Revert "Vulkan: Enforce fixed subgroup size for compute shaders."

This reverts commit 56f1678437.

Reason for revert: crbug.com/1059205
Bug: chromium:1059205

Original change's description:
> Vulkan: Enforce fixed subgroup size for compute shaders.
>
> This CL ensures that, on architectures with a varying subgroup size,
> compute shaders are always compiled with a fixed subgroup size to
> avoid consistency issues when one shader writes data in a subgroup-size
> dependent layout to GPU memory, to be read by another shader in a
> future dispatch.
>
> At the moment, only Intel ICDs are known to implement this [1],
> and the code uses a heuristics to chose the size of 16, which seems to
> be the sweet spot according to Intel engineers.
>
> + Update the PNextChainBuilder class to deal with the fact that
>   VkComputePipelineCreateInfo::pNext is defined as a const void*,
>   which created compiler errors in the previous implementation.
>
> [1] https://bugs.freedesktop.org/show_bug.cgi?id=108875
>
> Change-Id: I332faa53b9f854a8abe43a7271f30d8c5deb2142
> Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/16021
> Commit-Queue: Corentin Wallez <cwallez@chromium.org>
> Reviewed-by: Corentin Wallez <cwallez@chromium.org>

TBR=cwallez@google.com,cwallez@chromium.org,enga@chromium.org,enga@google.com,david.turner.dev@gmail.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I922eccc310505da4b4a9fc853335733ca4900fc8
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/16521
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
This commit is contained in:
Corentin Wallez 2020-03-06 13:03:00 +00:00 committed by Commit Bot service account
parent ddc5cacc27
commit 36f0388f79
3 changed files with 0 additions and 50 deletions

View File

@ -18,7 +18,6 @@
#include "dawn_native/vulkan/FencedDeleter.h"
#include "dawn_native/vulkan/PipelineLayoutVk.h"
#include "dawn_native/vulkan/ShaderModuleVk.h"
#include "dawn_native/vulkan/UtilsVulkan.h"
#include "dawn_native/vulkan/VulkanError.h"
namespace dawn_native { namespace vulkan {
@ -51,18 +50,6 @@ namespace dawn_native { namespace vulkan {
createInfo.stage.pSpecializationInfo = nullptr;
Device* device = ToBackend(GetDevice());
PNextChainBuilder extChain(&createInfo);
VkPipelineShaderStageRequiredSubgroupSizeCreateInfoEXT subgroupSizeInfo = {};
uint32_t computeSubgroupSize = device->GetComputeSubgroupSize();
if (computeSubgroupSize != 0u) {
extChain.Add(
&subgroupSizeInfo,
VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_REQUIRED_SUBGROUP_SIZE_CREATE_INFO_EXT);
subgroupSizeInfo.requiredSubgroupSize = computeSubgroupSize;
}
return CheckVkSuccess(
device->fn.CreateComputePipelines(device->GetVkDevice(), ::VK_NULL_HANDLE, 1,
&createInfo, nullptr, &*mHandle),

View File

@ -388,8 +388,6 @@ namespace dawn_native { namespace vulkan {
*dst = mDeviceInfo.featuresExtensions.subgroupSizeControl;
featuresChain.Add(dst);
mComputeSubgroupSize = FindComputeSubgroupSize();
}
// Always require independentBlend because it is a core Dawn feature
@ -466,33 +464,6 @@ namespace dawn_native { namespace vulkan {
return usedKnobs;
}
uint32_t Device::FindComputeSubgroupSize() const {
if (!mDeviceInfo.subgroupSizeControl) {
return 0;
}
const VkPhysicalDeviceSubgroupSizeControlPropertiesEXT& ext =
mDeviceInfo.propertiesExtensions.subgroupSizeControl;
if (ext.minSubgroupSize == ext.maxSubgroupSize) {
return 0;
}
// At the moment, only Intel devices support varying subgroup sizes
// and 16, which is the next value after the minimum of 8, is the sweet
// spot according to [1]. Hence the following heuristics, which may
// need to be adjusted in the future for other architectures, or if
// a specific API is added to let client code select the size..
//
// [1] https://bugs.freedesktop.org/show_bug.cgi?id=108875
uint32_t subgroupSize = ext.minSubgroupSize * 2;
if (subgroupSize <= ext.maxSubgroupSize) {
return subgroupSize;
} else {
return ext.minSubgroupSize;
}
}
void Device::GatherQueueFromDevice() {
fn.GetDeviceQueue(mVkDevice, mQueueFamily, 0, &mQueue);
}

View File

@ -100,12 +100,6 @@ namespace dawn_native { namespace vulkan {
ResourceMemoryAllocator* GetResourceMemoryAllocatorForTesting() const;
// Return the fixed subgroup size to use for compute shaders on this device,
// or 0 if none needs to be set.
uint32_t GetComputeSubgroupSize() const {
return mComputeSubgroupSize;
}
private:
ResultOrError<BindGroupBase*> CreateBindGroupImpl(
const BindGroupDescriptor* descriptor) override;
@ -136,7 +130,6 @@ namespace dawn_native { namespace vulkan {
ResultOrError<VulkanDeviceKnobs> CreateDevice(VkPhysicalDevice physicalDevice);
void GatherQueueFromDevice();
uint32_t FindComputeSubgroupSize() const;
void InitTogglesFromDriver();
void ApplyDepth24PlusS8Toggle();
@ -151,7 +144,6 @@ namespace dawn_native { namespace vulkan {
VkDevice mVkDevice = VK_NULL_HANDLE;
uint32_t mQueueFamily = 0;
VkQueue mQueue = VK_NULL_HANDLE;
uint32_t mComputeSubgroupSize = 0;
std::unique_ptr<DescriptorSetService> mDescriptorSetService;
std::unique_ptr<FencedDeleter> mDeleter;