if (!amn) { - amn = ERR_PTR(-ENOMEM); - goto release_locks; - } - - amn->adev = adev; - init_rwsem(&amn->lock); - amn->type = type; - - amn->mirror.ops = &amdgpu_hmm_mirror_ops[type]; - r = hmm_mirror_register(&amn->mirror, mm); - if (r) - goto free_amn; - - hash_add(adev->mn_hash, &amn->node, AMDGPU_MN_KEY(mm, type)); - -release_locks: - up_write(&mm->mmap_sem); - mutex_unlock(&adev->mn_lock); - - return amn; - -free_amn: - up_write(&mm->mmap_sem); - mutex_unlock(&adev->mn_lock); - kfree(amn); - - return ERR_PTR(r); -} - /** * amdgpu_mn_register - register a BO for notifier updates * @@ -235,12 +133,12 @@ free_amn: int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr) { if (bo->kfd_bo) - bo->notifier.ops = &amdgpu_mn_hsa_ops; - else - bo->notifier.ops = &amdgpu_mn_gfx_ops; - - return mmu_interval_notifier_insert(&bo->notifier, addr, - amdgpu_bo_size(bo), current->mm); + return mmu_interval_notifier_insert(&bo->notifier, current->mm, + addr, amdgpu_bo_size(bo), + &amdgpu_mn_hsa_ops); + return mmu_interval_notifier_insert(&bo->notifier, current->mm, addr, + amdgpu_bo_size(bo), + &amdgpu_mn_gfx_ops); } /** @@ -257,25 +155,3 @@ void amdgpu_mn_unregister(struct amdgpu_bo *bo) mmu_interval_notifier_remove(&bo->notifier); bo->notifier.mm = NULL; } - -/* flags used by HMM internal, not related to CPU/GPU PTE flags */ -static const uint64_t hmm_range_flags[HMM_PFN_FLAG_MAX] = { - (1 << 0), /* HMM_PFN_VALID */ - (1 << 1), /* HMM_PFN_WRITE */ - 0 /* HMM_PFN_DEVICE_PRIVATE */ -}; - -static const uint64_t hmm_range_values[HMM_PFN_VALUE_MAX] = { - 0xfffffffffffffffeUL, /* HMM_PFN_ERROR */ - 0, /* HMM_PFN_NONE */ - 0xfffffffffffffffcUL /* HMM_PFN_SPECIAL */ -}; - -void amdgpu_hmm_init_range(struct hmm_range *range) -{ - if (range) { - range->flags = hmm_range_flags; - range->values = hmm_range_values; - range->pfn_shift = PAGE_SHIFT; - } -} diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h index d73ab29..a292238 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mn.h @@ -30,59 +30,10 @@ #include #include -enum amdgpu_mn_type { - AMDGPU_MN_TYPE_GFX, - AMDGPU_MN_TYPE_HSA, -}; - -/** - * struct amdgpu_mn - * - * @adev: amdgpu device pointer - * @type: type of MMU notifier - * @work: destruction work item - * @node: hash table node to find structure by adev and mn - * @lock: rw semaphore protecting the notifier nodes - * @mirror: HMM mirror function support - * - * Data for each amdgpu device and process address space. - */ -struct amdgpu_mn { - /* constant after initialisation */ - struct amdgpu_device *adev; - enum amdgpu_mn_type type; - - /* only used on destruction */ - struct work_struct work; - - /* protected by adev->mn_lock */ - struct hlist_node node; - - /* objects protected by lock */ - struct rw_semaphore lock; - -#ifdef CONFIG_HMM_MIRROR - /* HMM mirror */ - struct hmm_mirror mirror; -#endif -}; - #if defined(CONFIG_HMM_MIRROR) -void amdgpu_mn_lock(struct amdgpu_mn *mn); -void amdgpu_mn_unlock(struct amdgpu_mn *mn); -struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev, - enum amdgpu_mn_type type); int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr); void amdgpu_mn_unregister(struct amdgpu_bo *bo); -void amdgpu_hmm_init_range(struct hmm_range *range); #else -static inline void amdgpu_mn_lock(struct amdgpu_mn *mn) {} -static inline void amdgpu_mn_unlock(struct amdgpu_mn *mn) {} -static inline struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev, - enum amdgpu_mn_type type) -{ - return NULL; -} static inline int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr) { DRM_WARN_ONCE("HMM_MIRROR kernel config option is not enabled, " diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index c0e41f1..c41a26b 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -773,6 +773,20 @@ struct amdgpu_ttm_tt { #endif }; +#ifdef CONFIG_DRM_AMDGPU_USERPTR +/* flags used by HMM internal, not related to CPU/GPU PTE flags */ +static const uint64_t hmm_range_flags[HMM_PFN_FLAG_MAX] = { + (1 << 0), /* HMM_PFN_VALID */ + (1 << 1), /* HMM_PFN_WRITE */ + 0 /* HMM_PFN_DEVICE_PRIVATE */ +}; + +static const uint64_t hmm_range_values[HMM_PFN_VALUE_MAX] = { + 0xfffffffffffffffeUL, /* HMM_PFN_ERROR */ + 0, /* HMM_PFN_NONE */ + 0xfffffffffffffffcUL /* HMM_PFN_SPECIAL */ +}; + /** * amdgpu_ttm_tt_get_user_pages - get device accessible pages that back user * memory and start HMM tracking CPU page table update @@ -780,29 +794,28 @@ struct amdgpu_ttm_tt { * Calling function must call amdgpu_ttm_tt_userptr_range_done() once and only * once afterwards to stop HMM tracking */ -#if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR) - -#define MAX_RETRY_HMM_RANGE_FAULT 16 - int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) { - struct hmm_mirror *mirror = bo->mn ? &bo->mn->mirror : NULL; struct ttm_tt *ttm = bo->tbo.ttm; struct amdgpu_ttm_tt *gtt = (void *)ttm; - struct mm_struct *mm; unsigned long start = gtt->userptr; struct vm_area_struct *vma; struct hmm_range *range; + unsigned long timeout; + struct mm_struct *mm; unsigned long i; - uint64_t *pfns; int r = 0; - if (unlikely(!mirror)) { - DRM_DEBUG_DRIVER("Failed to get hmm_mirror\n"); + mm = bo->notifier.mm; + if (unlikely(!mm)) { + DRM_DEBUG_DRIVER("BO is not registered?\n"); return -EFAULT; } - mm = mirror->hmm->mmu_notifier.mm; + /* Another get_user_pages is running at the same time?? */ + if (WARN_ON(gtt->range)) + return -EFAULT; + if (!mmget_not_zero(mm)) /* Happens during process shutdown */ return -ESRCH; @@ -811,31 +824,23 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) r = -ENOMEM; goto out; } + range->notifier = &bo->notifier; + range->flags = hmm_range_flags; + range->values = hmm_range_values; + range->pfn_shift = PAGE_SHIFT; + range->start = bo->notifier.interval_tree.start; + range->end = bo->notifier.interval_tree.last + 1; + range->default_flags = hmm_range_flags[HMM_PFN_VALID]; + if (!amdgpu_ttm_tt_is_readonly(ttm)) + range->default_flags |= range->flags[HMM_PFN_WRITE]; - pfns = kvmalloc_array(ttm->num_pages, sizeof(*pfns), GFP_KERNEL); - if (unlikely(!pfns)) { + range->pfns = kvmalloc_array(ttm->num_pages, sizeof(*range->pfns), + GFP_KERNEL); + if (unlikely(!range->pfns)) { r = -ENOMEM; goto out_free_ranges; } - amdgpu_hmm_init_range(range); - range->default_flags = range->flags[HMM_PFN_VALID]; - range->default_flags |= amdgpu_ttm_tt_is_readonly(ttm) ? - 0 : range->flags[HMM_PFN_WRITE]; - range->pfn_flags_mask = 0; - range->pfns = pfns; - range->start = start; - range->end = start + ttm->num_pages * PAGE_SIZE; - - hmm_range_register(range, mirror); - - /* - * Just wait for range to be valid, safe to ignore return value as we - * will use the return value of hmm_range_fault() below under the - * mmap_sem to ascertain the validity of the range. - */ - hmm_range_wait_until_valid(range, HMM_RANGE_DEFAULT_TIMEOUT); - down_read(&mm->mmap_sem); vma = find_vma(mm, start); if (unlikely(!vma || start < vma->vm_start)) { @@ -847,18 +852,31 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) r = -EPERM; goto out_unlock; } + up_read(&mm->mmap_sem); + timeout = jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT); +retry: + range->notifier_seq = mmu_interval_read_begin(&bo->notifier); + + down_read(&mm->mmap_sem); r = hmm_range_fault(range, 0); up_read(&mm->mmap_sem); - - if (unlikely(r < 0)) + if (unlikely(r <= 0)) { + /* + * FIXME: This timeout should encompass the retry from + * mmu_interval_read_retry() as well. + */ + if ((r == 0 || r == -EBUSY) && !time_after(jiffies, timeout)) + goto retry; goto out_free_pfns; + } for (i = 0; i < ttm->num_pages; i++) { - pages[i] = hmm_device_entry_to_page(range, pfns[i]); + /* FIXME: The pages cannot be touched outside the notifier_lock */ + pages[i] = hmm_device_entry_to_page(range, range->pfns[i]); if (unlikely(!pages[i])) { pr_err("Page fault failed for pfn[%lu] = 0x%llx\n", - i, pfns[i]); + i, range->pfns[i]); r = -ENOMEM; goto out_free_pfns; @@ -873,8 +891,7 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages) out_unlock: up_read(&mm->mmap_sem); out_free_pfns: - hmm_range_unregister(range); - kvfree(pfns); + kvfree(range->pfns); out_free_ranges: kfree(range); out: @@ -903,15 +920,18 @@ bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm) "No user pages to check\n"); if (gtt->range) { - r = hmm_range_valid(gtt->range); - hmm_range_unregister(gtt->range); - + /* + * FIXME: Must always hold notifier_lock for this, and must + * not ignore the return code. + */ + r = mmu_interval_read_retry(gtt->range->notifier, + gtt->range->notifier_seq); kvfree(gtt->range->pfns); kfree(gtt->range); gtt->range = NULL; } - return r; + return !r; } #endif @@ -992,10 +1012,18 @@ static void amdgpu_ttm_tt_unpin_userptr(struct ttm_tt *ttm) sg_free_table(ttm->sg); #if IS_ENABLED(CONFIG_DRM_AMDGPU_USERPTR) - if (gtt->range && - ttm->pages[0] == hmm_device_entry_to_page(gtt->range, - gtt->range->pfns[0])) - WARN_ONCE(1, "Missing get_user_page_done\n"); + if (gtt->range) { + unsigned long i; + + for (i = 0; i < ttm->num_pages; i++) { + if (ttm->pages[i] != + hmm_device_entry_to_page(gtt->range, + gtt->range->pfns[i])) + break; + } + + WARN((i == ttm->num_pages), "Missing get_user_page_done\n"); + } #endif } -- 2.7.4