From 0e1d8083bddb38b7169f6240905422f95d3c31b9 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Christian=20K=C3=B6nig?= Date: Mon, 5 Aug 2019 11:16:12 +0200 Subject: [PATCH] dma-buf: further relax reservation_object_add_shared_fence MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Other cores don't busy wait any more and we removed the last user of checking the seqno for changes. Drop updating the number for shared fences altogether. Signed-off-by: Christian König Reviewed-by: Chris Wilson Link: https://patchwork.freedesktop.org/patch/322379/?series=64837&rev=1 --- drivers/dma-buf/reservation.c | 6 ------ drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 7 +------ 2 files changed, 1 insertion(+), 12 deletions(-) diff --git a/drivers/dma-buf/reservation.c b/drivers/dma-buf/reservation.c index 8fcaddffd5d4..90bc6ef03598 100644 --- a/drivers/dma-buf/reservation.c +++ b/drivers/dma-buf/reservation.c @@ -237,9 +237,6 @@ void reservation_object_add_shared_fence(struct reservation_object *obj, fobj = reservation_object_get_list(obj); count = fobj->shared_count; - preempt_disable(); - write_seqcount_begin(&obj->seq); - for (i = 0; i < count; ++i) { old = rcu_dereference_protected(fobj->shared[i], @@ -257,9 +254,6 @@ replace: RCU_INIT_POINTER(fobj->shared[i], fence); /* pointer update must be visible before we extend the shared_count */ smp_store_mb(fobj->shared_count, count); - - write_seqcount_end(&obj->seq); - preempt_enable(); dma_fence_put(old); } EXPORT_SYMBOL(reservation_object_add_shared_fence); diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c index fe062b76ec91..a4640ddc24d1 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c @@ -251,12 +251,7 @@ static int amdgpu_amdkfd_remove_eviction_fence(struct amdgpu_bo *bo, new->shared_max = old->shared_max; new->shared_count = k; - /* Install the new fence list, seqcount provides the barriers */ - preempt_disable(); - write_seqcount_begin(&resv->seq); - RCU_INIT_POINTER(resv->fence, new); - write_seqcount_end(&resv->seq); - preempt_enable(); + rcu_assign_pointer(resv->fence, new); /* Drop the references to the removed fences or move them to ef_list */ for (i = j, k = 0; i < old->shared_count; ++i) { -- 2.30.2