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ROCm
question about cache line size
No. There is no cache line query on HIP side.
If you are curious about cache line size on your GPU, you can use CL_DEVICE_GLOBAL_MEM_CACHELINE_SIZE on OpenCL.
Will a HIP API be added for that ? In general, will APIs be added for other properties that are only available in OpenCL ? Thanks.
Are there some general rules about the size ? Is the size based on discrete or integrated, consumer or data center, etc ? Most people couldn't buy all AMD GPU products.
HIP does have a cache-line query. Can you please explain what are you trying to do with cache size, maybe we can find a way to work around it.
There is a cache-line size query in SYCL. Then the query can be supported in the HIP backend of the SYCL. Thank you.
HIP will not add the query.
Although there are ways to get this information from other parts of ROCm stack. For example if you are on linux and HSA you can use the cacheline query:
#include <hsa/hsa.h>
#include <hsa/hsa_ext_amd.h>
#include <iostream>
#include <vector>
#define check(hsa_call) \
{ \
auto res = hsa_call; \
if (res != HSA_STATUS_SUCCESS) { \
std::cout << "failed in hsa call: " << #hsa_call << std::endl; \
std::abort(); \
} \
}
hsa_status_t agent_callback(hsa_agent_t agent, void *data) {
hsa_device_type_t dev_type = HSA_DEVICE_TYPE_CPU;
auto agents = reinterpret_cast<std::vector<hsa_agent_t> *>(data);
hsa_status_t stat =
hsa_agent_get_info(agent, HSA_AGENT_INFO_DEVICE, &dev_type);
if (dev_type == HSA_DEVICE_TYPE_GPU) {
agents->push_back(agent);
}
return stat;
}
std::vector<hsa_agent_t> get_hsa_agents() {
std::vector<hsa_agent_t> agents;
check(hsa_iterate_agents(agent_callback, (void *)(&agents)));
return agents;
}
std::string get_agent_name(hsa_agent_t agent) {
std::string name(64, 0);
check(hsa_agent_get_info(
agent, static_cast<hsa_agent_info_t>(HSA_AMD_AGENT_INFO_PRODUCT_NAME),
name.data()));
return name;
}
unsigned int get_agent_cache_line_size(hsa_agent_t agent) {
unsigned int csize = 0;
check(hsa_agent_get_info(
agent, static_cast<hsa_agent_info_t>(HSA_AMD_AGENT_INFO_CACHELINE_SIZE),
&csize));
return csize;
}
int main() {
check(hsa_init());
auto agents = get_hsa_agents();
if (agents.size() == 0) {
std::cerr << "No gpus found..." << std::endl;
std::abort();
}
for (auto &agent : agents) {
auto name = get_agent_name(agent);
auto cache_line_size = get_agent_cache_line_size(agent);
std::cout << "Agent: " << name
<< " has cache line size of: " << cache_line_size << std::endl;
}
check(hsa_shut_down());
}
To compile: g++ file.cpp -I /opt/rocm/include -L /opt/rocm/lib -lhsa-runtime64 -o out