diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.19.8/1175-drm-amdgpu-Transfer-fences-to-dmabuf-importer.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.19.8/1175-drm-amdgpu-Transfer-fences-to-dmabuf-importer.patch | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.19.8/1175-drm-amdgpu-Transfer-fences-to-dmabuf-importer.patch b/common/recipes-kernel/linux/linux-yocto-4.19.8/1175-drm-amdgpu-Transfer-fences-to-dmabuf-importer.patch new file mode 100644 index 00000000..60d745ee --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.19.8/1175-drm-amdgpu-Transfer-fences-to-dmabuf-importer.patch @@ -0,0 +1,126 @@ +From 998f596065c8a121cc34fdc13f24387a6494e18d Mon Sep 17 00:00:00 2001 +From: Chris Wilson <chris@chris-wilson.co.uk> +Date: Wed, 30 Jan 2019 10:55:17 +0000 +Subject: [PATCH 1175/2940] drm/amdgpu: Transfer fences to dmabuf importer +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +amdgpu only uses shared-fences internally, but dmabuf importers rely on +implicit write hazard tracking via the reservation_object.fence_excl. +For example, the importer use the write hazard for timing a page flip to +only occur after the exporter has finished flushing its write into the +surface. As such, on exporting a dmabuf, we must either flush all +outstanding fences (for we do not know which are writes and should have +been exclusive) or alternatively create a new exclusive fence that is +the composite of all the existing shared fences, and so will only be +signaled when all earlier fences are signaled (ensuring that we can not +be signaled before the completion of any earlier write). + +v2: reservation_object is already locked by amdgpu_bo_reserve() +v3: Replace looping with get_fences_rcu and special case the promotion +of a single shared fence directly to an exclusive fence, bypassing the +fence array. +v4: Drop the fence array ref after assigning to reservation_object + +Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107341 +Testcase: igt/amd_prime/amd-to-i915 +References: 8e94a46c1770 ("drm/amdgpu: Attach exclusive fence to prime exported bo's. (v5)") +Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> +Cc: Alex Deucher <alexander.deucher@amd.com> +Cc: "Christian König" <christian.koenig@amd.com> +Reviewed-by: "Christian König" <christian.koenig@amd.com> +Signed-off-by: Chaudhary Amit Kumar <Chaudharyamit.Kumar@amd.com> +--- + drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c | 59 ++++++++++++++++++++--- + 1 file changed, 51 insertions(+), 8 deletions(-) + +diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c +index e5a76a950290..60aac9afd3c8 100644 +--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c ++++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c +@@ -38,6 +38,7 @@ + #include "amdgpu_gem.h" + #include <drm/amdgpu_drm.h> + #include <linux/dma-buf.h> ++#include <linux/dma-fence-array.h> + + static const struct dma_buf_ops amdgpu_dmabuf_ops; + +@@ -189,6 +190,48 @@ amdgpu_gem_prime_import_sg_table(struct drm_device *dev, + return ERR_PTR(ret); + } + ++static int ++__reservation_object_make_exclusive(struct reservation_object *obj) ++{ ++ struct dma_fence **fences; ++ unsigned int count; ++ int r; ++ ++ if (!reservation_object_get_list(obj)) /* no shared fences to convert */ ++ return 0; ++ ++ r = reservation_object_get_fences_rcu(obj, NULL, &count, &fences); ++ if (r) ++ return r; ++ ++ if (count == 0) { ++ /* Now that was unexpected. */ ++ } else if (count == 1) { ++ reservation_object_add_excl_fence(obj, fences[0]); ++ dma_fence_put(fences[0]); ++ kfree(fences); ++ } else { ++ struct dma_fence_array *array; ++ ++ array = dma_fence_array_create(count, fences, ++ dma_fence_context_alloc(1), 0, ++ false); ++ if (!array) ++ goto err_fences_put; ++ ++ reservation_object_add_excl_fence(obj, &array->base); ++ dma_fence_put(&array->base); ++ } ++ ++ return 0; ++ ++err_fences_put: ++ while (count--) ++ dma_fence_put(fences[count]); ++ kfree(fences); ++ return -ENOMEM; ++} ++ + /** + * amdgpu_gem_map_attach - &dma_buf_ops.attach implementation + * @dma_buf: shared DMA buffer +@@ -220,16 +263,16 @@ static int amdgpu_gem_map_attach(struct dma_buf *dma_buf, + + if (attach->dev->driver != adev->dev->driver) { + /* +- * Wait for all shared fences to complete before we switch to future +- * use of exclusive fence on this prime shared bo. ++ * We only create shared fences for internal use, but importers ++ * of the dmabuf rely on exclusive fences for implicitly ++ * tracking write hazards. As any of the current fences may ++ * correspond to a write, we need to convert all existing ++ * fences on the reservation object into a single exclusive ++ * fence. + */ +- r = reservation_object_wait_timeout_rcu(bo->tbo.resv, +- true, false, +- MAX_SCHEDULE_TIMEOUT); +- if (unlikely(r < 0)) { +- DRM_DEBUG_PRIME("Fence wait failed: %li\n", r); ++ r = __reservation_object_make_exclusive(bo->tbo.resv); ++ if (r) + goto error_unreserve; +- } + } + + /* pin buffer into GTT */ +-- +2.17.1 + |