From: "Thomas Hellström" <thomas.hellstrom@linux.intel.com> To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: "Thomas Hellström" <thomas.hellstrom@linux.intel.com>, "Christian König" <christian.koenig@amd.com> Subject: [PATCH v2 09/15] drm/ttm, drm/amdgpu: Allow the driver some control over swapping Date: Tue, 18 May 2021 10:26:55 +0200 [thread overview] Message-ID: <20210518082701.997251-10-thomas.hellstrom@linux.intel.com> (raw) In-Reply-To: <20210518082701.997251-1-thomas.hellstrom@linux.intel.com> We are calling the eviction_valuable driver callback at eviction time to determine whether we actually can evict a buffer object. The upcoming i915 TTM backend needs the same functionality for swapout, and that might actually be beneficial to other drivers as well. Add an eviction_valuable call also in the swapout path. Try to keep the current behaviour for all drivers by returning true if the buffer object is already in the TTM_PL_SYSTEM placement. We change behaviour for the case where a buffer object is in a TT backed placement when swapped out, in which case the drivers normal eviction_valuable path is run. Finally export ttm_tt_unpopulate() and don't swap out bos that are not populated. This allows a driver to purge a bo at swapout time if its content is no longer valuable rather than to have TTM swap the contents out. Cc: Christian König <christian.koenig@amd.com> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 4 +++ drivers/gpu/drm/ttm/ttm_bo.c | 41 +++++++++++++++---------- drivers/gpu/drm/ttm/ttm_tt.c | 4 +++ 3 files changed, 33 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 8c7ec09eb1a4..d5a9d7a88315 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -1399,6 +1399,10 @@ static bool amdgpu_ttm_bo_eviction_valuable(struct ttm_buffer_object *bo, struct dma_fence *f; int i; + /* Swapout? */ + if (bo->mem.mem_type == TTM_PL_SYSTEM) + return true; + if (bo->type == ttm_bo_type_kernel && !amdgpu_vm_evictable(ttm_to_amdgpu_bo(bo))) return false; diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 4479c55aaa1d..6a3f3112f62a 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -531,6 +531,10 @@ static int ttm_bo_evict(struct ttm_buffer_object *bo, bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo, const struct ttm_place *place) { + dma_resv_assert_held(bo->base.resv); + if (bo->mem.mem_type == TTM_PL_SYSTEM) + return true; + /* Don't evict this BO if it's outside of the * requested placement range */ @@ -553,7 +557,9 @@ EXPORT_SYMBOL(ttm_bo_eviction_valuable); * b. Otherwise, trylock it. */ static bool ttm_bo_evict_swapout_allowable(struct ttm_buffer_object *bo, - struct ttm_operation_ctx *ctx, bool *locked, bool *busy) + struct ttm_operation_ctx *ctx, + const struct ttm_place *place, + bool *locked, bool *busy) { bool ret = false; @@ -571,6 +577,12 @@ static bool ttm_bo_evict_swapout_allowable(struct ttm_buffer_object *bo, *busy = !ret; } + if (ret && place && !bo->bdev->funcs->eviction_valuable(bo, place)) { + ret = false; + if (locked) + dma_resv_unlock(bo->base.resv); + } + return ret; } @@ -625,20 +637,14 @@ int ttm_mem_evict_first(struct ttm_device *bdev, list_for_each_entry(bo, &man->lru[i], lru) { bool busy; - if (!ttm_bo_evict_swapout_allowable(bo, ctx, &locked, - &busy)) { + if (!ttm_bo_evict_swapout_allowable(bo, ctx, place, + &locked, &busy)) { if (busy && !busy_bo && ticket != dma_resv_locking_ctx(bo->base.resv)) busy_bo = bo; continue; } - if (place && !bdev->funcs->eviction_valuable(bo, - place)) { - if (locked) - dma_resv_unlock(bo->base.resv); - continue; - } if (!ttm_bo_get_unless_zero(bo)) { if (locked) dma_resv_unlock(bo->base.resv); @@ -1138,10 +1144,18 @@ EXPORT_SYMBOL(ttm_bo_wait); int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx, gfp_t gfp_flags) { + struct ttm_place place = {}; bool locked; int ret; - if (!ttm_bo_evict_swapout_allowable(bo, ctx, &locked, NULL)) + /* + * While the bo may already reside in SYSTEM placement, set + * SYSTEM as new placement to cover also the move further below. + * The driver may use the fact that we're moving from SYSTEM + * as an indication that we're about to swap out. + */ + place.mem_type = TTM_PL_SYSTEM; + if (!ttm_bo_evict_swapout_allowable(bo, ctx, &place, &locked, NULL)) return -EBUSY; if (!ttm_bo_get_unless_zero(bo)) { @@ -1166,12 +1180,7 @@ int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx, if (bo->mem.mem_type != TTM_PL_SYSTEM) { struct ttm_operation_ctx ctx = { false, false }; struct ttm_resource evict_mem; - struct ttm_place place, hop; - - memset(&place, 0, sizeof(place)); - memset(&hop, 0, sizeof(hop)); - - place.mem_type = TTM_PL_SYSTEM; + struct ttm_place hop = {}; ret = ttm_resource_alloc(bo, &place, &evict_mem); if (unlikely(ret)) diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c index 539e0232cb3b..7878ca4876c5 100644 --- a/drivers/gpu/drm/ttm/ttm_tt.c +++ b/drivers/gpu/drm/ttm/ttm_tt.c @@ -258,6 +258,9 @@ int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm, struct page *to_page; int i, ret; + if (!ttm_tt_is_populated(ttm)) + return 0; + swap_storage = shmem_file_setup("ttm swap", size, 0); if (IS_ERR(swap_storage)) { pr_err("Failed allocating swap storage\n"); @@ -399,6 +402,7 @@ void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm) ttm->page_flags &= ~TTM_PAGE_FLAG_PRIV_POPULATED; } +EXPORT_SYMBOL(ttm_tt_unpopulate); #ifdef CONFIG_DEBUG_FS -- 2.31.1
WARNING: multiple messages have this Message-ID (diff)
From: "Thomas Hellström" <thomas.hellstrom@linux.intel.com> To: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: "Thomas Hellström" <thomas.hellstrom@linux.intel.com>, "Christian König" <christian.koenig@amd.com> Subject: [Intel-gfx] [PATCH v2 09/15] drm/ttm, drm/amdgpu: Allow the driver some control over swapping Date: Tue, 18 May 2021 10:26:55 +0200 [thread overview] Message-ID: <20210518082701.997251-10-thomas.hellstrom@linux.intel.com> (raw) In-Reply-To: <20210518082701.997251-1-thomas.hellstrom@linux.intel.com> We are calling the eviction_valuable driver callback at eviction time to determine whether we actually can evict a buffer object. The upcoming i915 TTM backend needs the same functionality for swapout, and that might actually be beneficial to other drivers as well. Add an eviction_valuable call also in the swapout path. Try to keep the current behaviour for all drivers by returning true if the buffer object is already in the TTM_PL_SYSTEM placement. We change behaviour for the case where a buffer object is in a TT backed placement when swapped out, in which case the drivers normal eviction_valuable path is run. Finally export ttm_tt_unpopulate() and don't swap out bos that are not populated. This allows a driver to purge a bo at swapout time if its content is no longer valuable rather than to have TTM swap the contents out. Cc: Christian König <christian.koenig@amd.com> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 4 +++ drivers/gpu/drm/ttm/ttm_bo.c | 41 +++++++++++++++---------- drivers/gpu/drm/ttm/ttm_tt.c | 4 +++ 3 files changed, 33 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index 8c7ec09eb1a4..d5a9d7a88315 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -1399,6 +1399,10 @@ static bool amdgpu_ttm_bo_eviction_valuable(struct ttm_buffer_object *bo, struct dma_fence *f; int i; + /* Swapout? */ + if (bo->mem.mem_type == TTM_PL_SYSTEM) + return true; + if (bo->type == ttm_bo_type_kernel && !amdgpu_vm_evictable(ttm_to_amdgpu_bo(bo))) return false; diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index 4479c55aaa1d..6a3f3112f62a 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -531,6 +531,10 @@ static int ttm_bo_evict(struct ttm_buffer_object *bo, bool ttm_bo_eviction_valuable(struct ttm_buffer_object *bo, const struct ttm_place *place) { + dma_resv_assert_held(bo->base.resv); + if (bo->mem.mem_type == TTM_PL_SYSTEM) + return true; + /* Don't evict this BO if it's outside of the * requested placement range */ @@ -553,7 +557,9 @@ EXPORT_SYMBOL(ttm_bo_eviction_valuable); * b. Otherwise, trylock it. */ static bool ttm_bo_evict_swapout_allowable(struct ttm_buffer_object *bo, - struct ttm_operation_ctx *ctx, bool *locked, bool *busy) + struct ttm_operation_ctx *ctx, + const struct ttm_place *place, + bool *locked, bool *busy) { bool ret = false; @@ -571,6 +577,12 @@ static bool ttm_bo_evict_swapout_allowable(struct ttm_buffer_object *bo, *busy = !ret; } + if (ret && place && !bo->bdev->funcs->eviction_valuable(bo, place)) { + ret = false; + if (locked) + dma_resv_unlock(bo->base.resv); + } + return ret; } @@ -625,20 +637,14 @@ int ttm_mem_evict_first(struct ttm_device *bdev, list_for_each_entry(bo, &man->lru[i], lru) { bool busy; - if (!ttm_bo_evict_swapout_allowable(bo, ctx, &locked, - &busy)) { + if (!ttm_bo_evict_swapout_allowable(bo, ctx, place, + &locked, &busy)) { if (busy && !busy_bo && ticket != dma_resv_locking_ctx(bo->base.resv)) busy_bo = bo; continue; } - if (place && !bdev->funcs->eviction_valuable(bo, - place)) { - if (locked) - dma_resv_unlock(bo->base.resv); - continue; - } if (!ttm_bo_get_unless_zero(bo)) { if (locked) dma_resv_unlock(bo->base.resv); @@ -1138,10 +1144,18 @@ EXPORT_SYMBOL(ttm_bo_wait); int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx, gfp_t gfp_flags) { + struct ttm_place place = {}; bool locked; int ret; - if (!ttm_bo_evict_swapout_allowable(bo, ctx, &locked, NULL)) + /* + * While the bo may already reside in SYSTEM placement, set + * SYSTEM as new placement to cover also the move further below. + * The driver may use the fact that we're moving from SYSTEM + * as an indication that we're about to swap out. + */ + place.mem_type = TTM_PL_SYSTEM; + if (!ttm_bo_evict_swapout_allowable(bo, ctx, &place, &locked, NULL)) return -EBUSY; if (!ttm_bo_get_unless_zero(bo)) { @@ -1166,12 +1180,7 @@ int ttm_bo_swapout(struct ttm_buffer_object *bo, struct ttm_operation_ctx *ctx, if (bo->mem.mem_type != TTM_PL_SYSTEM) { struct ttm_operation_ctx ctx = { false, false }; struct ttm_resource evict_mem; - struct ttm_place place, hop; - - memset(&place, 0, sizeof(place)); - memset(&hop, 0, sizeof(hop)); - - place.mem_type = TTM_PL_SYSTEM; + struct ttm_place hop = {}; ret = ttm_resource_alloc(bo, &place, &evict_mem); if (unlikely(ret)) diff --git a/drivers/gpu/drm/ttm/ttm_tt.c b/drivers/gpu/drm/ttm/ttm_tt.c index 539e0232cb3b..7878ca4876c5 100644 --- a/drivers/gpu/drm/ttm/ttm_tt.c +++ b/drivers/gpu/drm/ttm/ttm_tt.c @@ -258,6 +258,9 @@ int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm, struct page *to_page; int i, ret; + if (!ttm_tt_is_populated(ttm)) + return 0; + swap_storage = shmem_file_setup("ttm swap", size, 0); if (IS_ERR(swap_storage)) { pr_err("Failed allocating swap storage\n"); @@ -399,6 +402,7 @@ void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm) ttm->page_flags &= ~TTM_PAGE_FLAG_PRIV_POPULATED; } +EXPORT_SYMBOL(ttm_tt_unpopulate); #ifdef CONFIG_DEBUG_FS -- 2.31.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
next prev parent reply other threads:[~2021-05-18 8:28 UTC|newest] Thread overview: 120+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-05-18 8:26 [PATCH v2 00/15] drm/i915: Move LMEM (VRAM) management over to TTM Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 8:26 ` [PATCH v2 01/15] drm/i915: Untangle the vma pages_mutex Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 11:12 ` Maarten Lankhorst 2021-05-18 11:12 ` [Intel-gfx] " Maarten Lankhorst 2021-05-18 11:28 ` Thomas Hellström 2021-05-18 11:28 ` [Intel-gfx] " Thomas Hellström 2021-05-18 8:26 ` [PATCH v2 02/15] drm/i915: Don't free shared locks while shared Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 11:18 ` Maarten Lankhorst 2021-05-18 11:18 ` [Intel-gfx] " Maarten Lankhorst 2021-05-18 11:30 ` Thomas Hellström (Intel) 2021-05-18 11:30 ` Thomas Hellström (Intel) 2021-05-18 8:26 ` [PATCH v2 03/15] drm/i915: Fix i915_sg_page_sizes to record dma segments rather than physical pages Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 8:46 ` Matthew Auld 2021-05-18 8:46 ` Matthew Auld 2021-05-18 8:26 ` [PATCH v2 04/15] drm/ttm: Export functions to initialize and finalize the ttm range manager standalone Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 9:03 ` Daniel Vetter 2021-05-18 9:03 ` [Intel-gfx] " Daniel Vetter 2021-05-18 11:51 ` Christian König 2021-05-18 11:51 ` [Intel-gfx] " Christian König 2021-05-18 13:06 ` Thomas Hellström 2021-05-18 13:06 ` [Intel-gfx] " Thomas Hellström 2021-05-18 13:11 ` Christian König 2021-05-18 13:11 ` [Intel-gfx] " Christian König 2021-05-18 8:26 ` [PATCH v2 05/15] drm/i915/ttm Initialize the ttm device and memory managers Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 9:05 ` Matthew Auld 2021-05-18 9:05 ` Matthew Auld 2021-05-18 9:09 ` Matthew Auld 2021-05-18 9:09 ` Matthew Auld 2021-05-18 9:12 ` Thomas Hellström 2021-05-18 9:12 ` Thomas Hellström 2021-05-18 8:26 ` [PATCH v2 06/15] drm/i915/ttm: Embed a ttm buffer object in the i915 gem object Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 11:44 ` Maarten Lankhorst 2021-05-18 11:44 ` [Intel-gfx] " Maarten Lankhorst 2021-05-18 8:26 ` [PATCH v2 07/15] drm/ttm: Export ttm_bo_tt_destroy() Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 11:46 ` Maarten Lankhorst 2021-05-18 11:46 ` [Intel-gfx] " Maarten Lankhorst 2021-05-18 12:01 ` Christian König 2021-05-18 12:01 ` [Intel-gfx] " Christian König 2021-05-18 8:26 ` [PATCH v2 08/15] drm/i915/ttm Add a generic TTM memcpy move for page-based iomem Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 11:55 ` Christian König 2021-05-18 11:55 ` [Intel-gfx] " Christian König 2021-05-18 12:04 ` Thomas Hellström 2021-05-18 12:04 ` [Intel-gfx] " Thomas Hellström 2021-05-18 12:09 ` Christian König 2021-05-18 12:09 ` [Intel-gfx] " Christian König 2021-05-18 12:52 ` Thomas Hellström 2021-05-18 12:52 ` [Intel-gfx] " Thomas Hellström 2021-05-18 13:08 ` Christian König 2021-05-18 13:08 ` [Intel-gfx] " Christian König 2021-05-18 13:24 ` Thomas Hellström 2021-05-18 13:24 ` [Intel-gfx] " Thomas Hellström 2021-05-18 13:26 ` Christian König 2021-05-18 13:26 ` [Intel-gfx] " Christian König 2021-05-18 8:26 ` Thomas Hellström [this message] 2021-05-18 8:26 ` [Intel-gfx] [PATCH v2 09/15] drm/ttm, drm/amdgpu: Allow the driver some control over swapping Thomas Hellström 2021-05-18 12:19 ` Maarten Lankhorst 2021-05-18 12:19 ` Maarten Lankhorst 2021-05-18 15:15 ` Thomas Hellström 2021-05-18 15:15 ` [Intel-gfx] " Thomas Hellström 2021-05-18 15:18 ` Christian König 2021-05-18 15:18 ` [Intel-gfx] " Christian König 2021-05-18 15:20 ` Thomas Hellström 2021-05-18 15:20 ` [Intel-gfx] " Thomas Hellström 2021-05-18 15:28 ` Christian König 2021-05-18 15:28 ` [Intel-gfx] " Christian König 2021-05-18 15:38 ` Thomas Hellström 2021-05-18 15:38 ` [Intel-gfx] " Thomas Hellström 2021-05-18 15:42 ` Christian König 2021-05-18 15:42 ` [Intel-gfx] " Christian König 2021-05-18 16:07 ` Thomas Hellström 2021-05-18 16:07 ` [Intel-gfx] " Thomas Hellström 2021-05-18 16:30 ` Christian König 2021-05-18 16:30 ` [Intel-gfx] " Christian König 2021-05-19 6:27 ` Thomas Hellström 2021-05-19 6:27 ` [Intel-gfx] " Thomas Hellström 2021-05-19 10:43 ` Christian König 2021-05-19 10:43 ` [Intel-gfx] " Christian König 2021-05-18 8:26 ` [PATCH v2 10/15] drm/i915/ttm: Introduce a TTM i915 gem object backend Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-19 9:53 ` Matthew Auld 2021-05-19 9:53 ` Matthew Auld 2021-05-19 11:29 ` Thomas Hellström 2021-05-19 11:29 ` Thomas Hellström 2021-05-18 8:26 ` [PATCH v2 11/15] drm/i915/lmem: Verify checks for lmem residency Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-19 10:04 ` Matthew Auld 2021-05-19 10:04 ` Matthew Auld 2021-05-18 8:26 ` [PATCH v2 12/15] drm/i915: Disable mmap ioctl for gen12+ Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 8:41 ` Thomas Hellström 2021-05-18 8:41 ` Thomas Hellström 2021-05-18 8:26 ` [PATCH v2 13/15] drm/ttm: Add BO and offset arguments for vm_access and vm_fault ttm handlers Thomas Hellström 2021-05-18 8:26 ` [Intel-gfx] " Thomas Hellström 2021-05-18 8:59 ` Thomas Hellström 2021-05-18 8:59 ` Thomas Hellström 2021-05-18 11:59 ` Christian König 2021-05-18 11:59 ` Christian König 2021-05-18 14:59 ` Thomas Hellström 2021-05-18 14:59 ` Thomas Hellström 2021-05-18 8:27 ` [PATCH v2 14/15] drm/i915: Use ttm mmap handling for ttm bo's Thomas Hellström 2021-05-18 8:27 ` [Intel-gfx] " Thomas Hellström 2021-05-18 9:17 ` Thomas Hellström 2021-05-18 9:17 ` Thomas Hellström 2021-05-18 8:27 ` [PATCH v2 15/15] drm/i915/ttm: Add io sgt caching to i915_ttm_io_mem_pfn Thomas Hellström 2021-05-18 8:27 ` [Intel-gfx] " Thomas Hellström 2021-05-18 9:33 ` Thomas Hellström 2021-05-18 9:33 ` Thomas Hellström 2021-05-18 8:44 ` [Intel-gfx] ✗ Fi.CI.CHECKPATCH: warning for drm/i915: Move LMEM (VRAM) management over to TTM (rev2) Patchwork 2021-05-18 8:47 ` [Intel-gfx] ✗ Fi.CI.SPARSE: " Patchwork 2021-05-18 9:14 ` [Intel-gfx] ✗ Fi.CI.BAT: failure " Patchwork 2021-05-18 17:02 ` [Intel-gfx] ✓ Fi.CI.IGT: success " Patchwork
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