gs_nvshmem.cu

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/*
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#include <device/device_config.h>
#include <device/cuda/check.h>
#ifdef HAVE_NVSHMEM
#include <nvshmem.h>
#include "gs_kernels.h"
#include "gs_nvshmem_kernels.h"
#endif
 
extern "C" {
 
#ifdef HAVE_NVSHMEM
  void cudamalloc_nvshmem(void** ptr, size_t size)
  {
    *ptr = nvshmem_malloc(size);
    CUDA_CHECK(cudaGetLastError());
    cudaMemset(*ptr, 0, size);
    CUDA_CHECK(cudaGetLastError());
  }
 
  void cudafree_nvshmem(void** ptr, size_t size)
  {
    nvshmem_free(*ptr);
    CUDA_CHECK(cudaGetLastError());
  }
 
  void cuda_gs_nvshmem_pack(void *u_d, void *buf_d, void *dof_d,
                            int boffset, int n, cudaStream_t stream)
  {
    if (n == 0) return;
 
    const int nthrds = 1024;
    const int nblcks = (n + nthrds - 1) / nthrds;
 
    gs_pack_kernel<real>
      <<<nblcks, nthrds, 0, stream>>>((real *) u_d, (real *) buf_d + boffset,
                                      (int *) dof_d, n);
    CUDA_CHECK(cudaGetLastError());
  }
 
  void cuda_gs_nvshmem_pack_vec(void *u_d, void *buf_d, void *dof_d,
                                int boffset, int n, int nc, int ns,
                                cudaStream_t stream)
  {
    if (n == 0) return;
 
    const int nthrds = 1024;
    const int nblcks = (n + nthrds - 1) / nthrds;
 
    gs_pack_vec_kernel<real>
      <<<nblcks, nthrds, 0, stream>>>((real *) u_d, (real *) buf_d + boffset,
                                      (int *) dof_d, n, nc, ns);
    CUDA_CHECK(cudaGetLastError());
  }
 
  void cuda_gs_push(void *sbuf_d, int soffset, int n, cudaStream_t stream,
                    int destRank, void *rbuf_d, int roffset, int iter,
                    void *done_d, void *ready_d, int mype)
  {
    const int nthrds = 1024;
 
    pushShmemKernel<real>
      <<<1,nthrds,0,stream>>>((real *) rbuf_d + roffset,
                              (real *) sbuf_d + soffset,
                              (size_t) n, destRank, (uint64_t) iter,
                              (uint64_t *) done_d + mype,
                              (uint64_t *) ready_d + destRank);
    CUDA_CHECK(cudaGetLastError());
  }
 
  void cuda_gs_push_wait(cudaStream_t stream, int iter,
                         void *done_d, int srcRank)
  {
    pushShmemKernelWait<<<1,1,0,stream>>>((uint64_t) iter,
                                          (uint64_t *) done_d + srcRank);
    CUDA_CHECK(cudaGetLastError());
  }
 
  void cuda_gs_post_ready(cudaStream_t stream, int iter, void *ready_d,
                          int mype, int srcRank)
  {
    postReadyShmemKernel<<<1,1,0,stream>>>((uint64_t *) ready_d + mype,
                                           (uint64_t) iter, srcRank);
    CUDA_CHECK(cudaGetLastError());
  }
#endif
}