diff --git a/mlir/include/mlir/Dialect/GPU/GPUOps.td b/mlir/include/mlir/Dialect/GPU/GPUOps.td --- a/mlir/include/mlir/Dialect/GPU/GPUOps.td +++ b/mlir/include/mlir/Dialect/GPU/GPUOps.td @@ -291,12 +291,14 @@ let parser = [{ return parseGPUFuncOp(parser, result); }]; } -def GPU_LaunchFuncOp : GPU_Op<"launch_func">, - Arguments<(ins SymbolRefAttr:$kernel, +def GPU_LaunchFuncOp : GPU_Op<"launch_func", + [GPU_AsyncOpInterface, AttrSizedOperandSegments]>, + Arguments<(ins Variadic:$asyncDependencies, + SymbolRefAttr:$kernel, Index:$gridSizeX, Index:$gridSizeY, Index:$gridSizeZ, Index:$blockSizeX, Index:$blockSizeY, Index:$blockSizeZ, Variadic:$operands)>, - Results<(outs)> { + Results<(outs Optional:$asyncToken)> { let summary = "Launches a function as a GPU kernel"; let description = [{ @@ -308,14 +310,22 @@ function is required to be a gpu.module. And finally, the module containing the kernel module (which thus cannot be the top-level module) is required to have the `gpu.container_module` attribute. The `gpu.launch_func` - operation has a symbol attribute named `kernel` to identify the fully + operation has a symbol attribute named `kernel` to identify the fully specified kernel function to launch (both the gpu.module and func). - The operation takes at least six operands, with the first three operands - being grid sizes along x,y,z dimensions and the following three being block - sizes along x,y,z dimensions. When a lower-dimensional kernel is required, - unused sizes must be explicitly set to `1`. The remaining operands are - passed as arguments to the kernel function. + The `gpu.launch_func` supports async dependencies: the kernel does not start + executing until the ops producing those async dependencies have completed. + + By the default, the host implicitly blocks until kernel execution has + completed. If the `async` keyword is present, the host does not block but + instead a `!gpu.async.token` is returned. Other async GPU ops can take this + token as dependency. + + The operation requires at least the grid and block sizes along the x,y,z + dimensions as arguments. When a lower-dimensional kernel is required, + unused sizes must be explicitly set to `1`. + + The remaining operands are passed as arguments to the kernel function. Example: @@ -351,11 +361,15 @@ } } + %t0 = gpu.wait async gpu.launch_func - @kernels::@kernel_1 // Kernel function. - blocks in (%cst, %cst, %cst) // Grid size. - threads in (%cst, %cst, %cst) // Block size. - args(%arg0 : f32, %arg1 : memref) // Kernel arguments. + async // (Optional) Don't block host, return token. + [%t0] // (Optional) Execute only after %t0 has completed. + @kernels::@kernel_1 // Kernel function. + blocks in (%cst, %cst, %cst) // Grid size. + threads in (%cst, %cst, %cst) // Block size. + args(%arg0 : f32, // (Optional) Kernel arguments. + %arg1 : memref) } ``` }]; @@ -401,6 +415,7 @@ let verifier = [{ return ::verify(*this); }]; let assemblyFormat = [{ + custom(type($asyncToken), $asyncDependencies) $kernel `blocks` `in` ` ` `(`$gridSizeX`,` $gridSizeY`,` $gridSizeZ`)` `threads` `in` ` ` `(`$blockSizeX`,` $blockSizeY`,` $blockSizeZ`)` diff --git a/mlir/lib/Dialect/GPU/IR/GPUDialect.cpp b/mlir/lib/Dialect/GPU/IR/GPUDialect.cpp --- a/mlir/lib/Dialect/GPU/IR/GPUDialect.cpp +++ b/mlir/lib/Dialect/GPU/IR/GPUDialect.cpp @@ -438,10 +438,15 @@ auto kernelSymbol = builder.getSymbolRefAttr( kernelModule.getName(), {builder.getSymbolRefAttr(kernelFunc.getName())}); result.addAttribute(getKernelAttrName(), kernelSymbol); + SmallVector segmentSizes(8, 1); + segmentSizes.front() = 0; // Initially no async dependencies. + segmentSizes.back() = static_cast(kernelOperands.size()); + result.addAttribute(getOperandSegmentSizeAttr(), + builder.getI32VectorAttr(segmentSizes)); } unsigned LaunchFuncOp::getNumKernelOperands() { - return getNumOperands() - kNumConfigOperands; + return getNumOperands() - asyncDependencies().size() - kNumConfigOperands; } StringRef LaunchFuncOp::getKernelModuleName() { @@ -451,15 +456,17 @@ StringRef LaunchFuncOp::getKernelName() { return kernel().getLeafReference(); } Value LaunchFuncOp::getKernelOperand(unsigned i) { - return getOperation()->getOperand(i + kNumConfigOperands); + return getOperand(asyncDependencies().size() + kNumConfigOperands + i); } KernelDim3 LaunchFuncOp::getGridSizeOperandValues() { - return KernelDim3{getOperand(0), getOperand(1), getOperand(2)}; + auto operands = getOperands().drop_front(asyncDependencies().size()); + return KernelDim3{operands[0], operands[1], operands[2]}; } KernelDim3 LaunchFuncOp::getBlockSizeOperandValues() { - return KernelDim3{getOperand(3), getOperand(4), getOperand(5)}; + auto operands = getOperands().drop_front(asyncDependencies().size()); + return KernelDim3{operands[3], operands[4], operands[5]}; } static LogicalResult verify(LaunchFuncOp op) { diff --git a/mlir/test/Dialect/GPU/invalid.mlir b/mlir/test/Dialect/GPU/invalid.mlir --- a/mlir/test/Dialect/GPU/invalid.mlir +++ b/mlir/test/Dialect/GPU/invalid.mlir @@ -37,6 +37,7 @@ func @launch_func_too_few_operands(%sz : index) { // expected-error@+1 {{expected 6 or more operands}} "gpu.launch_func"(%sz, %sz, %sz, %sz, %sz) + {operand_segment_sizes = dense<[0, 1, 1, 1, 1, 1, 0, 0]> : vector<8xi32>} : (index, index, index, index, index) -> () return } @@ -55,6 +56,7 @@ func @launch_func_missing_callee_attribute(%sz : index) { // expected-error@+1 {{'gpu.launch_func' op requires attribute 'kernel'}} "gpu.launch_func"(%sz, %sz, %sz, %sz, %sz, %sz) + {operand_segment_sizes = dense<[0, 1, 1, 1, 1, 1, 1, 0]> : vector<8xi32>} : (index, index, index, index, index, index) -> () return } diff --git a/mlir/test/Dialect/GPU/ops.mlir b/mlir/test/Dialect/GPU/ops.mlir --- a/mlir/test/Dialect/GPU/ops.mlir +++ b/mlir/test/Dialect/GPU/ops.mlir @@ -73,6 +73,7 @@ %1 = "op"() : () -> (memref) // CHECK: %{{.*}} = constant 8 %cst = constant 8 : index + %t0 = gpu.wait async // CHECK: gpu.launch_func @kernels::@kernel_1 blocks in (%{{.*}}, %{{.*}}, %{{.*}}) threads in (%{{.*}}, %{{.*}}, %{{.*}}) args(%{{.*}} : f32, %{{.*}} : memref) gpu.launch_func @kernels::@kernel_1 blocks in (%cst, %cst, %cst) threads in (%cst, %cst, %cst) args(%0 : f32, %1 : memref) @@ -80,6 +81,9 @@ // CHECK: gpu.launch_func @kernels::@kernel_2 blocks in (%{{.*}}, %{{.*}}, %{{.*}}) threads in (%{{.*}}, %{{.*}}, %{{.*}}) gpu.launch_func @kernels::@kernel_2 blocks in (%cst, %cst, %cst) threads in (%cst, %cst, %cst) + // CHECK: %{{.*}} = gpu.launch_func async [%{{.*}}] @kernels::@kernel_2 blocks in (%{{.*}}, %{{.*}}, %{{.*}}) threads in (%{{.*}}, %{{.*}}, %{{.*}}) + %t1 = gpu.launch_func async [%t0] @kernels::@kernel_2 blocks in (%cst, %cst, %cst) threads in (%cst, %cst, %cst) + return }