On Wed, Apr 06, 2022 at 09:51:17AM +0200, Christian König wrote:
> Audit all the users of dma_resv_add_excl_fence() and make sure they
> reserve a shared slot also when only trying to add an exclusive fence.
>
> This is the next step towards handling the exclusive fence like a
> shared one.
>
> v2: fix missed case in amdgpu
> v3: and two more radeon, rename function
> v4: add one more case to TTM, fix i915 after rebase
>
> Signed-off-by: Christian König <christian.koe...@amd.com>
Ok I think it looks all reasonable now and complete afaict. But it's
tricky stuff.
Reviewed-by: Daniel Vetter <daniel.vet...@ffwll.ch>
> ---
> drivers/dma-buf/dma-resv.c | 10 +--
> drivers/dma-buf/st-dma-resv.c | 64 +++++++++----------
> .../gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 4 +-
> drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 8 +++
> drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 4 +-
> drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 2 +-
> drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c | 8 +--
> drivers/gpu/drm/i915/gem/i915_gem_clflush.c | 3 +-
> .../gpu/drm/i915/gem/i915_gem_execbuffer.c | 10 ++-
> drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c | 6 +-
> .../drm/i915/gem/selftests/i915_gem_migrate.c | 5 +-
> drivers/gpu/drm/i915/i915_vma.c | 10 ++-
> .../drm/i915/selftests/intel_memory_region.c | 7 ++
> drivers/gpu/drm/lima/lima_gem.c | 10 ++-
> drivers/gpu/drm/msm/msm_gem_submit.c | 18 +++---
> drivers/gpu/drm/nouveau/nouveau_fence.c | 8 +--
> drivers/gpu/drm/panfrost/panfrost_job.c | 4 ++
> drivers/gpu/drm/qxl/qxl_release.c | 2 +-
> drivers/gpu/drm/radeon/radeon_cs.c | 4 ++
> drivers/gpu/drm/radeon/radeon_object.c | 8 +++
> drivers/gpu/drm/radeon/radeon_vm.c | 2 +-
> drivers/gpu/drm/ttm/ttm_bo.c | 8 ++-
> drivers/gpu/drm/ttm/ttm_bo_util.c | 12 +++-
> drivers/gpu/drm/ttm/ttm_execbuf_util.c | 15 ++---
> drivers/gpu/drm/v3d/v3d_gem.c | 15 +++--
> drivers/gpu/drm/vc4/vc4_gem.c | 2 +-
> drivers/gpu/drm/vgem/vgem_fence.c | 12 ++--
> drivers/gpu/drm/virtio/virtgpu_gem.c | 9 +++
> drivers/gpu/drm/vmwgfx/vmwgfx_bo.c | 16 +++--
> include/linux/dma-resv.h | 4 +-
> 30 files changed, 176 insertions(+), 114 deletions(-)
>
> diff --git a/drivers/dma-buf/dma-resv.c b/drivers/dma-buf/dma-resv.c
> index 15ffac35439d..8c650b96357a 100644
> --- a/drivers/dma-buf/dma-resv.c
> +++ b/drivers/dma-buf/dma-resv.c
> @@ -152,7 +152,7 @@ static inline struct dma_resv_list
> *dma_resv_shared_list(struct dma_resv *obj)
> }
>
> /**
> - * dma_resv_reserve_shared - Reserve space to add shared fences to
> + * dma_resv_reserve_fences - Reserve space to add shared fences to
> * a dma_resv.
> * @obj: reservation object
> * @num_fences: number of fences we want to add
> @@ -167,7 +167,7 @@ static inline struct dma_resv_list
> *dma_resv_shared_list(struct dma_resv *obj)
> * RETURNS
> * Zero for success, or -errno
> */
> -int dma_resv_reserve_shared(struct dma_resv *obj, unsigned int num_fences)
> +int dma_resv_reserve_fences(struct dma_resv *obj, unsigned int num_fences)
> {
> struct dma_resv_list *old, *new;
> unsigned int i, j, k, max;
> @@ -230,7 +230,7 @@ int dma_resv_reserve_shared(struct dma_resv *obj,
> unsigned int num_fences)
>
> return 0;
> }
> -EXPORT_SYMBOL(dma_resv_reserve_shared);
> +EXPORT_SYMBOL(dma_resv_reserve_fences);
>
> #ifdef CONFIG_DEBUG_MUTEXES
> /**
> @@ -238,7 +238,7 @@ EXPORT_SYMBOL(dma_resv_reserve_shared);
> * @obj: the dma_resv object to reset
> *
> * Reset the number of pre-reserved shared slots to test that drivers do
> - * correct slot allocation using dma_resv_reserve_shared(). See also
> + * correct slot allocation using dma_resv_reserve_fences(). See also
> * &dma_resv_list.shared_max.
> */
> void dma_resv_reset_shared_max(struct dma_resv *obj)
> @@ -260,7 +260,7 @@ EXPORT_SYMBOL(dma_resv_reset_shared_max);
> * @fence: the shared fence to add
> *
> * Add a fence to a shared slot, @obj must be locked with dma_resv_lock(),
> and
> - * dma_resv_reserve_shared() has been called.
> + * dma_resv_reserve_fences() has been called.
> *
> * See also &dma_resv.fence for a discussion of the semantics.
> */
> diff --git a/drivers/dma-buf/st-dma-resv.c b/drivers/dma-buf/st-dma-resv.c
> index cbe999c6e7a6..d2e61f6ae989 100644
> --- a/drivers/dma-buf/st-dma-resv.c
> +++ b/drivers/dma-buf/st-dma-resv.c
> @@ -75,17 +75,16 @@ static int test_signaling(void *arg, bool shared)
> goto err_free;
> }
>
> - if (shared) {
> - r = dma_resv_reserve_shared(&resv, 1);
> - if (r) {
> - pr_err("Resv shared slot allocation failed\n");
> - goto err_unlock;
> - }
> + r = dma_resv_reserve_fences(&resv, 1);
> + if (r) {
> + pr_err("Resv shared slot allocation failed\n");
> + goto err_unlock;
> + }
>
> + if (shared)
> dma_resv_add_shared_fence(&resv, f);
> - } else {
> + else
> dma_resv_add_excl_fence(&resv, f);
> - }
>
> if (dma_resv_test_signaled(&resv, shared)) {
> pr_err("Resv unexpectedly signaled\n");
> @@ -134,17 +133,16 @@ static int test_for_each(void *arg, bool shared)
> goto err_free;
> }
>
> - if (shared) {
> - r = dma_resv_reserve_shared(&resv, 1);
> - if (r) {
> - pr_err("Resv shared slot allocation failed\n");
> - goto err_unlock;
> - }
> + r = dma_resv_reserve_fences(&resv, 1);
> + if (r) {
> + pr_err("Resv shared slot allocation failed\n");
> + goto err_unlock;
> + }
>
> + if (shared)
> dma_resv_add_shared_fence(&resv, f);
> - } else {
> + else
> dma_resv_add_excl_fence(&resv, f);
> - }
>
> r = -ENOENT;
> dma_resv_for_each_fence(&cursor, &resv, shared, fence) {
> @@ -206,18 +204,17 @@ static int test_for_each_unlocked(void *arg, bool
> shared)
> goto err_free;
> }
>
> - if (shared) {
> - r = dma_resv_reserve_shared(&resv, 1);
> - if (r) {
> - pr_err("Resv shared slot allocation failed\n");
> - dma_resv_unlock(&resv);
> - goto err_free;
> - }
> + r = dma_resv_reserve_fences(&resv, 1);
> + if (r) {
> + pr_err("Resv shared slot allocation failed\n");
> + dma_resv_unlock(&resv);
> + goto err_free;
> + }
>
> + if (shared)
> dma_resv_add_shared_fence(&resv, f);
> - } else {
> + else
> dma_resv_add_excl_fence(&resv, f);
> - }
> dma_resv_unlock(&resv);
>
> r = -ENOENT;
> @@ -290,18 +287,17 @@ static int test_get_fences(void *arg, bool shared)
> goto err_resv;
> }
>
> - if (shared) {
> - r = dma_resv_reserve_shared(&resv, 1);
> - if (r) {
> - pr_err("Resv shared slot allocation failed\n");
> - dma_resv_unlock(&resv);
> - goto err_resv;
> - }
> + r = dma_resv_reserve_fences(&resv, 1);
> + if (r) {
> + pr_err("Resv shared slot allocation failed\n");
> + dma_resv_unlock(&resv);
> + goto err_resv;
> + }
>
> + if (shared)
> dma_resv_add_shared_fence(&resv, f);
> - } else {
> + else
> dma_resv_add_excl_fence(&resv, f);
> - }
> dma_resv_unlock(&resv);
>
> r = dma_resv_get_fences(&resv, shared, &i, &fences);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> index 900ed2a7483b..98b1736bb221 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> @@ -1233,7 +1233,7 @@ static int init_kfd_vm(struct amdgpu_vm *vm, void
> **process_info,
> AMDGPU_FENCE_OWNER_KFD, false);
> if (ret)
> goto wait_pd_fail;
> - ret = dma_resv_reserve_shared(vm->root.bo->tbo.base.resv, 1);
> + ret = dma_resv_reserve_fences(vm->root.bo->tbo.base.resv, 1);
> if (ret)
> goto reserve_shared_fail;
> amdgpu_bo_fence(vm->root.bo,
> @@ -2571,7 +2571,7 @@ int amdgpu_amdkfd_add_gws_to_process(void *info, void
> *gws, struct kgd_mem **mem
> * Add process eviction fence to bo so they can
> * evict each other.
> */
> - ret = dma_resv_reserve_shared(gws_bo->tbo.base.resv, 1);
> + ret = dma_resv_reserve_fences(gws_bo->tbo.base.resv, 1);
> if (ret)
> goto reserve_shared_fail;
> amdgpu_bo_fence(gws_bo, &process_info->eviction_fence->base, true);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> index 25731719c627..6f57a2fd5fe3 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> @@ -1388,6 +1388,14 @@ void amdgpu_bo_fence(struct amdgpu_bo *bo, struct
> dma_fence *fence,
> bool shared)
> {
> struct dma_resv *resv = bo->tbo.base.resv;
> + int r;
> +
> + r = dma_resv_reserve_fences(resv, 1);
> + if (r) {
> + /* As last resort on OOM we block for the fence */
> + dma_fence_wait(fence, false);
> + return;
> + }
>
> if (shared)
> dma_resv_add_shared_fence(resv, fence);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> index 5d11978c162e..b13451255e8b 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
> @@ -2926,7 +2926,7 @@ int amdgpu_vm_init(struct amdgpu_device *adev, struct
> amdgpu_vm *vm)
> if (r)
> goto error_free_root;
>
> - r = dma_resv_reserve_shared(root_bo->tbo.base.resv, 1);
> + r = dma_resv_reserve_fences(root_bo->tbo.base.resv, 1);
> if (r)
> goto error_unreserve;
>
> @@ -3369,7 +3369,7 @@ bool amdgpu_vm_handle_fault(struct amdgpu_device *adev,
> u32 pasid,
> value = 0;
> }
>
> - r = dma_resv_reserve_shared(root->tbo.base.resv, 1);
> + r = dma_resv_reserve_fences(root->tbo.base.resv, 1);
> if (r) {
> pr_debug("failed %d to reserve fence slot\n", r);
> goto error_unlock;
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> index 3b8856b4cece..b3fc3e958227 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> @@ -548,7 +548,7 @@ svm_range_vram_node_new(struct amdgpu_device *adev,
> struct svm_range *prange,
> goto reserve_bo_failed;
> }
>
> - r = dma_resv_reserve_shared(bo->tbo.base.resv, 1);
> + r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
> if (r) {
> pr_debug("failed %d to reserve bo\n", r);
> amdgpu_bo_unreserve(bo);
> diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c
> b/drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c
> index 5f502c49aec2..53f7c78628a4 100644
> --- a/drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c
> +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_submit.c
> @@ -179,11 +179,9 @@ static int submit_fence_sync(struct etnaviv_gem_submit
> *submit)
> struct etnaviv_gem_submit_bo *bo = &submit->bos[i];
> struct dma_resv *robj = bo->obj->base.resv;
>
> - if (!(bo->flags & ETNA_SUBMIT_BO_WRITE)) {
> - ret = dma_resv_reserve_shared(robj, 1);
> - if (ret)
> - return ret;
> - }
> + ret = dma_resv_reserve_fences(robj, 1);
> + if (ret)
> + return ret;
>
> if (submit->flags & ETNA_SUBMIT_NO_IMPLICIT)
> continue;
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
> b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
> index ce91b23385cf..1fd0cc9ca213 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
> @@ -108,7 +108,8 @@ bool i915_gem_clflush_object(struct drm_i915_gem_object
> *obj,
> trace_i915_gem_object_clflush(obj);
>
> clflush = NULL;
> - if (!(flags & I915_CLFLUSH_SYNC))
> + if (!(flags & I915_CLFLUSH_SYNC) &&
> + dma_resv_reserve_fences(obj->base.resv, 1) == 0)
> clflush = clflush_work_create(obj);
> if (clflush) {
> i915_sw_fence_await_reservation(&clflush->base.chain,
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> index d42f437149c9..78f8797853ce 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
> @@ -998,11 +998,9 @@ static int eb_validate_vmas(struct i915_execbuffer *eb)
> }
> }
>
> - if (!(ev->flags & EXEC_OBJECT_WRITE)) {
> - err = dma_resv_reserve_shared(vma->obj->base.resv, 1);
> - if (err)
> - return err;
> - }
> + err = dma_resv_reserve_fences(vma->obj->base.resv, 1);
> + if (err)
> + return err;
>
> GEM_BUG_ON(drm_mm_node_allocated(&vma->node) &&
> eb_vma_misplaced(&eb->exec[i], vma, ev->flags));
> @@ -2303,7 +2301,7 @@ static int eb_parse(struct i915_execbuffer *eb)
> if (IS_ERR(batch))
> return PTR_ERR(batch);
>
> - err = dma_resv_reserve_shared(shadow->obj->base.resv, 1);
> + err = dma_resv_reserve_fences(shadow->obj->base.resv, 1);
> if (err)
> return err;
>
> diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
> b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
> index 1ebe6e4086a1..432ac74ff225 100644
> --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
> +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
> @@ -611,7 +611,11 @@ int i915_gem_obj_copy_ttm(struct drm_i915_gem_object
> *dst,
> assert_object_held(src);
> i915_deps_init(&deps, GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
>
> - ret = dma_resv_reserve_shared(src_bo->base.resv, 1);
> + ret = dma_resv_reserve_fences(src_bo->base.resv, 1);
> + if (ret)
> + return ret;
> +
> + ret = dma_resv_reserve_fences(dst_bo->base.resv, 1);
> if (ret)
> return ret;
>
> diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_migrate.c
> b/drivers/gpu/drm/i915/gem/selftests/i915_gem_migrate.c
> index d534141b2cf7..0e52eb87cd55 100644
> --- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_migrate.c
> +++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_migrate.c
> @@ -216,7 +216,10 @@ static int __igt_lmem_pages_migrate(struct intel_gt *gt,
> i915_gem_object_is_lmem(obj),
> 0xdeadbeaf, &rq);
> if (rq) {
> - dma_resv_add_excl_fence(obj->base.resv, &rq->fence);
> + err = dma_resv_reserve_fences(obj->base.resv, 1);
> + if (!err)
> + dma_resv_add_excl_fence(obj->base.resv,
> + &rq->fence);
> i915_gem_object_set_moving_fence(obj, &rq->fence);
> i915_request_put(rq);
> }
> diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
> index 94fcdb7bd21d..bae3423f58e8 100644
> --- a/drivers/gpu/drm/i915/i915_vma.c
> +++ b/drivers/gpu/drm/i915/i915_vma.c
> @@ -1819,6 +1819,12 @@ int _i915_vma_move_to_active(struct i915_vma *vma,
> intel_frontbuffer_put(front);
> }
>
> + if (!(flags & __EXEC_OBJECT_NO_RESERVE)) {
> + err = dma_resv_reserve_fences(vma->obj->base.resv, 1);
> + if (unlikely(err))
> + return err;
> + }
> +
> if (fence) {
> dma_resv_add_excl_fence(vma->obj->base.resv, fence);
> obj->write_domain = I915_GEM_DOMAIN_RENDER;
> @@ -1826,7 +1832,7 @@ int _i915_vma_move_to_active(struct i915_vma *vma,
> }
> } else {
> if (!(flags & __EXEC_OBJECT_NO_RESERVE)) {
> - err = dma_resv_reserve_shared(vma->obj->base.resv, 1);
> + err = dma_resv_reserve_fences(vma->obj->base.resv, 1);
> if (unlikely(err))
> return err;
> }
> @@ -2044,7 +2050,7 @@ int i915_vma_unbind_async(struct i915_vma *vma, bool
> trylock_vm)
> if (!obj->mm.rsgt)
> return -EBUSY;
>
> - err = dma_resv_reserve_shared(obj->base.resv, 1);
> + err = dma_resv_reserve_fences(obj->base.resv, 1);
> if (err)
> return -EBUSY;
>
> diff --git a/drivers/gpu/drm/i915/selftests/intel_memory_region.c
> b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
> index ba32893e0873..6114e013092b 100644
> --- a/drivers/gpu/drm/i915/selftests/intel_memory_region.c
> +++ b/drivers/gpu/drm/i915/selftests/intel_memory_region.c
> @@ -1043,6 +1043,13 @@ static int igt_lmem_write_cpu(void *arg)
> }
>
> i915_gem_object_lock(obj, NULL);
> +
> + err = dma_resv_reserve_fences(obj->base.resv, 1);
> + if (err) {
> + i915_gem_object_unlock(obj);
> + goto out_put;
> + }
> +
> /* Put the pages into a known state -- from the gpu for added fun */
> intel_engine_pm_get(engine);
> err = intel_context_migrate_clear(engine->gt->migrate.context, NULL,
> diff --git a/drivers/gpu/drm/lima/lima_gem.c b/drivers/gpu/drm/lima/lima_gem.c
> index 55bb1ec3c4f7..e0a11ee0e86d 100644
> --- a/drivers/gpu/drm/lima/lima_gem.c
> +++ b/drivers/gpu/drm/lima/lima_gem.c
> @@ -257,13 +257,11 @@ int lima_gem_get_info(struct drm_file *file, u32
> handle, u32 *va, u64 *offset)
> static int lima_gem_sync_bo(struct lima_sched_task *task, struct lima_bo *bo,
> bool write, bool explicit)
> {
> - int err = 0;
> + int err;
>
> - if (!write) {
> - err = dma_resv_reserve_shared(lima_bo_resv(bo), 1);
> - if (err)
> - return err;
> - }
> + err = dma_resv_reserve_fences(lima_bo_resv(bo), 1);
> + if (err)
> + return err;
>
> /* explicit sync use user passed dep fence */
> if (explicit)
> diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c
> b/drivers/gpu/drm/msm/msm_gem_submit.c
> index c6d60c8d286d..3164db8be893 100644
> --- a/drivers/gpu/drm/msm/msm_gem_submit.c
> +++ b/drivers/gpu/drm/msm/msm_gem_submit.c
> @@ -320,16 +320,14 @@ static int submit_fence_sync(struct msm_gem_submit
> *submit, bool no_implicit)
> struct drm_gem_object *obj = &submit->bos[i].obj->base;
> bool write = submit->bos[i].flags & MSM_SUBMIT_BO_WRITE;
>
> - if (!write) {
> - /* NOTE: _reserve_shared() must happen before
> - * _add_shared_fence(), which makes this a slightly
> - * strange place to call it. OTOH this is a
> - * convenient can-fail point to hook it in.
> - */
> - ret = dma_resv_reserve_shared(obj->resv, 1);
> - if (ret)
> - return ret;
> - }
> + /* NOTE: _reserve_shared() must happen before
> + * _add_shared_fence(), which makes this a slightly
> + * strange place to call it. OTOH this is a
> + * convenient can-fail point to hook it in.
> + */
> + ret = dma_resv_reserve_fences(obj->resv, 1);
> + if (ret)
> + return ret;
>
> /* exclusive fences must be ordered */
> if (no_implicit && !write)
> diff --git a/drivers/gpu/drm/nouveau/nouveau_fence.c
> b/drivers/gpu/drm/nouveau/nouveau_fence.c
> index a3a04e0d76ec..0268259e97eb 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_fence.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_fence.c
> @@ -346,11 +346,9 @@ nouveau_fence_sync(struct nouveau_bo *nvbo, struct
> nouveau_channel *chan,
> struct dma_resv *resv = nvbo->bo.base.resv;
> int i, ret;
>
> - if (!exclusive) {
> - ret = dma_resv_reserve_shared(resv, 1);
> - if (ret)
> - return ret;
> - }
> + ret = dma_resv_reserve_fences(resv, 1);
> + if (ret)
> + return ret;
>
> /* Waiting for the exclusive fence first causes performance regressions
> * under some circumstances. So manually wait for the shared ones first.
> diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c
> b/drivers/gpu/drm/panfrost/panfrost_job.c
> index a6925dbb6224..c34114560e49 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_job.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_job.c
> @@ -247,6 +247,10 @@ static int panfrost_acquire_object_fences(struct
> drm_gem_object **bos,
> int i, ret;
>
> for (i = 0; i < bo_count; i++) {
> + ret = dma_resv_reserve_fences(bos[i]->resv, 1);
> + if (ret)
> + return ret;
> +
> /* panfrost always uses write mode in its current uapi */
> ret = drm_sched_job_add_implicit_dependencies(job, bos[i],
> true);
> diff --git a/drivers/gpu/drm/qxl/qxl_release.c
> b/drivers/gpu/drm/qxl/qxl_release.c
> index 469979cd0341..cde1e8ddaeaa 100644
> --- a/drivers/gpu/drm/qxl/qxl_release.c
> +++ b/drivers/gpu/drm/qxl/qxl_release.c
> @@ -200,7 +200,7 @@ static int qxl_release_validate_bo(struct qxl_bo *bo)
> return ret;
> }
>
> - ret = dma_resv_reserve_shared(bo->tbo.base.resv, 1);
> + ret = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
> if (ret)
> return ret;
>
> diff --git a/drivers/gpu/drm/radeon/radeon_cs.c
> b/drivers/gpu/drm/radeon/radeon_cs.c
> index 9ed2b2700e0a..446f7bae54c4 100644
> --- a/drivers/gpu/drm/radeon/radeon_cs.c
> +++ b/drivers/gpu/drm/radeon/radeon_cs.c
> @@ -535,6 +535,10 @@ static int radeon_bo_vm_update_pte(struct
> radeon_cs_parser *p,
> return r;
>
> radeon_sync_fence(&p->ib.sync, bo_va->last_pt_update);
> +
> + r = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
> + if (r)
> + return r;
> }
>
> return radeon_vm_clear_invalids(rdev, vm);
> diff --git a/drivers/gpu/drm/radeon/radeon_object.c
> b/drivers/gpu/drm/radeon/radeon_object.c
> index 91a72cd14304..7ffd2e90f325 100644
> --- a/drivers/gpu/drm/radeon/radeon_object.c
> +++ b/drivers/gpu/drm/radeon/radeon_object.c
> @@ -782,6 +782,14 @@ void radeon_bo_fence(struct radeon_bo *bo, struct
> radeon_fence *fence,
> bool shared)
> {
> struct dma_resv *resv = bo->tbo.base.resv;
> + int r;
> +
> + r = dma_resv_reserve_fences(resv, 1);
> + if (r) {
> + /* As last resort on OOM we block for the fence */
> + dma_fence_wait(&fence->base, false);
> + return;
> + }
>
> if (shared)
> dma_resv_add_shared_fence(resv, &fence->base);
> diff --git a/drivers/gpu/drm/radeon/radeon_vm.c
> b/drivers/gpu/drm/radeon/radeon_vm.c
> index bb53016f3138..987cabbf1318 100644
> --- a/drivers/gpu/drm/radeon/radeon_vm.c
> +++ b/drivers/gpu/drm/radeon/radeon_vm.c
> @@ -831,7 +831,7 @@ static int radeon_vm_update_ptes(struct radeon_device
> *rdev,
> int r;
>
> radeon_sync_resv(rdev, &ib->sync, pt->tbo.base.resv, true);
> - r = dma_resv_reserve_shared(pt->tbo.base.resv, 1);
> + r = dma_resv_reserve_fences(pt->tbo.base.resv, 1);
> if (r)
> return r;
>
> diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
> index e5fd0f2c0299..c49996cf25d0 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo.c
> @@ -151,6 +151,10 @@ static int ttm_bo_handle_move_mem(struct
> ttm_buffer_object *bo,
> }
> }
>
> + ret = dma_resv_reserve_fences(bo->base.resv, 1);
> + if (ret)
> + goto out_err;
> +
> ret = bdev->funcs->move(bo, evict, ctx, mem, hop);
> if (ret) {
> if (ret == -EMULTIHOP)
> @@ -735,7 +739,7 @@ static int ttm_bo_add_move_fence(struct ttm_buffer_object
> *bo,
>
> dma_resv_add_shared_fence(bo->base.resv, fence);
>
> - ret = dma_resv_reserve_shared(bo->base.resv, 1);
> + ret = dma_resv_reserve_fences(bo->base.resv, 1);
> if (unlikely(ret)) {
> dma_fence_put(fence);
> return ret;
> @@ -794,7 +798,7 @@ int ttm_bo_mem_space(struct ttm_buffer_object *bo,
> bool type_found = false;
> int i, ret;
>
> - ret = dma_resv_reserve_shared(bo->base.resv, 1);
> + ret = dma_resv_reserve_fences(bo->base.resv, 1);
> if (unlikely(ret))
> return ret;
>
> diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c
> b/drivers/gpu/drm/ttm/ttm_bo_util.c
> index 219dd81bbeab..1b96b91bf81b 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo_util.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
> @@ -221,9 +221,6 @@ static int ttm_buffer_object_transfer(struct
> ttm_buffer_object *bo,
>
> fbo->base = *bo;
>
> - ttm_bo_get(bo);
> - fbo->bo = bo;
> -
> /**
> * Fix up members that we shouldn't copy directly:
> * TODO: Explicit member copy would probably be better here.
> @@ -250,6 +247,15 @@ static int ttm_buffer_object_transfer(struct
> ttm_buffer_object *bo,
> ret = dma_resv_trylock(&fbo->base.base._resv);
> WARN_ON(!ret);
>
> + ret = dma_resv_reserve_fences(&fbo->base.base._resv, 1);
> + if (ret) {
> + kfree(fbo);
> + return ret;
> + }
> +
> + ttm_bo_get(bo);
> + fbo->bo = bo;
> +
> ttm_bo_move_to_lru_tail_unlocked(&fbo->base);
>
> *new_obj = &fbo->base;
> diff --git a/drivers/gpu/drm/ttm/ttm_execbuf_util.c
> b/drivers/gpu/drm/ttm/ttm_execbuf_util.c
> index 071c48d672c6..789c645f004e 100644
> --- a/drivers/gpu/drm/ttm/ttm_execbuf_util.c
> +++ b/drivers/gpu/drm/ttm/ttm_execbuf_util.c
> @@ -90,6 +90,7 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
>
> list_for_each_entry(entry, list, head) {
> struct ttm_buffer_object *bo = entry->bo;
> + unsigned int num_fences;
>
> ret = ttm_bo_reserve(bo, intr, (ticket == NULL), ticket);
> if (ret == -EALREADY && dups) {
> @@ -100,12 +101,10 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx
> *ticket,
> continue;
> }
>
> + num_fences = min(entry->num_shared, 1u);
> if (!ret) {
> - if (!entry->num_shared)
> - continue;
> -
> - ret = dma_resv_reserve_shared(bo->base.resv,
> -
> entry->num_shared);
> + ret = dma_resv_reserve_fences(bo->base.resv,
> + num_fences);
> if (!ret)
> continue;
> }
> @@ -120,9 +119,9 @@ int ttm_eu_reserve_buffers(struct ww_acquire_ctx *ticket,
> ret = ttm_bo_reserve_slowpath(bo, intr, ticket);
> }
>
> - if (!ret && entry->num_shared)
> - ret = dma_resv_reserve_shared(bo->base.resv,
> -
> entry->num_shared);
> + if (!ret)
> + ret = dma_resv_reserve_fences(bo->base.resv,
> + num_fences);
>
> if (unlikely(ret != 0)) {
> if (ticket) {
> diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c
> index 92bc0faee84f..961812d33827 100644
> --- a/drivers/gpu/drm/v3d/v3d_gem.c
> +++ b/drivers/gpu/drm/v3d/v3d_gem.c
> @@ -259,16 +259,21 @@ v3d_lock_bo_reservations(struct v3d_job *job,
> return ret;
>
> for (i = 0; i < job->bo_count; i++) {
> + ret = dma_resv_reserve_fences(job->bo[i]->resv, 1);
> + if (ret)
> + goto fail;
> +
> ret = drm_sched_job_add_implicit_dependencies(&job->base,
> job->bo[i], true);
> - if (ret) {
> - drm_gem_unlock_reservations(job->bo, job->bo_count,
> - acquire_ctx);
> - return ret;
> - }
> + if (ret)
> + goto fail;
> }
>
> return 0;
> +
> +fail:
> + drm_gem_unlock_reservations(job->bo, job->bo_count, acquire_ctx);
> + return ret;
> }
>
> /**
> diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c
> index 4abf10b66fe8..594bd6bb00d2 100644
> --- a/drivers/gpu/drm/vc4/vc4_gem.c
> +++ b/drivers/gpu/drm/vc4/vc4_gem.c
> @@ -644,7 +644,7 @@ vc4_lock_bo_reservations(struct drm_device *dev,
> for (i = 0; i < exec->bo_count; i++) {
> bo = &exec->bo[i]->base;
>
> - ret = dma_resv_reserve_shared(bo->resv, 1);
> + ret = dma_resv_reserve_fences(bo->resv, 1);
> if (ret) {
> vc4_unlock_bo_reservations(dev, exec, acquire_ctx);
> return ret;
> diff --git a/drivers/gpu/drm/vgem/vgem_fence.c
> b/drivers/gpu/drm/vgem/vgem_fence.c
> index bd6f75285fd9..2ddbebca87d9 100644
> --- a/drivers/gpu/drm/vgem/vgem_fence.c
> +++ b/drivers/gpu/drm/vgem/vgem_fence.c
> @@ -157,12 +157,14 @@ int vgem_fence_attach_ioctl(struct drm_device *dev,
> }
>
> /* Expose the fence via the dma-buf */
> - ret = 0;
> dma_resv_lock(resv, NULL);
> - if (arg->flags & VGEM_FENCE_WRITE)
> - dma_resv_add_excl_fence(resv, fence);
> - else if ((ret = dma_resv_reserve_shared(resv, 1)) == 0)
> - dma_resv_add_shared_fence(resv, fence);
> + ret = dma_resv_reserve_fences(resv, 1);
> + if (!ret) {
> + if (arg->flags & VGEM_FENCE_WRITE)
> + dma_resv_add_excl_fence(resv, fence);
> + else
> + dma_resv_add_shared_fence(resv, fence);
> + }
> dma_resv_unlock(resv);
>
> /* Record the fence in our idr for later signaling */
> diff --git a/drivers/gpu/drm/virtio/virtgpu_gem.c
> b/drivers/gpu/drm/virtio/virtgpu_gem.c
> index 48d3c9955f0d..1820ca6cf673 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_gem.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_gem.c
> @@ -214,6 +214,7 @@ void virtio_gpu_array_add_obj(struct
> virtio_gpu_object_array *objs,
>
> int virtio_gpu_array_lock_resv(struct virtio_gpu_object_array *objs)
> {
> + unsigned int i;
> int ret;
>
> if (objs->nents == 1) {
> @@ -222,6 +223,14 @@ int virtio_gpu_array_lock_resv(struct
> virtio_gpu_object_array *objs)
> ret = drm_gem_lock_reservations(objs->objs, objs->nents,
> &objs->ticket);
> }
> + if (ret)
> + return ret;
> +
> + for (i = 0; i < objs->nents; ++i) {
> + ret = dma_resv_reserve_fences(objs->objs[i]->resv, 1);
> + if (ret)
> + return ret;
> + }
> return ret;
> }
>
> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_bo.c
> b/drivers/gpu/drm/vmwgfx/vmwgfx_bo.c
> index 31aecc46624b..fe13aa8b4a64 100644
> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_bo.c
> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_bo.c
> @@ -747,16 +747,22 @@ void vmw_bo_fence_single(struct ttm_buffer_object *bo,
> struct vmw_fence_obj *fence)
> {
> struct ttm_device *bdev = bo->bdev;
> -
> struct vmw_private *dev_priv =
> container_of(bdev, struct vmw_private, bdev);
> + int ret;
>
> - if (fence == NULL) {
> + if (fence == NULL)
> vmw_execbuf_fence_commands(NULL, dev_priv, &fence, NULL);
> + else
> + dma_fence_get(&fence->base);
> +
> + ret = dma_resv_reserve_fences(bo->base.resv, 1);
> + if (!ret)
> dma_resv_add_excl_fence(bo->base.resv, &fence->base);
> - dma_fence_put(&fence->base);
> - } else
> - dma_resv_add_excl_fence(bo->base.resv, &fence->base);
> + else
> + /* Last resort fallback when we are OOM */
> + dma_fence_wait(&fence->base, false);
> + dma_fence_put(&fence->base);
> }
>
>
> diff --git a/include/linux/dma-resv.h b/include/linux/dma-resv.h
> index ecb697d4d861..5fa04d0fccad 100644
> --- a/include/linux/dma-resv.h
> +++ b/include/linux/dma-resv.h
> @@ -117,7 +117,7 @@ struct dma_resv {
> * A new fence is added by calling dma_resv_add_shared_fence(). Since
> * this often needs to be done past the point of no return in command
> * submission it cannot fail, and therefore sufficient slots need to be
> - * reserved by calling dma_resv_reserve_shared().
> + * reserved by calling dma_resv_reserve_fences().
> *
> * Note that actual semantics of what an exclusive or shared fence mean
> * is defined by the user, for reservation objects shared across drivers
> @@ -413,7 +413,7 @@ static inline void dma_resv_unlock(struct dma_resv *obj)
>
> void dma_resv_init(struct dma_resv *obj);
> void dma_resv_fini(struct dma_resv *obj);
> -int dma_resv_reserve_shared(struct dma_resv *obj, unsigned int num_fences);
> +int dma_resv_reserve_fences(struct dma_resv *obj, unsigned int num_fences);
> void dma_resv_add_shared_fence(struct dma_resv *obj, struct dma_fence
> *fence);
> void dma_resv_replace_fences(struct dma_resv *obj, uint64_t context,
> struct dma_fence *fence);
> --
> 2.25.1
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
