I am trying to run the c++ code example from the OpenCL C++ Bindings Doc: Example.
Compilation of the c++ code works fine, but compilation of the kernel gives errors in connection with pipes:
<kernel>:10:71: error: unknown type name 'pipe'
global int *output, int val, write_only pipe int outPipe, queue_t childQueue)
^
<kernel>:10:76: error: expected ')'
global int *output, int val, write_only pipe int outPipe, queue_t childQueue)
^
<kernel>:9:30: note: to match this '('
kernel void vectorAdd(global const Foo* aNum, global const int *inputA, global const int *inputB,
^
<kernel>:10:76: error: parameter name omitted
global int *output, int val, write_only pipe int outPipe, queue_t childQueue)
^
<kernel>:13:11: warning: implicit declaration of function 'write_pipe' is invalid in C99
write_pipe(outPipe, &val);
^
<kernel>:13:22: error: use of undeclared identifier 'outPipe'
write_pipe(outPipe, &val);
^
<kernel>:25:26: error: use of undeclared identifier 'childQueue'
enqueue_kernel(childQueue, CLK_ENQUEUE_FLAGS_WAIT_KERNEL, ndrange,
My Setup:
- NVIDIA GPU
- Debian
- used "sudo apt install opencl-headers ocl-icd-opencl-dev -y" to install ocl stuff
clinfo output:
Number of platforms 1
Platform Name NVIDIA CUDA
Platform Vendor NVIDIA Corporation
Platform Version OpenCL 3.0 CUDA 11.4.264
Platform Profile FULL_PROFILE
Platform Extensions cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_khr_fp64 cl_khr_3d_image_writes cl_khr_byte_addressable_store cl_khr_icd cl_khr_gl_sharing cl_nv_compiler_options cl_nv_device_attribute_query cl_nv_pragma_unroll cl_nv_copy_opts cl_nv_create_buffer cl_khr_int64_base_atomics cl_khr_int64_extended_atomics cl_khr_device_uuid cl_khr_pci_bus_info
Platform Extensions with Version cl_khr_global_int32_base_atomics 0x400000 (1.0.0)
cl_khr_global_int32_extended_atomics 0x400000 (1.0.0)
cl_khr_local_int32_base_atomics 0x400000 (1.0.0)
cl_khr_local_int32_extended_atomics 0x400000 (1.0.0)
cl_khr_fp64 0x400000 (1.0.0)
cl_khr_3d_image_writes 0x400000 (1.0.0)
cl_khr_byte_addressable_store 0x400000 (1.0.0)
cl_khr_icd 0x400000 (1.0.0)
cl_khr_gl_sharing 0x400000 (1.0.0)
cl_nv_compiler_options 0x400000 (1.0.0)
cl_nv_device_attribute_query 0x400000 (1.0.0)
cl_nv_pragma_unroll 0x400000 (1.0.0)
cl_nv_copy_opts 0x400000 (1.0.0)
cl_nv_create_buffer 0x400000 (1.0.0)
cl_khr_int64_base_atomics 0x400000 (1.0.0)
cl_khr_int64_extended_atomics 0x400000 (1.0.0)
cl_khr_device_uuid 0x400000 (1.0.0)
cl_khr_pci_bus_info 0x400000 (1.0.0)
Platform Numeric Version 0xc00000 (3.0.0)
Platform Extensions function suffix NV
Platform Host timer resolution 0ns
Platform Name NVIDIA CUDA
Number of devices 1
Device Name NVIDIA GeForce RTX 3060 Ti
Device Vendor NVIDIA Corporation
Device Vendor ID 0x10de
Device Version OpenCL 3.0 CUDA
Device UUID c6edf95f-d769-661d-a242-e9a192a0dcb1
Driver UUID c6edf95f-d769-661d-a242-e9a192a0dcb1
Valid Device LUID No
Device LUID 6d69-637300000000
Device Node Mask 0
Device Numeric Version 0xc00000 (3.0.0)
Driver Version 470.141.03
Device OpenCL C Version OpenCL C 1.2
Device OpenCL C all versions OpenCL C 0x400000 (1.0.0)
OpenCL C 0x401000 (1.1.0)
OpenCL C 0x402000 (1.2.0)
OpenCL C 0xc00000 (3.0.0)
Device OpenCL C features __opencl_c_fp64 0xc00000 (3.0.0)
__opencl_c_images 0xc00000 (3.0.0)
__opencl_c_int64 0xc00000 (3.0.0)
__opencl_c_3d_image_writes 0xc00000 (3.0.0)
Latest comfornace test passed v2021-02-01-00
Device Type GPU
Device Topology (NV) PCI-E, 0000:02:00.0
Device Profile FULL_PROFILE
Device Available Yes
Compiler Available Yes
Linker Available Yes
Max compute units 38
Max clock frequency 1695MHz
Compute Capability (NV) 8.6
Device Partition (core)
Max number of sub-devices 1
Supported partition types None
Supported affinity domains (n/a)
Max work item dimensions 3
Max work item sizes 1024x1024x64
Max work group size 1024
Preferred work group size multiple (device) 32
Preferred work group size multiple (kernel) 32
Warp size (NV) 32
Max sub-groups per work group 0
Preferred / native vector sizes
char 1 / 1
short 1 / 1
int 1 / 1
long 1 / 1
half 0 / 0 (n/a)
float 1 / 1
double 1 / 1 (cl_khr_fp64)
Half-precision Floating-point support (n/a)
Single-precision Floating-point support (core)
Denormals Yes
Infinity and NANs Yes
Round to nearest Yes
Round to zero Yes
Round to infinity Yes
IEEE754-2008 fused multiply-add Yes
Support is emulated in software No
Correctly-rounded divide and sqrt operations Yes
Double-precision Floating-point support (cl_khr_fp64)
Denormals Yes
Infinity and NANs Yes
Round to nearest Yes
Round to zero Yes
Round to infinity Yes
IEEE754-2008 fused multiply-add Yes
Support is emulated in software No
Address bits 64, Little-Endian
Global memory size 8367570944 (7.793GiB)
Error Correction support No
Max memory allocation 2091892736 (1.948GiB)
Unified memory for Host and Device No
Integrated memory (NV) No
Shared Virtual Memory (SVM) capabilities (core)
Coarse-grained buffer sharing Yes
Fine-grained buffer sharing No
Fine-grained system sharing No
Atomics No
Minimum alignment for any data type 128 bytes
Alignment of base address 4096 bits (512 bytes)
Preferred alignment for atomics
SVM 0 bytes
Global 0 bytes
Local 0 bytes
Atomic memory capabilities relaxed, work-group scope
Atomic fence capabilities relaxed, acquire/release, work-group scope
Max size for global variable 0
Preferred total size of global vars 0
Global Memory cache type Read/Write
Global Memory cache size 1089536 (1.039MiB)
Global Memory cache line size 128 bytes
Image support Yes
Max number of samplers per kernel 32
Max size for 1D images from buffer 268435456 pixels
Max 1D or 2D image array size 2048 images
Max 2D image size 32768x32768 pixels
Max 3D image size 16384x16384x16384 pixels
Max number of read image args 256
Max number of write image args 32
Max number of read/write image args 0
Pipe support No
Max number of pipe args 0
Max active pipe reservations 0
Max pipe packet size 0
Local memory type Local
Local memory size 49152 (48KiB)
Registers per block (NV) 65536
Max number of constant args 9
Max constant buffer size 65536 (64KiB)
Generic address space support No
Max size of kernel argument 4352 (4.25KiB)
Queue properties (on host)
Out-of-order execution Yes
Profiling Yes
Device enqueue capabilities (n/a)
Queue properties (on device)
Out-of-order execution No
Profiling No
Preferred size 0
Max size 0
Max queues on device 0
Max events on device 0
Prefer user sync for interop No
Profiling timer resolution 1000ns
Execution capabilities
Run OpenCL kernels Yes
Run native kernels No
Non-uniform work-groups No
Work-group collective functions No
Sub-group independent forward progress No
Kernel execution timeout (NV) Yes
Concurrent copy and kernel execution (NV) Yes
Number of async copy engines 2
IL version (n/a)
ILs with version <printDeviceInfo:186: get CL_DEVICE_ILS_WITH_VERSION : error -30>
printf() buffer size 1048576 (1024KiB)
Built-in kernels (n/a)
Built-in kernels with version <printDeviceInfo:190: get CL_DEVICE_BUILT_IN_KERNELS_WITH_VERSION : error -30>
Device Extensions cl_khr_global_int32_base_atomics cl_khr_global_int32_extended_atomics cl_khr_local_int32_base_atomics cl_khr_local_int32_extended_atomics cl_khr_fp64 cl_khr_3d_image_writes cl_khr_byte_addressable_store cl_khr_icd cl_khr_gl_sharing cl_nv_compiler_options cl_nv_device_attribute_query cl_nv_pragma_unroll cl_nv_copy_opts cl_nv_create_buffer cl_khr_int64_base_atomics cl_khr_int64_extended_atomics cl_khr_device_uuid cl_khr_pci_bus_info
Device Extensions with Version cl_khr_global_int32_base_atomics 0x400000 (1.0.0)
cl_khr_global_int32_extended_atomics 0x400000 (1.0.0)
cl_khr_local_int32_base_atomics 0x400000 (1.0.0)
cl_khr_local_int32_extended_atomics 0x400000 (1.0.0)
cl_khr_fp64 0x400000 (1.0.0)
cl_khr_3d_image_writes 0x400000 (1.0.0)
cl_khr_byte_addressable_store 0x400000 (1.0.0)
cl_khr_icd 0x400000 (1.0.0)
cl_khr_gl_sharing 0x400000 (1.0.0)
cl_nv_compiler_options 0x400000 (1.0.0)
cl_nv_device_attribute_query 0x400000 (1.0.0)
cl_nv_pragma_unroll 0x400000 (1.0.0)
cl_nv_copy_opts 0x400000 (1.0.0)
cl_nv_create_buffer 0x400000 (1.0.0)
cl_khr_int64_base_atomics 0x400000 (1.0.0)
cl_khr_int64_extended_atomics 0x400000 (1.0.0)
cl_khr_device_uuid 0x400000 (1.0.0)
cl_khr_pci_bus_info 0x400000 (1.0.0)
NULL platform behavior
clGetPlatformInfo(NULL, CL_PLATFORM_NAME, ...) NVIDIA CUDA
clGetDeviceIDs(NULL, CL_DEVICE_TYPE_ALL, ...) Success [NV]
clCreateContext(NULL, ...) [default] Success [NV]
clCreateContextFromType(NULL, CL_DEVICE_TYPE_DEFAULT) No platform
clCreateContextFromType(NULL, CL_DEVICE_TYPE_CPU) No devices found in platform
clCreateContextFromType(NULL, CL_DEVICE_TYPE_GPU) No platform
clCreateContextFromType(NULL, CL_DEVICE_TYPE_ACCELERATOR) No devices found in platform
clCreateContextFromType(NULL, CL_DEVICE_TYPE_CUSTOM) Invalid device type for platform
clCreateContextFromType(NULL, CL_DEVICE_TYPE_ALL) No platform
ICD loader properties
ICD loader Name OpenCL ICD Loader
ICD loader Vendor OCL Icd free software
ICD loader Version 2.2.14
ICD loader Profile OpenCL 3.0
I would be happy if someone could help me. I have already researched extensions and opencl versions but found nothing that fixed my problem.
2
Answers
After further research, I came to the conclusion that NVIDIA OpenCL 3.0 does not support all OpenCL 3.0 features. Apparently it is only an OpenCL 1.2 with some new features. Information about this was hidden in the 465.89 Driver Release Notes at page 4.
Pipes are an OpenCL 2 feature. Nvidia does not implement OpenCL 2, only OpenCL 1.2. You can’t run this code on an Nvidia GPU.
Clarification re/from comments:
Note how your
clinfooutput states:In other words, your kernel code must only use features supported by OpenCL 1.2 and any extensions offered by the runtime and selected in your code.
So although the implementation complies with the OpenCL 3.0 specification – which, confusingly, requires fewer features than OpenCL 2.x – you can’t simply use all OpenCL 2.x features.