/*
    Code for tracing mistakes in MPI usage. For example, sends that are never received,
  nonblocking messages that are not correctly waited for, etc.
*/

#include <petscsys.h> /*I "petscsys.h" I*/

#if defined(PETSC_USE_LOG) && !defined(PETSC_HAVE_MPIUNI)

/*@C
   PetscMPIDump - Dumps a listing of incomplete MPI operations, such as sends that
   have never been received, etc.

   Collective on `PETSC_COMM_WORLD`

   Input Parameter:
.  fp - file pointer.  If fp is NULL, stdout is assumed.

   Options Database Key:
.  -mpidump - Dumps MPI incompleteness during call to PetscFinalize()

    Level: developer

.seealso: `PetscMallocDump()`
 @*/
PetscErrorCode PetscMPIDump(FILE *fd)
{
  PetscMPIInt rank;
  double      tsends, trecvs, work;
  int         err;

  PetscFunctionBegin;
  PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
  if (!fd) fd = PETSC_STDOUT;

  /* Did we wait on all the non-blocking sends and receives? */
  PetscCall(PetscSequentialPhaseBegin(PETSC_COMM_WORLD, 1));
  if (petsc_irecv_ct + petsc_isend_ct != petsc_sum_of_waits_ct) {
    PetscCall(PetscFPrintf(PETSC_COMM_SELF, fd, "[%d]You have not waited on all non-blocking sends and receives", rank));
    PetscCall(PetscFPrintf(PETSC_COMM_SELF, fd, "[%d]Number non-blocking sends %g receives %g number of waits %g\n", rank, petsc_isend_ct, petsc_irecv_ct, petsc_sum_of_waits_ct));
    err = fflush(fd);
    PetscCheck(!err, PETSC_COMM_SELF, PETSC_ERR_SYS, "fflush() failed on file");
  }
  PetscCall(PetscSequentialPhaseEnd(PETSC_COMM_WORLD, 1));
  /* Did we receive all the messages that we sent? */
  work = petsc_irecv_ct + petsc_recv_ct;
  PetscCallMPI(MPI_Reduce(&work, &trecvs, 1, MPI_DOUBLE, MPI_SUM, 0, PETSC_COMM_WORLD));
  work = petsc_isend_ct + petsc_send_ct;
  PetscCallMPI(MPI_Reduce(&work, &tsends, 1, MPI_DOUBLE, MPI_SUM, 0, PETSC_COMM_WORLD));
  if (rank == 0 && tsends != trecvs) {
    PetscCall(PetscFPrintf(PETSC_COMM_SELF, fd, "Total number sends %g not equal receives %g\n", tsends, trecvs));
    err = fflush(fd);
    PetscCheck(!err, PETSC_COMM_SELF, PETSC_ERR_SYS, "fflush() failed on file");
  }
  PetscFunctionReturn(0);
}

#else

PetscErrorCode PetscMPIDump(FILE *fd)
{
  PetscFunctionBegin;
  PetscFunctionReturn(0);
}

#endif

#if defined(PETSC_HAVE_MPI_PROCESS_SHARED_MEMORY)
/*
    OpenMPI version of MPI_Win_allocate_shared() does not provide __float128 alignment so we provide
    a utility that insures alignment up to data item size.
*/
PetscErrorCode MPIU_Win_allocate_shared(MPI_Aint sz, PetscMPIInt szind, MPI_Info info, MPI_Comm comm, void *ptr, MPI_Win *win)
{
  float *tmp;

  PetscFunctionBegin;
  PetscCallMPI(MPI_Win_allocate_shared(16 + sz, szind, info, comm, &tmp, win));
  tmp += ((size_t)tmp) % szind ? szind / 4 - ((((size_t)tmp) % szind) / 4) : 0;
  *(void **)ptr = (void *)tmp;
  PetscFunctionReturn(0);
}

PETSC_EXTERN PetscErrorCode MPIU_Win_shared_query(MPI_Win win, PetscMPIInt rank, MPI_Aint *sz, PetscMPIInt *szind, void *ptr)
{
  float *tmp;

  PetscFunctionBegin;
  PetscCallMPI(MPI_Win_shared_query(win, rank, sz, szind, &tmp));
  PetscCheck(*szind > 0, PETSC_COMM_SELF, PETSC_ERR_LIB, "szkind %d must be positive", *szind);
  tmp += ((size_t)tmp) % *szind ? *szind / 4 - ((((size_t)tmp) % *szind) / 4) : 0;
  *(void **)ptr = (void *)tmp;
  PetscFunctionReturn(0);
}

#endif