From 1bf8f49335661fa330877db7badfa6ed264a1bb7 Mon Sep 17 00:00:00 2001
From: Tim Shen <timshen@google.com>
Date: Tue, 30 Jun 2020 19:04:16 -0700
Subject: [PATCH] [StreamExecutor] Workaround the cuFFT bug in CUDA
 10.1/10.2/11.

See https://github.com/google/jax/issues/2874 for details.

PiperOrigin-RevId: 319143928
Change-Id: I8c4759e90d6e9f6e134e5f2a241cb946d7db99b3
---
 tensorflow/stream_executor/cuda/cuda_fft.cc | 36 +++++++++++++++++++--
 tensorflow/stream_executor/cuda/cuda_fft.h  |  6 +++-
 2 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/tensorflow/stream_executor/cuda/cuda_fft.cc b/tensorflow/stream_executor/cuda/cuda_fft.cc
index 79047d989bb..aab263280b5 100644
--- a/tensorflow/stream_executor/cuda/cuda_fft.cc
+++ b/tensorflow/stream_executor/cuda/cuda_fft.cc
@@ -29,6 +29,7 @@ limitations under the License.
 #include "tensorflow/stream_executor/platform/logging.h"
 #include "tensorflow/stream_executor/platform/port.h"
 #include "tensorflow/stream_executor/plugin_registry.h"
+#include "tensorflow/stream_executor/stream.h"
 #include "tensorflow/stream_executor/stream_executor_internal.h"
 
 namespace stream_executor {
@@ -82,6 +83,7 @@ port::Status CUDAFftPlan::Initialize(
     LOG(FATAL) << "Try to repeatedly initialize.";
   }
   is_initialized_ = true;
+  scratch_allocator_ = scratch_allocator;
   cuda::ScopedActivateExecutorContext sac(parent);
   int elem_count_[3], input_embed_[3], output_embed_[3];
   for (int i = 0; i < rank; ++i) {
@@ -243,6 +245,8 @@ port::Status CUDAFftPlan::Initialize(GpuExecutor *parent, Stream *stream,
 
 port::Status CUDAFftPlan::UpdateScratchAllocator(
     Stream *stream, ScratchAllocator *scratch_allocator) {
+  scratch_allocator_ = scratch_allocator;
+
   if (scratch_size_bytes_ != 0) {
     auto allocated = scratch_allocator->AllocateBytes(scratch_size_bytes_);
     if (!allocated.ok() || (scratch_ = allocated.ValueOrDie()) == nullptr) {
@@ -455,6 +459,9 @@ bool CUDAFft::DoFftInternal(Stream *stream, fft::Plan *plan, FuncT cufftExec,
                             const DeviceMemory<InputT> &input,
                             DeviceMemory<OutputT> *output) {
   CUDAFftPlan *cuda_fft_plan = dynamic_cast<CUDAFftPlan *>(plan);
+
+  DeviceMemory<InputT> input_maybe_copy = input;
+
   if (cuda_fft_plan == nullptr) {
     LOG(ERROR) << "the passed-in plan is not a CUDAFftPlan object.";
     return false;
@@ -464,10 +471,33 @@ bool CUDAFft::DoFftInternal(Stream *stream, fft::Plan *plan, FuncT cufftExec,
     return false;
   }
 
+  // Workaround a cuFFT bug, which mutates the input buffer when it shouldn't.
+  // See b/155276727 and go/nvbugs/2959622.
+  // TODO(b/155276727): refine the bounding condition.
+  if (input.opaque() != output->opaque() && CUDA_VERSION >= 10010 &&
+      CUDA_VERSION <= 11000 &&
+      std::is_same<InputT, std::complex<float>>::value &&
+      std::is_same<OutputT, float>::value && input.size() > 0) {
+    auto *allocator = cuda_fft_plan->GetScratchAllocator();
+    if (allocator) {
+      auto allocated = allocator->AllocateBytes(input.size());
+      if (allocated.ok()) {
+        if (stream->ThenMemcpy(&allocated.ValueOrDie(), input, input.size())
+                .ok()) {
+          input_maybe_copy = DeviceMemory<InputT>(allocated.ValueOrDie());
+        }
+      }
+      // Keep going even the workaround fails, since we don't have a good
+      // bounding box. We don't want to give up on a potentially correct
+      // execution just because the allocation for the incorrect case fails.
+    }
+  }
+
   cuda::ScopedActivateExecutorContext sac(parent_);
-  auto ret = cufftExec(cuda_fft_plan->GetPlan(),
-                       GpuComplex(const_cast<InputT *>(GpuMemory(input))),
-                       GpuComplex(GpuMemoryMutable(output)));
+  auto ret =
+      cufftExec(cuda_fft_plan->GetPlan(),
+                GpuComplex(const_cast<InputT *>(GpuMemory(input_maybe_copy))),
+                GpuComplex(GpuMemoryMutable(output)));
 
   if (ret != CUFFT_SUCCESS) {
     LOG(ERROR) << "failed to run cuFFT routine: " << ret;
diff --git a/tensorflow/stream_executor/cuda/cuda_fft.h b/tensorflow/stream_executor/cuda/cuda_fft.h
index e7b0d66cb13..9cb3fd94245 100644
--- a/tensorflow/stream_executor/cuda/cuda_fft.h
+++ b/tensorflow/stream_executor/cuda/cuda_fft.h
@@ -50,7 +50,8 @@ class CUDAFftPlan : public fft::Plan {
         fft_type_(fft::Type::kInvalid),
         scratch_(nullptr),
         scratch_size_bytes_(0),
-        is_initialized_(false) {}
+        is_initialized_(false),
+        scratch_allocator_(nullptr) {}
   ~CUDAFftPlan() override;
 
   // Get FFT direction in cuFFT based on FFT type.
@@ -79,6 +80,8 @@ class CUDAFftPlan : public fft::Plan {
   port::Status UpdateScratchAllocator(Stream *stream,
                                       ScratchAllocator *scratch_allocator);
 
+  ScratchAllocator* GetScratchAllocator() const { return scratch_allocator_; }
+
  protected:
   bool IsInitialized() const { return is_initialized_; }
 
@@ -89,6 +92,7 @@ class CUDAFftPlan : public fft::Plan {
   DeviceMemory<uint8> scratch_;
   size_t scratch_size_bytes_;
   bool is_initialized_;
+  ScratchAllocator* scratch_allocator_;
 };
 
 // FFT support for CUDA platform via cuFFT library.