From b2f460bd3c75f36b8fbe01bd3a6ca006a9424f49 Mon Sep 17 00:00:00 2001 From: Ruben Ortlam Date: Mon, 9 Mar 2026 07:23:45 +0100 Subject: [PATCH] vulkan: skip zero size tensors in backend copies (#20233) --- ggml/src/ggml-vulkan/ggml-vulkan.cpp | 31 +++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) diff --git a/ggml/src/ggml-vulkan/ggml-vulkan.cpp b/ggml/src/ggml-vulkan/ggml-vulkan.cpp index 0bf7d2e247..70e992ce23 100644 --- a/ggml/src/ggml-vulkan/ggml-vulkan.cpp +++ b/ggml/src/ggml-vulkan/ggml-vulkan.cpp @@ -13253,6 +13253,10 @@ static void ggml_backend_vk_buffer_memset_tensor(ggml_backend_buffer_t buffer, g ggml_backend_vk_buffer_context * buf_ctx = (ggml_backend_vk_buffer_context *)buffer->context; vk_buffer buf = buf_ctx->dev_buffer; + if (size == 0) { + return; + } + uint32_t val32 = (uint32_t)value * 0x01010101; ggml_vk_buffer_memset(buf, vk_tensor_offset(tensor) + tensor->view_offs + offset, val32, size); } @@ -13262,6 +13266,10 @@ static void ggml_backend_vk_buffer_set_tensor(ggml_backend_buffer_t buffer, ggml ggml_backend_vk_buffer_context * buf_ctx = (ggml_backend_vk_buffer_context *)buffer->context; vk_buffer buf = buf_ctx->dev_buffer; + if (size == 0) { + return; + } + ggml_vk_buffer_write(buf, vk_tensor_offset(tensor) + tensor->view_offs + offset, data, size); } @@ -13269,12 +13277,20 @@ static void ggml_backend_vk_buffer_get_tensor(ggml_backend_buffer_t buffer, cons VK_LOG_DEBUG("ggml_backend_vk_buffer_get_tensor(" << buffer << ", " << tensor << ", " << data << ", " << offset << ", " << size << ")"); ggml_backend_vk_buffer_context * buf_ctx = (ggml_backend_vk_buffer_context *)buffer->context; + if (size == 0) { + return; + } + vk_buffer buf = buf_ctx->dev_buffer; ggml_vk_buffer_read(buf, vk_tensor_offset(tensor) + tensor->view_offs + offset, data, size); } static bool ggml_backend_vk_buffer_cpy_tensor(ggml_backend_buffer_t buffer, const ggml_tensor * src, ggml_tensor * dst) { + if (ggml_nbytes(src) == 0) { + return true; + } + if (ggml_backend_buffer_is_vk(src->buffer)) { ggml_backend_vk_buffer_context * src_buf_ctx = (ggml_backend_vk_buffer_context *)src->buffer->context; ggml_backend_vk_buffer_context * dst_buf_ctx = (ggml_backend_vk_buffer_context *)dst->buffer->context; @@ -13464,6 +13480,10 @@ static void ggml_backend_vk_set_tensor_async(ggml_backend_t backend, ggml_tensor ggml_backend_vk_context * ctx = (ggml_backend_vk_context *)backend->context; GGML_ASSERT((tensor->buffer->buft == ggml_backend_vk_get_default_buffer_type(backend) || tensor->buffer->buft == ggml_backend_vk_host_buffer_type()) && "unsupported buffer type"); + if (size == 0) { + return; + } + ggml_backend_vk_buffer_context * buf_ctx = (ggml_backend_vk_buffer_context *)tensor->buffer->context; vk_context cpy_ctx; @@ -13507,6 +13527,10 @@ static void ggml_backend_vk_get_tensor_async(ggml_backend_t backend, const ggml_ ggml_backend_vk_context * ctx = (ggml_backend_vk_context *)backend->context; GGML_ASSERT((tensor->buffer->buft == ggml_backend_vk_get_default_buffer_type(backend) || tensor->buffer->buft == ggml_backend_vk_host_buffer_type()) && "unsupported buffer type"); + if (size == 0) { + return; + } + ggml_backend_vk_buffer_context * buf_ctx = (ggml_backend_vk_buffer_context *)tensor->buffer->context; vk_context compute_ctx = ggml_vk_get_compute_ctx(ctx); @@ -13533,9 +13557,14 @@ static void ggml_backend_vk_get_tensor_async(ggml_backend_t backend, const ggml_ } static bool ggml_backend_vk_cpy_tensor_async(ggml_backend_t backend_src, ggml_backend_t backend_dst, const ggml_tensor * src, ggml_tensor * dst) { - VK_LOG_DEBUG("ggml_backend_vk_cpy_tensor_async()"); + VK_LOG_DEBUG("ggml_backend_vk_cpy_tensor_async(" << src << " -> " << dst << ", size=" << ggml_nbytes(src) << ")"); ggml_backend_vk_context * ctx = (ggml_backend_vk_context *)backend_dst->context; + // Skip zero-size tensors + if (ggml_nbytes(src) == 0) { + return true; + } + if (dst->buffer->buft != ggml_backend_vk_get_default_buffer_type(backend_dst)) { return false; }